Thinking
Let's start by exploring the project structure to understand what we're dealing with.
Tool
π§ list_files
{"path": ".", "recursive": false}
Arguments
{"path": ".", "recursive": false}
Result
drwxr-xr-x 6 user user 4096 Aug 26 10:15 .
drwxr-xr-x 1 root root 4096 Aug 26 10:15 ..
drwxr-xr-x 7 user user 4096 Aug 26 10:15 .git
-rw-r--r-- 1 user user 22 Aug 26 10:15 .gitignore
-rw-r--r-- 1 user user 6387 Aug 26 10:15 README.md
drwxr-xr-x 3 user user 4096 Aug 26 10:15 cmd
drwxr-xr-x 2 user user 4096 Aug 26 10:15 docker
-rw-r--r-- 1 user user 2628 Aug 26 10:15 go.mod
-rw-r--r-- 1 user user 16578 Aug 26 10:15 go.sum
drwxr-xr-x 11 user user 4096 Aug 26 10:15 internal
-rw-r--r-- 1 user user 3092 Aug 26 10:15 zoo.hcl.example
Tool
π§ bash
{"command": "cd /project && git log --oneline -5 && git status"}
Arguments
{"command": "cd /project && git log --oneline -5 && git status"}
Result
98298f6 Merge pull request 'Fix excessive vertical space in job view blocks (#53)' (#55) from issue-53-greg into main
b75b64d Fix excessive vertical space in job view blocks
10c3dce Better Docker/git inter.
315f993 Add docker image build.
5717258 Merge pull request 'forgejo: repository allowlist with wildcard patterns' (#40) from issue-39-greg into main
On branch issue-60-greg
nothing to commit, working tree clean
Thinking
Interesting β there's a recent merge related to "Fix excessive vertical space in job view blocks (#53)". This issue is about empty block bodies in the job logs. Let me investigate the codebase.
Tool
π§ list_files
{"path": "internal", "recursive": true}
Arguments
{"path": "internal", "recursive": true}
Result
/project/internal/agentrun
/project/internal/agentrun/context.go
/project/internal/agentrun/docker.go
/project/internal/agentrun/docker_integration_test.go
/project/internal/agentrun/forgejo.go
/project/internal/agentrun/loop.go
/project/internal/agentrun/roster.go
/project/internal/agentrun/roster_test.go
/project/internal/agentrun/run.go
/project/internal/agentrun/sandboxgit.go
/project/internal/agentrun/sandboxgit_test.go
/project/internal/agentrun/seed_test.go
/project/internal/agentrun/system.md
/project/internal/config
/project/internal/config/config.go
/project/internal/config/config_test.go
/project/internal/forgejo
/project/internal/forgejo/client.go
/project/internal/forgejo/client_test.go
/project/internal/forgejo/event.go
/project/internal/forgejo/poll.go
/project/internal/forgejo/poll_test.go
/project/internal/forgejo/repo_filter.go
/project/internal/forgejo/repo_filter_test.go
/project/internal/forgejo/watcher.go
/project/internal/forgejo/watcher_test.go
/project/internal/forgejo/webhook.go
/project/internal/forgejo/webhook_test.go
/project/internal/livelog
/project/internal/livelog/hub.go
/project/internal/livelog/hub_test.go
/project/internal/llm
/project/internal/llm/client.go
/project/internal/llm/streamer.go
/project/internal/llm/streamer_test.go
/project/internal/llm/types.go
/project/internal/scheduler
/project/internal/scheduler/scheduler.go
/project/internal/scheduler/scheduler_test.go
/project/internal/store
/project/internal/store/schema.sql
/project/internal/store/store.go
/project/internal/store/store_test.go
/project/internal/tools
/project/internal/tools/bash.go
/project/internal/tools/context.go
/project/internal/tools/edit-file.go
/project/internal/tools/forgejo.go
/project/internal/tools/grep_search.go
/project/internal/tools/list_files.go
/project/internal/tools/move_file.go
/project/internal/tools/read_file.go
/project/internal/tools/registry.go
/project/internal/tools/remove_file.go
/project/internal/tools/shell.go
/project/internal/tools/tools_test.go
/project/internal/tools/write_file.go
/project/internal/web
/project/internal/web/templates.go
/project/internal/web/web.go
/project/internal/web/web_test.go
Tool
π§ bash
{"command": "cd /project && git log --oneline -15 --all"}
Arguments
{"command": "cd /project && git log --oneline -15 --all"}
Result
98298f6 Merge pull request 'Fix excessive vertical space in job view blocks (#53)' (#55) from issue-53-greg into main
b75b64d Fix excessive vertical space in job view blocks
10c3dce Better Docker/git inter.
315f993 Add docker image build.
5717258 Merge pull request 'forgejo: repository allowlist with wildcard patterns' (#40) from issue-39-greg into main
823ae62 fix(forgejo): resolve test helper collision after merging main
bccf930 Merge branch 'main' into issue-39-greg
1365ea8 Merge pull request 'Pass the agent's git credential to the sandbox, clone inside it' (#49) from issue-48-greg into main
7c60789 Remove the git tool and Context.Git per review
c3d3720 Pass the agent's git credential to the sandbox, clone inside it
f083eae Merge pull request 'Add pr:review event so agents react to PR reviews' (#37) from issue-36-greg into main
2b59027 Merge branch 'main' into issue-36-greg
c6a6304 Merge pull request 'docs: add comprehensive README for Zoo' (#44) from issue-43-anna into main
438a663 docs: clarify agents are in example config, not pre-configured
884245c Merge branch 'main' into issue-36-greg
Thinking
This is a Go project. The issue is about the job log display β the `block-body` div is sometimes empty, or has excessive whitespace. Let me check the web templates and the livelog package.
Tool
π§ read_file
{"end_line": 100, "path": "internal/web/templates.go", "start_line": 1}
Arguments
{"end_line": 100, "path": "internal/web/templates.go", "start_line": 1}
Result
{"path":"internal/web/templates.go","content":"package web\n\nconst templates = `\n{{define \"layout_head\"}}\n\u003c!doctype html\u003e\n\u003chtml lang=\"en\"\u003e\n\u003chead\u003e\n\u003cmeta charset=\"utf-8\"\u003e\n\u003cmeta name=\"viewport\" content=\"width=device-width, initial-scale=1\"\u003e\n\u003ctitle\u003ezoo\u003c/title\u003e\n\u003cstyle\u003e\n :root {\n --bg: #0f0f13;\n --bg-surface: #1a1a24;\n --bg-surface-hover: #22222e;\n --bg-code: #12121a;\n --border: #2a2a3a;\n --text: #e4e4e8;\n --text-muted: #8888a0;\n --accent: #7c6aef;\n --accent-glow: rgba(124, 106, 239, 0.15);\n --radius: 12px;\n --radius-sm: 8px;\n --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;\n --mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', monospace;\n }\n\n * { margin: 0; padding: 0; box-sizing: border-box; }\n\n body {\n font-family: var(--font);\n background: var(--bg);\n color: var(--text);\n line-height: 1.6;\n min-height: 100vh;\n }\n\n /* ββ Navigation βββββββββββββββββββββββββββββββ */\n nav {\n position: sticky;\n top: 0;\n z-index: 100;\n display: flex;\n align-items: center;\n justify-content: space-between;\n padding: 0 2rem;\n height: 60px;\n background: var(--bg-surface);\n border-bottom: 1px solid var(--border);\n backdrop-filter: blur(12px);\n }\n\n nav .brand {\n display: flex;\n align-items: center;\n gap: 0.6rem;\n font-size: 1.25rem;\n font-weight: 700;\n color: var(--text);\n text-decoration: none;\n letter-spacing: -0.02em;\n }\n\n nav .brand .logo {\n display: inline-flex;\n align-items: center;\n justify-content: center;\n width: 32px;\n height: 32px;\n border-radius: var(--radius-sm);\n background: linear-gradient(135deg, var(--accent), #a78bfa);\n color: #fff;\n font-size: 1rem;\n font-weight: 800;\n }\n\n nav .links {\n display: flex;\n gap: 0.25rem;\n }\n\n nav .links a {\n display: inline-flex;\n align-items: center;\n gap: 0.4rem;\n padding: 0.5rem 1rem;\n border-radius: var(--radius-sm);\n color: var(--text-muted);\n text-decoration: none;\n font-size: 0.9rem;\n font-weight: 500;\n transition: all 0.15s ease;\n }\n\n nav .links a:hover {\n color: var(--text);\n background: var(--bg-surface-hover);\n }\n\n nav .links a.active {","start_line":1,"end_line":100,"total_lines":1004,"truncated":true}
Tool
π§ read_file
{"end_line": 100, "path": "internal/livelog/hub.go", "start_line": 1}
Arguments
{"end_line": 100, "path": "internal/livelog/hub.go", "start_line": 1}
Result
{"path":"internal/livelog/hub.go","content":"// Package livelog is an in-memory pub/sub hub that lets agentrun publish\n// fine-grained, not-yet-persisted events (reasoning/content deltas, tool\n// calls) for a running job, and lets the web dashboard subscribe to them\n// live over SSE. It carries only the tail of a run that hasn't made it\n// into SQLite yet β see Hub.Checkpoint.\npackage livelog\n\nimport \"sync\"\n\ntype Type string\n\nconst (\n\tReasoningStart Type = \"reasoning_start\"\n\tReasoningDelta Type = \"reasoning_delta\"\n\tReasoningEnd Type = \"reasoning_end\"\n\tContentStart Type = \"content_start\"\n\tContentDelta Type = \"content_delta\"\n\tContentEnd Type = \"content_end\"\n\tTool Type = \"tool\"\n\tStatus Type = \"status\"\n)\n\ntype Event struct {\n\tType Type `json:\"type\"`\n\tText string `json:\"text,omitempty\"`\n\tName string `json:\"name,omitempty\"`\n\tArguments string `json:\"arguments,omitempty\"`\n\tResult string `json:\"result,omitempty\"`\n\tError bool `json:\"error,omitempty\"`\n\tStatus string `json:\"status,omitempty\"`\n}\n\n// subChanBuffer bounds how many events a slow subscriber can lag behind\n// by before new events are dropped for it. Generous for a single-user\n// local dashboard; a dropped event just means a subscriber's browser\n// tab misses a chunk and catches up on the next one, never a hang.\nconst subChanBuffer = 256\n\n// maxBufferedEvents caps the per-job replay buffer as a safety net\n// against unbounded growth if a caller forgets to Checkpoint. Ordinary\n// operation clears the buffer far below this on every persisted block.\nconst maxBufferedEvents = 10000\n\ntype stream struct {\n\tmu sync.Mutex\n\tbuf []Event\n\tsubs map[chan Event]struct{}\n}\n\n// Hub fans out per-job Events to any number of live subscribers.\ntype Hub struct {\n\tmu sync.Mutex\n\tjobs map[string]*stream\n}\n\nfunc NewHub() *Hub {\n\treturn \u0026Hub{jobs: make(map[string]*stream)}\n}\n\nfunc (h *Hub) get(jobID string) *stream {\n\th.mu.Lock()\n\tdefer h.mu.Unlock()\n\n\ts, ok := h.jobs[jobID]\n\tif !ok {\n\t\ts = \u0026stream{subs: make(map[chan Event]struct{})}\n\t\th.jobs[jobID] = s\n\t}\n\n\treturn s\n}\n\n// Publish appends ev to jobID's replay buffer and fans it out to every\n// current subscriber. Never blocks: a subscriber whose channel is full\n// simply misses this event.\nfunc (h *Hub) Publish(jobID string, ev Event) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\ts.buf = append(s.buf, ev)\n\tif len(s.buf) \u003e maxBufferedEvents {\n\t\ts.buf = s.buf[len(s.buf)-maxBufferedEvents:]\n\t}\n\n\tfor ch := range s.subs {\n\t\tselect {\n\t\tcase ch \u003c- ev:\n\t\tdefault:\n\t\t}\n\t}\n}\n\n// Checkpoint clears jobID's replay buffer. Call this right after a\n// block derived from buffered events has been durably written to\n// storage, so a subscriber that connects afterward β and therefore\n// already sees that block via the persisted history β is never replayed\n// it a second time over the live channel.\nfunc (h *Hub) Checkpoint(jobID string) {","start_line":1,"end_line":100,"total_lines":164,"truncated":true}
Thinking
Let's take a look at the web.go file, particularly the SSE streaming part and the rendering of blocks.
Tool
π§ read_file
{"end_line": 120, "path": "internal/web/web.go", "start_line": 1}
Arguments
{"end_line": 120, "path": "internal/web/web.go", "start_line": 1}
Result
{"path":"internal/web/web.go","content":"// Package web is zoo's minimal server-rendered dashboard: config\n// overview, live queue/history, and a per-job log tail.\npackage web\n\nimport (\n\t\"encoding/json\"\n\t\"fmt\"\n\t\"html/template\"\n\t\"net/http\"\n\t\"strings\"\n\t\"sync\"\n\t\"time\"\n\n\t\"github.com/abrander/zoo/internal/config\"\n\t\"github.com/abrander/zoo/internal/forgejo\"\n\t\"github.com/abrander/zoo/internal/livelog\"\n\t\"github.com/abrander/zoo/internal/store\"\n)\n\ntype Server struct {\n\tcfg *config.Config\n\tstore *store.Store\n\thub *livelog.Hub\n\tfg *forgejo.Client\n\ttmpl *template.Template\n\n\tavatarMu sync.Mutex\n\tavatarCache map[string]avatarCacheEntry\n}\n\n// avatarCacheTTL bounds how long a resolved avatar URL is trusted before\n// it's re-fetched from Forgejo. Avatars rarely change, but a user can\n// re-upload one (which changes its URL), so the cache expires instead of\n// living for the process lifetime.\nconst avatarCacheTTL = time.Hour\n\ntype avatarCacheEntry struct {\n\turl string\n\tfetchedAt time.Time\n}\n\nfunc New(cfg *config.Config, st *store.Store, hub *livelog.Hub, fg *forgejo.Client) *Server {\n\treturn \u0026Server{\n\t\tcfg: cfg,\n\t\tstore: st,\n\t\thub: hub,\n\t\tfg: fg,\n\t\ttmpl: template.Must(template.New(\"\").Parse(templates)),\n\t\tavatarCache: map[string]avatarCacheEntry{},\n\t}\n}\n\n// Handler returns the dashboard's http.Handler, gated by config.Web's\n// bearer token if one is set.\nfunc (s *Server) Handler() http.Handler {\n\tmux := http.NewServeMux()\n\n\tmux.HandleFunc(\"GET /{$}\", s.handleIndex)\n\tmux.HandleFunc(\"GET /jobs\", s.handleJobs)\n\tmux.HandleFunc(\"GET /jobs/{id}\", s.handleJobDetail)\n\tmux.HandleFunc(\"GET /jobs/{id}/events\", s.handleJobEvents)\n\n\treturn s.authMiddleware(mux)\n}\n\nfunc (s *Server) authMiddleware(next http.Handler) http.Handler {\n\tif s.cfg.Web == nil || s.cfg.Web.Token == \"\" {\n\t\treturn next\n\t}\n\n\ttoken := s.cfg.Web.Token\n\n\treturn http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {\n\t\tauth := r.Header.Get(\"Authorization\")\n\t\tif auth != \"Bearer \"+token {\n\t\t\tw.Header().Set(\"WWW-Authenticate\", `Bearer realm=\"zoo\"`)\n\t\t\thttp.Error(w, \"unauthorized\", http.StatusUnauthorized)\n\n\t\t\treturn\n\t\t}\n\n\t\tnext.ServeHTTP(w, r)\n\t})\n}\n\nfunc (s *Server) handleIndex(w http.ResponseWriter, r *http.Request) {\n\t// Fetch active (pending or running) jobs for the dashboard overview.\n\t// We fetch more than we display so we can filter to just active ones.\n\tallJobs, err := s.store.ListJobs(r.Context(), 200)\n\tif err != nil {\n\t\thttp.Error(w, err.Error(), http.StatusInternalServerError)\n\t\treturn\n\t}\n\n\t// Collect unique agent names from active jobs.\n\tvar agentNames []string\n\tseenAgents := make(map[string]bool)\n\n\tvar activeJobs []activeJobRow\n\tfor _, j := range allJobs {\n\t\tif j.Status != store.JobPending \u0026\u0026 j.Status != store.JobRunning {\n\t\t\tcontinue\n\t\t}\n\t\tif !seenAgents[j.Agent] {\n\t\t\tseenAgents[j.Agent] = true\n\t\t\tagentNames = append(agentNames, j.Agent)\n\t\t}\n\t\tactiveJobs = append(activeJobs, activeJobRow{\n\t\t\tJob: j,\n\t\t\tAvatarURL: s.avatarFor(j.Agent),\n\t\t})\n\t}\n\n\ttype indexData struct {\n\t\t*config.Config\n\t\tActiveJobs []activeJobRow\n\t}\n\n\ts.render(w, \"index\", indexData{\n\t\tConfig: s.cfg,","start_line":1,"end_line":120,"total_lines":374,"truncated":true}
Thinking
Let's take a look at the rest of web.go, particularly the job detail handler and the SSE events handler.
Tool
π§ read_file
{"end_line": 374, "path": "internal/web/web.go", "start_line": 120}
Arguments
{"end_line": 374, "path": "internal/web/web.go", "start_line": 120}
Result
{"path":"internal/web/web.go","content":"\t\tConfig: s.cfg,\n\t\tActiveJobs: activeJobs,\n\t})\n}\n\n// activeJobRow is a store.Job enriched with the agent's avatar URL.\ntype activeJobRow struct {\n\tstore.Job\n\tAvatarURL string\n}\n\n// jobRow is a store.Job plus the agent's Forgejo avatar, resolved for the\n// jobs table so it's immediately clear who is running each job.\ntype jobRow struct {\n\tstore.Job\n\tAvatarURL string\n}\n\nfunc (s *Server) handleJobs(w http.ResponseWriter, r *http.Request) {\n\tjobs, err := s.store.ListJobs(r.Context(), 200)\n\tif err != nil {\n\t\thttp.Error(w, err.Error(), http.StatusInternalServerError)\n\n\t\treturn\n\t}\n\n\trows := make([]jobRow, 0, len(jobs))\n\n\tfor _, j := range jobs {\n\t\trows = append(rows, jobRow{Job: j, AvatarURL: s.avatarFor(j.Agent)})\n\t}\n\n\ts.render(w, \"jobs\", rows)\n}\n\n// avatarFor returns the Forgejo avatar URL of the agent named username,\n// or \"\" if it can't be resolved (no Forgejo client configured, unknown\n// user, API error). The dashboard must never fail to render because of a\n// missing avatar, so every failure mode degrades to no image. Results are\n// cached per username for avatarCacheTTL so a page refresh doesn't turn\n// into one GetUserInfo call per unique agent.\nfunc (s *Server) avatarFor(username string) string {\n\tif s.fg == nil || username == \"\" {\n\t\treturn \"\"\n\t}\n\n\ts.avatarMu.Lock()\n\n\tif e, ok := s.avatarCache[username]; ok \u0026\u0026 time.Since(e.fetchedAt) \u003c avatarCacheTTL {\n\t\ts.avatarMu.Unlock()\n\n\t\treturn e.url\n\t}\n\n\ts.avatarMu.Unlock()\n\n\tprofile, err := s.fg.AgentProfile(username)\n\tif err != nil {\n\t\treturn \"\"\n\t}\n\n\ts.avatarMu.Lock()\n\ts.avatarCache[username] = avatarCacheEntry{url: profile.AvatarURL, fetchedAt: time.Now()}\n\ts.avatarMu.Unlock()\n\n\treturn profile.AvatarURL\n}\n\n// toolBlock is the parsed form of a stream=\"tool\" store.LogLine, for the\n// template to render as a single collapsed detail.\ntype toolBlock struct {\n\tName string\n\tArguments string\n\tResult string\n\tError bool\n}\n\n// block is one self-contained, already-complete unit of job output: a\n// finished reasoning or assistant-message block, a finished tool call,\n// or a misc system note. Unlike the old flat log view, one store.LogLine\n// maps to exactly one block β grouping/streaming happens upstream, when\n// agentrun persists the row.\ntype block struct {\n\tKind string // \"reasoning\" | \"content\" | \"tool\" | \"system\"\n\tText string\n\tTool *toolBlock\n}\n\nfunc buildBlocks(logs []store.LogLine) []block {\n\tblocks := make([]block, 0, len(logs))\n\n\tfor _, l := range logs {\n\t\tswitch l.Stream {\n\t\tcase \"reasoning\", \"content\":\n\t\t\t// Model output routinely starts/ends with newlines. The block\n\t\t\t// body renders with white-space: pre-wrap, so those would show\n\t\t\t// up as visible blank lines inflating the block's height. Trim\n\t\t\t// them for display (internal newlines are kept) and drop\n\t\t\t// blocks that are nothing but whitespace.\n\t\t\ttext := strings.TrimSpace(l.Line)\n\t\t\tif text == \"\" {\n\t\t\t\tcontinue\n\t\t\t}\n\t\t\tblocks = append(blocks, block{Kind: l.Stream, Text: text})\n\n\t\tcase \"tool\":\n\t\t\tvar entry store.ToolLogEntry\n\t\t\tif err := json.Unmarshal([]byte(l.Line), \u0026entry); err != nil {\n\t\t\t\tblocks = append(blocks, block{Kind: \"system\", Text: l.Line})\n\n\t\t\t\tcontinue\n\t\t\t}\n\n\t\t\tblocks = append(blocks, block{Kind: \"tool\", Tool: \u0026toolBlock{\n\t\t\t\tName: entry.Name,\n\t\t\t\tArguments: entry.Arguments,\n\t\t\t\tResult: entry.Result,\n\t\t\t\tError: entry.Error,\n\t\t\t}})\n\n\t\tdefault:\n\t\t\tblocks = append(blocks, block{Kind: \"system\", Text: l.Line})\n\t\t}\n\t}\n\n\treturn blocks\n}\n\nfunc (s *Server) handleJobDetail(w http.ResponseWriter, r *http.Request) {\n\tid := r.PathValue(\"id\")\n\n\tjob, err := s.store.GetJob(r.Context(), id)\n\tif err != nil {\n\t\thttp.Error(w, \"job not found\", http.StatusNotFound)\n\n\t\treturn\n\t}\n\n\tlogs, err := s.store.TailLogs(r.Context(), id, -1)\n\tif err != nil {\n\t\thttp.Error(w, err.Error(), http.StatusInternalServerError)\n\n\t\treturn\n\t}\n\n\ts.render(w, \"job_detail\", struct {\n\t\tJob store.Job\n\t\tBlocks []block\n\t\tLive bool\n\t\tAvatarURL string\n\t}{job, buildBlocks(logs), job.Status == store.JobPending || job.Status == store.JobRunning, s.avatarFor(job.Agent)})\n}\n\n// handleJobEvents streams job jobID's live output as Server-Sent\n// Events. It only ever carries events for the current, not-yet-persisted\n// block (see livelog.Hub.Checkpoint) β everything already written to\n// the store is rendered once, statically, by handleJobDetail. If the\n// job isn't live, the response just ends immediately and the client\n// falls back to the static page.\nfunc (s *Server) handleJobEvents(w http.ResponseWriter, r *http.Request) {\n\tid := r.PathValue(\"id\")\n\n\tjob, err := s.store.GetJob(r.Context(), id)\n\tif err != nil {\n\t\thttp.Error(w, \"job not found\", http.StatusNotFound)\n\n\t\treturn\n\t}\n\n\tif job.Status != store.JobPending \u0026\u0026 job.Status != store.JobRunning {\n\t\treturn\n\t}\n\n\tflusher, ok := w.(http.Flusher)\n\tif !ok {\n\t\thttp.Error(w, \"streaming unsupported\", http.StatusInternalServerError)\n\n\t\treturn\n\t}\n\n\tw.Header().Set(\"Content-Type\", \"text/event-stream\")\n\tw.Header().Set(\"Cache-Control\", \"no-cache\")\n\tw.Header().Set(\"Connection\", \"keep-alive\")\n\tw.WriteHeader(http.StatusOK)\n\n\tbuffered, ch, cancel := s.hub.Subscribe(id)\n\tdefer cancel()\n\n\twrite := func(ev livelog.Event) bool {\n\t\tdata, err := json.Marshal(ev)\n\t\tif err != nil {\n\t\t\treturn true\n\t\t}\n\n\t\tif _, err := fmt.Fprintf(w, \"data: %s\\n\\n\", data); err != nil {\n\t\t\treturn false\n\t\t}\n\n\t\tflusher.Flush()\n\n\t\treturn true\n\t}\n\n\tfor _, ev := range buffered {\n\t\tif !write(ev) {\n\t\t\treturn\n\t\t}\n\t}\n\n\theartbeat := time.NewTicker(15 * time.Second)\n\tdefer heartbeat.Stop()\n\n\tfor {\n\t\tselect {\n\t\tcase ev, ok := \u003c-ch:\n\t\t\tif !ok {\n\t\t\t\treturn\n\t\t\t}\n\n\t\t\tif !write(ev) {\n\t\t\t\treturn\n\t\t\t}\n\n\t\t\tif ev.Type == livelog.Status {\n\t\t\t\treturn\n\t\t\t}\n\n\t\tcase \u003c-heartbeat.C:\n\t\t\tif _, err := fmt.Fprint(w, \": heartbeat\\n\\n\"); err != nil {\n\t\t\t\treturn\n\t\t\t}\n\n\t\t\tflusher.Flush()\n\n\t\tcase \u003c-r.Context().Done():\n\t\t\treturn\n\t\t}\n\t}\n}\n\nfunc (s *Server) render(w http.ResponseWriter, name string, data any) {\n\tw.Header().Set(\"Content-Type\", \"text/html; charset=utf-8\")\n\n\t// Every page here reflects live, fast-changing state (job status, log\n\t// blocks). Without this, browsers are free to serve a stale cached\n\t// copy of the job detail page on a same-URL navigation β including\n\t// the auto location.reload() a job's SSE stream triggers when it\n\t// finishes β which looks exactly like blocks that were visible while\n\t// streaming vanishing once the page reloads.\n\tw.Header().Set(\"Cache-Control\", \"no-store\")\n\n\tif err := s.tmpl.ExecuteTemplate(w, name, data); err != nil {\n\t\thttp.Error(w, err.Error(), http.StatusInternalServerError)\n\t}\n}","start_line":120,"end_line":374,"total_lines":374,"truncated":false}
Thinking
Next, let's look at the job_detail template to check how blocks are rendered, and how the SSE events are handled on the client side (JavaScript). I'll search for "block-body" in the template.
Tool
π§ grep_search
{"context_after": 10, "context_before": 5, "query": "block-body"}
Arguments
{"context_after": 10, "context_before": 5, "query": "block-body"}
Result
/project/internal/web/templates.go-444- color: var(--text-muted);
/project/internal/web/templates.go-445- font-weight: 600;
/project/internal/web/templates.go-446- margin-bottom: 0.35rem;
/project/internal/web/templates.go-447- }
/project/internal/web/templates.go-448-
/project/internal/web/templates.go:449: .block-body {
/project/internal/web/templates.go-450- font-family: var(--font);
/project/internal/web/templates.go-451- font-size: 0.9rem;
/project/internal/web/templates.go-452- line-height: 1.6;
/project/internal/web/templates.go-453- color: var(--text);
/project/internal/web/templates.go-454- white-space: pre-wrap;
/project/internal/web/templates.go-455- word-break: break-word;
/project/internal/web/templates.go-456- }
/project/internal/web/templates.go-457-
/project/internal/web/templates.go-458- .block-reasoning,
/project/internal/web/templates.go-459- .block-content {
--
/project/internal/web/templates.go-464- .block-reasoning {
/project/internal/web/templates.go-465- background: rgba(124, 106, 239, 0.06);
/project/internal/web/templates.go-466- border-left: 3px solid var(--accent);
/project/internal/web/templates.go-467- }
/project/internal/web/templates.go-468-
/project/internal/web/templates.go:469: .block-reasoning .block-body {
/project/internal/web/templates.go-470- color: var(--text-muted);
/project/internal/web/templates.go-471- font-style: italic;
/project/internal/web/templates.go-472- }
/project/internal/web/templates.go-473-
/project/internal/web/templates.go-474- .block-content {
/project/internal/web/templates.go-475- background: var(--bg-surface);
/project/internal/web/templates.go-476- border: 1px solid var(--border);
/project/internal/web/templates.go-477- }
/project/internal/web/templates.go-478-
/project/internal/web/templates.go-479- .block-system {
--
/project/internal/web/templates.go-552- }
/project/internal/web/templates.go-553-
/project/internal/web/templates.go-554- .block-tool-error { border-left-color: #ef4444; }
/project/internal/web/templates.go-555- .block-tool-error .tool-badge { background: rgba(239, 68, 68, 0.15); color: #ef4444; }
/project/internal/web/templates.go-556-
/project/internal/web/templates.go:557: .block-tool .block-body {
/project/internal/web/templates.go-558- padding: 0 1.1rem 1rem;
/project/internal/web/templates.go-559- border-top: 1px solid var(--border);
/project/internal/web/templates.go-560- /* Unlike a reasoning/content block, this wraps element children
/project/internal/web/templates.go-561- (labels + <pre>s), not raw text, so it must not inherit the base
/project/internal/web/templates.go:562: .block-body's white-space: pre-wrap β that would render the
/project/internal/web/templates.go-563- template source's own whitespace between those child tags as
/project/internal/web/templates.go-564- visible blank lines. */
/project/internal/web/templates.go-565- white-space: normal;
/project/internal/web/templates.go-566- }
/project/internal/web/templates.go-567-
/project/internal/web/templates.go-568- .block-tool .tool-section-label {
/project/internal/web/templates.go-569- font-size: 0.72rem;
/project/internal/web/templates.go-570- text-transform: uppercase;
/project/internal/web/templates.go-571- letter-spacing: 0.05em;
/project/internal/web/templates.go-572- color: var(--text-muted);
--
/project/internal/web/templates.go-846- <div class="log-container" id="log">
/project/internal/web/templates.go-847- {{range .Blocks}}
/project/internal/web/templates.go-848- {{if eq .Kind "reasoning"}}
/project/internal/web/templates.go-849- <div class="block block-reasoning">
/project/internal/web/templates.go-850- <div class="block-label">Thinking</div>
/project/internal/web/templates.go:851: <div class="block-body">{{.Text}}</div>
/project/internal/web/templates.go-852- </div>
/project/internal/web/templates.go-853- {{else if eq .Kind "content"}}
/project/internal/web/templates.go-854- <div class="block block-content">
/project/internal/web/templates.go:855: <div class="block-body">{{.Text}}</div>
/project/internal/web/templates.go-856- </div>
/project/internal/web/templates.go-857- {{else if eq .Kind "tool"}}
/project/internal/web/templates.go-858- <details class="block block-tool{{if .Tool.Error}} block-tool-error{{end}}">
/project/internal/web/templates.go-859- <summary>
/project/internal/web/templates.go-860- <span class="tool-badge">Tool</span>
/project/internal/web/templates.go-861- <span class="tool-summary-text">
/project/internal/web/templates.go-862- <span class="tool-name">π§ {{.Tool.Name}}</span>
/project/internal/web/templates.go-863- <span class="tool-args-preview">{{.Tool.Arguments}}</span>
/project/internal/web/templates.go-864- </span>
/project/internal/web/templates.go-865- </summary>
/project/internal/web/templates.go:866: <div class="block-body">
/project/internal/web/templates.go-867- <div class="tool-section-label">Arguments</div>
/project/internal/web/templates.go-868- <pre>{{.Tool.Arguments}}</pre>
/project/internal/web/templates.go-869- <div class="tool-section-label">Result</div>
/project/internal/web/templates.go-870- <pre>{{.Tool.Result}}</pre>
/project/internal/web/templates.go-871- </div>
/project/internal/web/templates.go-872- </details>
/project/internal/web/templates.go-873- {{else}}
/project/internal/web/templates.go-874- <div class="block block-system">{{.Text}}</div>
/project/internal/web/templates.go-875- {{end}}
/project/internal/web/templates.go-876- {{end}}
--
/project/internal/web/templates.go-896- l.className = "block-label";
/project/internal/web/templates.go-897- l.textContent = label;
/project/internal/web/templates.go-898- div.appendChild(l);
/project/internal/web/templates.go-899- }
/project/internal/web/templates.go-900- var body = document.createElement("div");
/project/internal/web/templates.go:901: body.className = "block-body";
/project/internal/web/templates.go-902- div.appendChild(body);
/project/internal/web/templates.go-903- log.appendChild(div);
/project/internal/web/templates.go-904- return body;
/project/internal/web/templates.go-905- }
/project/internal/web/templates.go-906-
/project/internal/web/templates.go-907- function newToolBlock(ev) {
Thinking
Alright, let's take a look at the JavaScript part of the job_detail template β the SSE client. I'll read from around line 840 to the end of the template.
Tool
π§ read_file
{"end_line": 1004, "path": "internal/web/templates.go", "start_line": 820}
Arguments
{"end_line": 1004, "path": "internal/web/templates.go", "start_line": 820}
Result
{"path":"internal/web/templates.go","content":" {{.Job.Status}}\n \u003c/span\u003e\n \u003c/span\u003e\n \u003c/div\u003e\n \u003cdiv class=\"job-meta-item\"\u003e\n \u003cspan class=\"label\"\u003eEvent\u003c/span\u003e\n \u003cspan class=\"value\"\u003e{{.Job.EventKind}} on \u003ccode\u003e{{.Job.Owner}}/{{.Job.Repo}}#{{.Job.IssueIndex}}\u003c/code\u003e\u003c/span\u003e\n \u003c/div\u003e\n \u003cdiv class=\"job-meta-item\"\u003e\n \u003cspan class=\"label\"\u003eAgent\u003c/span\u003e\n \u003cspan class=\"value\"\u003e\n \u003cspan class=\"agent\"\u003e\n {{if .AvatarURL}}\u003cimg class=\"agent-avatar\" src=\"{{.AvatarURL}}\" alt=\"{{.Job.Agent}}\" title=\"{{.Job.Agent}}\"\u003e{{end}}\n \u003cstrong\u003e{{.Job.Agent}}\u003c/strong\u003e\n \u003c/span\u003e\n \u003c/span\u003e\n \u003c/div\u003e\n {{if .Job.Error}}\n \u003cdiv class=\"job-meta-item\"\u003e\n \u003cspan class=\"label\"\u003eError\u003c/span\u003e\n \u003cspan class=\"value error-text\"\u003e{{.Job.Error}}\u003c/span\u003e\n \u003c/div\u003e\n {{end}}\n \u003c/div\u003e\n\n \u003ch2\u003eLog\u003c/h2\u003e\n \u003cdiv class=\"log-container\" id=\"log\"\u003e\n {{range .Blocks}}\n {{if eq .Kind \"reasoning\"}}\n \u003cdiv class=\"block block-reasoning\"\u003e\n \u003cdiv class=\"block-label\"\u003eThinking\u003c/div\u003e\n \u003cdiv class=\"block-body\"\u003e{{.Text}}\u003c/div\u003e\n \u003c/div\u003e\n {{else if eq .Kind \"content\"}}\n \u003cdiv class=\"block block-content\"\u003e\n \u003cdiv class=\"block-body\"\u003e{{.Text}}\u003c/div\u003e\n \u003c/div\u003e\n {{else if eq .Kind \"tool\"}}\n \u003cdetails class=\"block block-tool{{if .Tool.Error}} block-tool-error{{end}}\"\u003e\n \u003csummary\u003e\n \u003cspan class=\"tool-badge\"\u003eTool\u003c/span\u003e\n \u003cspan class=\"tool-summary-text\"\u003e\n \u003cspan class=\"tool-name\"\u003eπ§ {{.Tool.Name}}\u003c/span\u003e\n \u003cspan class=\"tool-args-preview\"\u003e{{.Tool.Arguments}}\u003c/span\u003e\n \u003c/span\u003e\n \u003c/summary\u003e\n \u003cdiv class=\"block-body\"\u003e\n \u003cdiv class=\"tool-section-label\"\u003eArguments\u003c/div\u003e\n \u003cpre\u003e{{.Tool.Arguments}}\u003c/pre\u003e\n \u003cdiv class=\"tool-section-label\"\u003eResult\u003c/div\u003e\n \u003cpre\u003e{{.Tool.Result}}\u003c/pre\u003e\n \u003c/div\u003e\n \u003c/details\u003e\n {{else}}\n \u003cdiv class=\"block block-system\"\u003e{{.Text}}\u003c/div\u003e\n {{end}}\n {{end}}\n \u003c/div\u003e\n\n {{if .Live}}\n \u003cscript\u003e\n (function() {\n var jobID = {{.Job.ID}};\n var log = document.getElementById(\"log\");\n var reasoningBody = null;\n var contentBody = null;\n\n function nearBottom() {\n return (window.innerHeight + window.scrollY) \u003e= (document.body.offsetHeight - 80);\n }\n\n function newBlock(kind, label) {\n var div = document.createElement(\"div\");\n div.className = \"block block-\" + kind;\n if (label) {\n var l = document.createElement(\"div\");\n l.className = \"block-label\";\n l.textContent = label;\n div.appendChild(l);\n }\n var body = document.createElement(\"div\");\n body.className = \"block-body\";\n div.appendChild(body);\n log.appendChild(div);\n return body;\n }\n\n function newToolBlock(ev) {\n var details = document.createElement(\"details\");\n details.className = \"block block-tool\" + (ev.error ? \" block-tool-error\" : \"\");\n\n var summary = document.createElement(\"summary\");\n\n var badge = document.createElement(\"span\");\n badge.className = \"tool-badge\";\n badge.textContent = \"Tool\";\n\n var text = document.createElement(\"span\");\n text.className = \"tool-summary-text\";\n\n var name = document.createElement(\"span\");\n name.className = \"tool-name\";\n name.textContent = \"π§ \" + ev.name;\n\n var preview = document.createElement(\"span\");\n preview.className = \"tool-args-preview\";\n preview.textContent = ev.arguments;\n\n text.appendChild(name);\n text.appendChild(preview);\n summary.appendChild(badge);\n summary.appendChild(text);\n details.appendChild(summary);\n\n var body = document.createElement(\"div\");\n body.className = \"block-body\";\n\n var argsLabel = document.createElement(\"div\");\n argsLabel.className = \"tool-section-label\";\n argsLabel.textContent = \"Arguments\";\n var argsPre = document.createElement(\"pre\");\n argsPre.textContent = ev.arguments;\n\n var resultLabel = document.createElement(\"div\");\n resultLabel.className = \"tool-section-label\";\n resultLabel.textContent = \"Result\";\n var resultPre = document.createElement(\"pre\");\n resultPre.textContent = ev.result;\n\n body.appendChild(argsLabel);\n body.appendChild(argsPre);\n body.appendChild(resultLabel);\n body.appendChild(resultPre);\n details.appendChild(body);\n log.appendChild(details);\n }\n\n var es = new EventSource(\"/jobs/\" + jobID + \"/events\");\n\n es.onmessage = function(e) {\n var ev = JSON.parse(e.data);\n var shouldScroll = nearBottom();\n\n switch (ev.type) {\n case \"reasoning_start\":\n reasoningBody = newBlock(\"reasoning\", \"Thinking\");\n break;\n case \"reasoning_delta\":\n if (reasoningBody) reasoningBody.textContent += ev.text;\n break;\n case \"reasoning_end\":\n // Model output routinely starts/ends with newlines; drop them\n // so the finished block matches the static (trimmed) view.\n if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();\n reasoningBody = null;\n break;\n case \"content_start\":\n contentBody = newBlock(\"content\", null);\n break;\n case \"content_delta\":\n if (contentBody) contentBody.textContent += ev.text;\n break;\n case \"content_end\":\n if (contentBody) contentBody.textContent = contentBody.textContent.trim();\n contentBody = null;\n break;\n case \"tool\":\n newToolBlock(ev);\n break;\n case \"status\":\n es.close();\n location.reload();\n return;\n }\n\n if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);\n };\n })();\n \u003c/script\u003e\n {{end}}\n\u003c/div\u003e\n\u003c/body\u003e\n\u003c/html\u003e\n{{end}}\n`","start_line":820,"end_line":1004,"total_lines":1004,"truncated":false}
Thinking
Now I understand the client side. Let's look at the server side: how does agentrun publish events to the livelog hub, and how does it persist blocks? Let me check `internal/agentrun/loop.go` and `run.go`.
Tool
π§ read_file
{"end_line": 120, "path": "internal/agentrun/loop.go", "start_line": 1}
Arguments
{"end_line": 120, "path": "internal/agentrun/loop.go", "start_line": 1}
Result
{"path":"internal/agentrun/loop.go","content":"package agentrun\n\nimport (\n\t\"context\"\n\t\"fmt\"\n\t\"io\"\n\n\t\"github.com/abrander/zoo/internal/llm\"\n\t\"github.com/abrander/zoo/internal/tools\"\n)\n\n// Hooks lets a caller observe a runLoop invocation live, as the model\n// streams and tool calls execute, in addition to the final []llm.Message\n// it returns. Any of these may be nil.\ntype Hooks struct {\n\t// OnReasoningDelta and OnContentDelta fire with just the newly\n\t// streamed text for the current turn, not the accumulated total.\n\tOnReasoningDelta func(delta string)\n\tOnContentDelta func(delta string)\n\n\t// OnTurnEnd fires once per completed streamer round-trip, after the\n\t// model's message for that turn is fully received and before any of\n\t// its tool calls run.\n\tOnTurnEnd func()\n\n\t// OnTool fires once per tool call, after it has run.\n\tOnTool func(name, arguments, result string, toolErr bool)\n}\n\n// runLoop is a headless port of ../a's App.generate(): send messages +\n// tool defs, get a completion, run any tool_calls and append their\n// results, repeat until a plain finish or ctx is done.\nfunc runLoop(ctx context.Context, client *llm.Client, toolsCtx tools.Context, messages []llm.Message, hooks Hooks) ([]llm.Message, error) {\n\tfor {\n\t\tif err := ctx.Err(); err != nil {\n\t\t\treturn messages, err\n\t\t}\n\n\t\tstreamer, err := client.StreamChatCompletion(ctx, \u0026llm.ChatCompletionRequest{\n\t\t\tMessages: messages,\n\t\t\tStream: true,\n\t\t\tTools: tools.All(),\n\t\t})\n\t\tif err != nil {\n\t\t\treturn messages, fmt.Errorf(\"chat completion: %w\", err)\n\t\t}\n\n\t\tvar completion *llm.ChatCompletion\n\n\t\tvar prevContent, prevReasoning string\n\n\t\tfor {\n\t\t\tc, err := streamer.Get()\n\t\t\tif err == io.EOF {\n\t\t\t\tbreak\n\t\t\t}\n\n\t\t\tif err != nil {\n\t\t\t\treturn messages, fmt.Errorf(\"stream completion: %w\", err)\n\t\t\t}\n\n\t\t\tcompletion = c\n\n\t\t\tif len(c.Choices) \u003e 0 {\n\t\t\t\tmsg := c.Choices[0].Message\n\n\t\t\t\tif hooks.OnReasoningDelta != nil \u0026\u0026 len(msg.ReasoningContent) \u003e len(prevReasoning) {\n\t\t\t\t\thooks.OnReasoningDelta(msg.ReasoningContent[len(prevReasoning):])\n\t\t\t\t}\n\t\t\t\tprevReasoning = msg.ReasoningContent\n\n\t\t\t\tif hooks.OnContentDelta != nil \u0026\u0026 len(msg.Content) \u003e len(prevContent) {\n\t\t\t\t\thooks.OnContentDelta(msg.Content[len(prevContent):])\n\t\t\t\t}\n\t\t\t\tprevContent = msg.Content\n\t\t\t}\n\t\t}\n\n\t\tif hooks.OnTurnEnd != nil {\n\t\t\thooks.OnTurnEnd()\n\t\t}\n\n\t\tif completion == nil || len(completion.Choices) == 0 {\n\t\t\treturn messages, fmt.Errorf(\"model returned an empty completion\")\n\t\t}\n\n\t\tchoice := completion.Choices[0]\n\t\tmessages = append(messages, choice.Message)\n\n\t\tif choice.FinishReason != \"tool_calls\" || len(choice.Message.ToolCalls) == 0 {\n\t\t\treturn messages, nil\n\t\t}\n\n\t\tfor _, tc := range choice.Message.ToolCalls {\n\t\t\tif err := ctx.Err(); err != nil {\n\t\t\t\treturn messages, err\n\t\t\t}\n\n\t\t\tresult, err := tools.Call(toolsCtx, tc.FunctionCall)\n\n\t\t\ttoolErr := err != nil\n\t\t\tif toolErr {\n\t\t\t\tresult = fmt.Sprintf(\"ERROR CALLING TOOL: %s\", err.Error())\n\t\t\t}\n\n\t\t\tif hooks.OnTool != nil {\n\t\t\t\thooks.OnTool(tc.FunctionCall.Name, tc.FunctionCall.Arguments, result, toolErr)\n\t\t\t}\n\n\t\t\tmessages = append(messages, llm.Message{\n\t\t\t\tRole: \"tool\",\n\t\t\t\tContent: result,\n\t\t\t\tToolCallID: tc.Id,\n\t\t\t\tName: tc.FunctionCall.Name,\n\t\t\t})\n\t\t}\n\t}\n}","start_line":1,"end_line":118,"total_lines":118,"truncated":false}
Thinking
Next, let's look at run.go to check how the hooks are wired up to the livelog hub and the store.
Tool
π§ read_file
{"end_line": 150, "path": "internal/agentrun/run.go", "start_line": 1}
Arguments
{"end_line": 150, "path": "internal/agentrun/run.go", "start_line": 1}
Result
{"path":"internal/agentrun/run.go","content":"// Package agentrun creates the throwaway per-job environment an agent\n// runs in: a Docker container with the agent's git working tree cloned\n// inside it (authenticated with the agent's own Forgejo token), the\n// triggering event written to /event, and the tool-calling loop\n// (internal/llm + internal/tools) driven against it.\npackage agentrun\n\nimport (\n\t\"context\"\n\t_ \"embed\"\n\t\"encoding/json\"\n\t\"fmt\"\n\t\"log/slog\"\n\t\"os\"\n\t\"path/filepath\"\n\t\"strings\"\n\t\"sync\"\n\t\"time\"\n\n\t\"github.com/abrander/zoo/internal/config\"\n\t\"github.com/abrander/zoo/internal/forgejo\"\n\t\"github.com/abrander/zoo/internal/livelog\"\n\t\"github.com/abrander/zoo/internal/llm\"\n\t\"github.com/abrander/zoo/internal/store\"\n)\n\n//go:embed system.md\nvar defaultSystemPrompt string\n\n// DefaultTimeout bounds a single agent run's wall-clock time if the\n// caller doesn't override it.\nconst DefaultTimeout = 120 * time.Minute\n\ntype Runner struct {\n\tdocker *dockerRuntime\n\tforgejo *forgejo.Client\n\tstore *store.Store\n\thub *livelog.Hub\n\tcfg *config.Config\n\tlogger *slog.Logger\n\ttimeout time.Duration\n\tkeepOnFailure bool\n\n\tagentClientsMu sync.Mutex\n\tagentClients map[string]*forgejo.Client\n}\n\nfunc NewRunner(cfg *config.Config, fg *forgejo.Client, st *store.Store, hub *livelog.Hub, logger *slog.Logger, timeout time.Duration, keepOnFailure bool) (*Runner, error) {\n\tdocker, err := newDockerRuntime()\n\tif err != nil {\n\t\treturn nil, err\n\t}\n\n\tif timeout \u003c= 0 {\n\t\ttimeout = DefaultTimeout\n\t}\n\n\treturn \u0026Runner{\n\t\tdocker: docker,\n\t\tforgejo: fg,\n\t\tstore: st,\n\t\thub: hub,\n\t\tcfg: cfg,\n\t\tlogger: logger,\n\t\ttimeout: timeout,\n\t\tkeepOnFailure: keepOnFailure,\n\t\tagentClients: make(map[string]*forgejo.Client),\n\t}, nil\n}\n\n// forgejoAs returns a Forgejo client that authenticates as the given\n// agent (using the agent's own token from config). This lets each agent\n// act as themselves on Forgejo without needing a global token with sudo\n// privileges. Clients are built once per agent and cached, since\n// constructing one costs an extra API round trip.\n//\n// If the agent has no token configured, falls back to the shared zoo\n// identity so existing deployments without per-agent tokens still work.\nfunc (r *Runner) forgejoAs(agentName, token string) *forgejo.Client {\n\tr.agentClientsMu.Lock()\n\tdefer r.agentClientsMu.Unlock()\n\n\tif c, ok := r.agentClients[agentName]; ok {\n\t\treturn c\n\t}\n\n\tvar c *forgejo.Client\n\tif token != \"\" {\n\t\tc = r.forgejo.As(token)\n\t} else {\n\t\t// Fallback: use shared identity. Optionally log a warning\n\t\t// if we ever want to enforce per-agent tokens.\n\t\tc = r.forgejo\n\t}\n\n\tr.agentClients[agentName] = c\n\n\treturn c\n}\n\n// Run implements scheduler.Runner.\nfunc (r *Runner) Run(ctx context.Context, jobID string, agent config.AgentConfig, llmCfg config.LLM, dockerImage string, ev forgejo.Event) error {\n\tctx, cancel := context.WithTimeout(ctx, r.timeout)\n\tdefer cancel()\n\n\tlogger := r.logger.With(\"job\", jobID, \"agent\", agent.Name)\n\n\trepoInfo, err := r.forgejo.RepositoryInfo(ev.Owner, ev.Repo)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"look up repository: %w\", err)\n\t}\n\n\tworkDir, err := os.MkdirTemp(\"\", \"zoo-run-*\")\n\tif err != nil {\n\t\treturn fmt.Errorf(\"create work dir: %w\", err)\n\t}\n\n\tsucceeded := false\n\n\tdefer func() {\n\t\tif succeeded || !r.keepOnFailure {\n\t\t\tos.RemoveAll(workDir)\n\t\t} else {\n\t\t\tlogger.Warn(\"keeping work dir after failure\", \"dir\", workDir)\n\t\t}\n\t}()\n\n\t// The container bind-mounts projectDir as /project and does the\n\t// initial clone into it, so the (empty) directory must exist on the\n\t// host before the container is created β otherwise Docker would\n\t// create it itself, root-owned.\n\tprojectDir := filepath.Join(workDir, \"project\")\n\n\tif err := os.MkdirAll(projectDir, 0o755); err != nil {\n\t\treturn fmt.Errorf(\"create project dir: %w\", err)\n\t}\n\n\t// A pr:review run works on the PR's own head branch, so the agent's\n\t// commits push straight to the PR. Every other event kind branches\n\t// off the default branch as usual.\n\tvar review *forgejo.ReviewDetail\n\tbranch := fmt.Sprintf(\"issue-%d-%s\", ev.Index, agent.Name)\n\n\tif ev.Kind == forgejo.EventPRReview {\n\t\t// Always fetch the current head ref, not just when the event\n\t\t// lacks one (the polling path doesn't carry it): the webhook's\n\t\t// copy could be stale if the PR's head branch was renamed since\n\t\t// the review, and the push target depends on it.\n\t\theadRef := ev.HeadRef\n","start_line":1,"end_line":150,"total_lines":437,"truncated":true}
Thinking
Let's continue reading run.go and check how the hooks are connected to the livelog hub and the store.
Tool
π§ read_file
{"end_line": 437, "path": "internal/agentrun/run.go", "start_line": 150}
Arguments
{"end_line": 437, "path": "internal/agentrun/run.go", "start_line": 150}
Result
{"path":"internal/agentrun/run.go","content":"\n\t\tif prInfo, err := r.forgejo.PullRequestInfo(ev.Owner, ev.Repo, ev.Index); err != nil {\n\t\t\tlogger.Warn(\"fetch pull request head failed; falling back to the event's head ref\", \"error\", err)\n\t\t} else if prInfo.HeadRef != \"\" {\n\t\t\theadRef = prInfo.HeadRef\n\t\t}\n\n\t\tif headRef == \"\" {\n\t\t\treturn fmt.Errorf(\"pr:review event has no pull request head branch to check out\")\n\t\t}\n\n\t\tbranch = headRef\n\n\t\t// Fetch the full review (verdict, body, inline comments) so the\n\t\t// agent sees all the feedback, not just the triggering event. A\n\t\t// failure degrades to no review detail rather than failing the\n\t\t// run: the agent can still do its job, just without the inline\n\t\t// comments.\n\t\treview, err = r.forgejo.ReviewDetail(ev.Owner, ev.Repo, ev.Index, ev.ReviewID)\n\t\tif err != nil {\n\t\t\tlogger.Warn(\"fetch review detail failed; agent will not see inline review comments\", \"error\", err)\n\t\t\treview = nil\n\t\t}\n\t}\n\n\troster := buildRoster(r.forgejo, r.cfg.Agents, logger)\n\tgitName, gitEmail := gitIdentity(agent.Name, roster)\n\n\t// The credential the sandbox's git uses for remote operations: the\n\t// agent's own Forgejo token when configured, so its git activity is\n\t// attributed to its own account, falling back to the shared zoo\n\t// identity for deployments without per-agent tokens (mirroring\n\t// forgejoAs).\n\tgitUser, gitToken := \"zoo\", r.forgejo.Token()\n\n\tif agent.Token != \"\" {\n\t\tgitUser, gitToken = agent.Name, agent.Token\n\t}\n\n\teventPath := filepath.Join(workDir, \"event.json\")\n\tif err := os.WriteFile(eventPath, ev.Raw, 0o644); err != nil {\n\t\treturn fmt.Errorf(\"write event file: %w\", err)\n\t}\n\n\tcontainerID, err := r.docker.createContainer(ctx, dockerImage, []string{\n\t\tprojectDir + \":/project\",\n\t\teventPath + \":/event:ro\",\n\t}, fmt.Sprintf(\"zoo-issue-%d-%s\", ev.Index, agent.Name))\n\tif err != nil {\n\t\treturn fmt.Errorf(\"start container: %w\", err)\n\t}\n\n\tdefer func() {\n\t\tcleanupCtx, cleanupCancel := context.WithTimeout(context.Background(), 30*time.Second)\n\t\tdefer cleanupCancel()\n\t\tif err := r.docker.remove(cleanupCtx, containerID); err != nil {\n\t\t\tlogger.Warn(\"failed to remove container\", \"container\", containerID, \"error\", err)\n\t\t}\n\t}()\n\n\t// Git must simply work inside the sandbox: safe.directory, commit\n\t// identity, and the remote credential all go into the container's\n\t// system gitconfig (see configureSandboxGit).\n\tif err := configureSandboxGit(ctx, r.docker, containerID, repoInfo.CloneURL, gitUser, gitToken, gitName, gitEmail); err != nil {\n\t\treturn fmt.Errorf(\"configure git in container: %w\", err)\n\t}\n\n\t// The initial clone happens inside the sandbox, so the working tree\n\t// is owned by the container's user and git never runs on the host.\n\tif ev.Kind == forgejo.EventPRReview {\n\t\tif err := clonePRHead(ctx, r.docker, containerID, repoInfo.CloneURL, repoInfo.DefaultBranch, branch, ev.Index); err != nil {\n\t\t\treturn fmt.Errorf(\"prepare git working tree: %w\", err)\n\t\t}\n\t} else {\n\t\tif err := cloneAndBranch(ctx, r.docker, containerID, repoInfo.CloneURL, repoInfo.DefaultBranch, branch); err != nil {\n\t\t\treturn fmt.Errorf(\"prepare git working tree: %w\", err)\n\t\t}\n\t}\n\n\tlogAppend := func(stream, line string) {\n\t\tif err := r.store.AppendLog(context.Background(), jobID, stream, line); err != nil {\n\t\t\tlogger.Warn(\"failed to append log\", \"error\", err)\n\t\t}\n\t}\n\n\trunCtx := \u0026runContext{\n\t\tdocker: r.docker,\n\t\tcontainerID: containerID,\n\t\tforgejo: \u0026runForgejoActions{\n\t\t\tclient: r.forgejoAs(agent.Name, agent.Token),\n\t\t\towner: ev.Owner,\n\t\t\trepo: ev.Repo,\n\t\t\tindex: ev.Index,\n\t\t\tlogger: logger,\n\t\t},\n\t}\n\n\tllmClient := llm.NewClient(llmCfg)\n\n\tsystemPrompt := defaultSystemPrompt + identitySection(agent.Name, roster)\n\n\tinstructions := r.cfg.EventInstructions(ev.Kind)\n\n\t// Fetch the full comment thread so the agent sees everything that's\n\t// been said on the issue/PR, not just the triggering event (which\n\t// only carries the latest comment, if any). A failure degrades to\n\t// no comments rather than failing the run: the agent can still do\n\t// its job, just without prior context.\n\tcomments, err := r.forgejo.ListIssueComments(ev.Owner, ev.Repo, ev.Index)\n\tif err != nil {\n\t\tlogger.Warn(\"fetch issue comments failed; agent will not see prior comments\", \"error\", err)\n\t\tcomments = nil\n\t}\n\n\tmessages := []llm.Message{\n\t\t{Role: \"system\", Content: systemPrompt},\n\t\t{Role: \"user\", Content: seedMessage(ev, branch, repoInfo.DefaultBranch, instructions, comments, review)},\n\t}\n\n\thooks := r.streamHooks(jobID, logAppend)\n\n\t_, err = runLoop(ctx, llmClient, runCtx, messages, hooks)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"agent loop: %w\", err)\n\t}\n\n\tsucceeded = true\n\n\treturn nil\n}\n\n// streamHooks builds the Hooks a single Run passes to runLoop: every\n// delta is published live to the hub for connected dashboard viewers,\n// and once a reasoning/content block or tool call is complete, it's\n// persisted to the store as one row and the hub's replay buffer for\n// jobID is checkpointed β so a viewer connecting from this point on\n// sees it via the persisted history instead of a live replay, and is\n// never shown it twice.\nfunc (r *Runner) streamHooks(jobID string, logAppend func(stream, line string)) Hooks {\n\tvar reasoningBuf, contentBuf strings.Builder\n\n\treasoningOpen, contentOpen := false, false\n\n\treturn Hooks{\n\t\tOnReasoningDelta: func(delta string) {\n\t\t\tif !reasoningOpen {\n\t\t\t\treasoningOpen = true\n\t\t\t\treasoningBuf.Reset()\n\t\t\t\tr.hub.Publish(jobID, livelog.Event{Type: livelog.ReasoningStart})\n\t\t\t}\n\n\t\t\treasoningBuf.WriteString(delta)\n\t\t\tr.hub.Publish(jobID, livelog.Event{Type: livelog.ReasoningDelta, Text: delta})\n\t\t},\n\t\tOnContentDelta: func(delta string) {\n\t\t\tif !contentOpen {\n\t\t\t\tcontentOpen = true\n\t\t\t\tcontentBuf.Reset()\n\t\t\t\tr.hub.Publish(jobID, livelog.Event{Type: livelog.ContentStart})\n\t\t\t}\n\n\t\t\tcontentBuf.WriteString(delta)\n\t\t\tr.hub.Publish(jobID, livelog.Event{Type: livelog.ContentDelta, Text: delta})\n\t\t},\n\t\tOnTurnEnd: func() {\n\t\t\tif reasoningOpen {\n\t\t\t\tr.hub.Publish(jobID, livelog.Event{Type: livelog.ReasoningEnd})\n\t\t\t\tlogAppend(\"reasoning\", reasoningBuf.String())\n\t\t\t\tr.hub.Checkpoint(jobID)\n\t\t\t\treasoningOpen = false\n\t\t\t}\n\n\t\t\tif contentOpen {\n\t\t\t\tr.hub.Publish(jobID, livelog.Event{Type: livelog.ContentEnd})\n\t\t\t\tlogAppend(\"content\", contentBuf.String())\n\t\t\t\tr.hub.Checkpoint(jobID)\n\t\t\t\tcontentOpen = false\n\t\t\t}\n\t\t},\n\t\tOnTool: func(name, arguments, result string, toolErr bool) {\n\t\t\tr.hub.Publish(jobID, livelog.Event{\n\t\t\t\tType: livelog.Tool,\n\t\t\t\tName: name,\n\t\t\t\tArguments: arguments,\n\t\t\t\tResult: result,\n\t\t\t\tError: toolErr,\n\t\t\t})\n\n\t\t\tline, err := json.Marshal(store.ToolLogEntry{Name: name, Arguments: arguments, Result: result, Error: toolErr})\n\t\t\tif err != nil {\n\t\t\t\tr.logger.Warn(\"failed to marshal tool log entry\", \"job\", jobID, \"error\", err)\n\t\t\t} else {\n\t\t\t\tlogAppend(\"tool\", string(line))\n\t\t\t}\n\n\t\t\tr.hub.Checkpoint(jobID)\n\t\t},\n\t}\n}\n\nfunc seedMessage(ev forgejo.Event, branch, defaultBranch, instructions string, comments []forgejo.IssueComment, review *forgejo.ReviewDetail) string {\n\traw, _ := json.MarshalIndent(json.RawMessage(ev.Raw), \"\", \" \")\n\n\tvar instructionsSection string\n\tif instructions != \"\" {\n\t\tinstructionsSection = fmt.Sprintf(\"Instructions for this event, from zoo.hcl:\\n%s\\n\\n\", instructions)\n\t}\n\n\t// A pr:review run works on the PR's own head branch, not a fresh\n\t// branch off the default branch.\n\tbranchLine := fmt.Sprintf(\"Your working branch is %q, checked out from the default branch %q.\\n\\n\", branch, defaultBranch)\n\tif ev.Kind == forgejo.EventPRReview {\n\t\tbranchLine = fmt.Sprintf(\"Your working branch is %q, the pull request's head branch β commits you push here update the pull request directly.\\n\\n\", branch)\n\t}\n\n\tvar reviewSection string\n\tif review != nil {\n\t\treviewSection = renderReviewSection(review)\n\t}\n\n\tvar commentsSection string\n\tif len(comments) \u003e 0 {\n\t\tvar b strings.Builder\n\t\tfmt.Fprintf(\u0026b, \"Comments (%d):\\n\\n\", len(comments))\n\n\t\tfor i, c := range comments {\n\t\t\tfmt.Fprintf(\u0026b, \"%d. %s (%s):\\n%s\\n\\n\", i+1, c.Author, c.Created.Format(time.RFC3339), c.Body)\n\t\t}\n\n\t\tcommentsSection = b.String()\n\t}\n\n\treturn fmt.Sprintf(\n\t\t\"You were triggered by a %q event on %s/%s.\\n\\n\"+\n\t\t\t\"%s%s\"+\n\t\t\t\"%sTitle: %s\\n\\nBody:\\n%s\\n\\n%sFull event payload:\\n```json\\n%s\\n```\",\n\t\tev.Kind, ev.Owner, ev.Repo, instructionsSection, branchLine, reviewSection, ev.Title, ev.Body, commentsSection, raw)\n}\n\n// renderReviewSection renders the submitted review as a briefing\n// section: the verdict, the review body, and each inline comment with\n// its location and id (the id lets the agent refer to a specific\n// comment in its reply).\nfunc renderReviewSection(review *forgejo.ReviewDetail) string {\n\tvar b strings.Builder\n\n\tfmt.Fprintf(\u0026b, \"Review submitted by %s:\\n\", review.Reviewer)\n\tfmt.Fprintf(\u0026b, \" Verdict: %s\\n\", humanReviewState(review.State))\n\n\tif review.Body != \"\" {\n\t\tb.WriteString(\" Review body:\\n\")\n\t\tfor _, line := range strings.Split(review.Body, \"\\n\") {\n\t\t\tfmt.Fprintf(\u0026b, \" %s\\n\", line)\n\t\t}\n\t}\n\n\tif len(review.Comments) \u003e 0 {\n\t\tfmt.Fprintf(\u0026b, \" Inline comments (%d):\\n\", len(review.Comments))\n\n\t\tfor i, c := range review.Comments {\n\t\t\twhere := c.Path\n\t\t\tif c.Line \u003e 0 {\n\t\t\t\twhere = fmt.Sprintf(\"%s:%d\", c.Path, c.Line)\n\t\t\t}\n\n\t\t\tfmt.Fprintf(\u0026b, \" %d. [%s] %s (comment id %d):\\n\", i+1, where, c.Author, c.ID)\n\t\t\tfor _, line := range strings.Split(c.Body, \"\\n\") {\n\t\t\t\tfmt.Fprintf(\u0026b, \" %s\\n\", line)\n\t\t\t}\n\t\t}\n\t}\n\n\treturn b.String() + \"\\n\"\n}\n\n// humanReviewState maps a Forgejo review state to a readable verdict.\nfunc humanReviewState(state string) string {\n\tswitch state {\n\tcase \"APPROVED\":\n\t\treturn \"approved\"\n\tcase \"REQUEST_CHANGES\":\n\t\treturn \"changes requested\"\n\tcase \"COMMENT\":\n\t\treturn \"comment\"\n\tdefault:\n\t\treturn state\n\t}\n}","start_line":150,"end_line":437,"total_lines":437,"truncated":false}
Thinking
Now I have a good grasp of the overall flow. Let me analyze the bug:
**Issue 1: Empty block-body**
In `streamHooks`:
- `OnReasoningDelta` fires when `msg.ReasoningContent` grows.
- `OnContentDelta` fires when `msg.Content` grows.
- `OnTurnEnd` persists the buffer and closes the block.
Now, when can a content block be empty?
Looking at `runLoop`:
```go
if hooks.OnContentDelta != nil && len(msg.Content) > len(prevContent) {
hooks.OnContentDelta(msg.Content[len(prevContent):])
}
prevContent = msg.Content
```
So a delta is only published when content has grown. `contentOpen` becomes true only when a content delta is received. `OnTurnEnd` persists only if `contentOpen`. So a persisted content block should always have at least one character... unless the delta is whitespace-only? No wait β if a delta is received, the buffer has content.
Hmm, wait, but what about the SSE client? Let me think about the "empty block-body" example:
```html
<div class="block block-content"><div class="block-body">
</div></div>
```
Note: this is inline, no indentation β this looks like it was created by JavaScript's `newBlock("content", null)`: `div.appendChild(body)` where body is empty. The static template renders with indentation. So the empty block was created by the live JS, and the block body remained empty.
How could that happen? The JS:
```js
case "content_start":
contentBody = newBlock("content", null);
break;
case "content_delta":
if (contentBody) contentBody.textContent += ev.text;
break;
case "content_end":
if (contentBody) contentBody.textContent = contentBody.textContent.trim();
contentBody = null;
break;
```
So if `content_start` is received but no `content_delta` arrives (or the delta text is empty), the block remains empty. Then `content_end` trims (no-op) and sets `contentBody = null`. The empty block stays in the DOM.
When can `content_start` be published without any `content_delta`? In `streamHooks`, `OnContentDelta` publishes `ContentStart` when the first delta arrives. So `ContentStart` and at least one `ContentDelta` are always paired...
Wait β but there's a race: `Hub.Publish` fans out to subscribers, and a subscriber whose channel is full misses the event (`select { case ch <- ev: default: }`). So if the browser tab is slow (e.g. the page is in a background tab and JS is throttled), a `content_delta` event could be dropped while `content_start` arrives. Then the block would be empty. Hmm, but that would also drop the start...
Actually, wait. Let me reconsider. There's another important scenario: **a turn with only tool calls and no content**. In that case, no content events are published at all. So no empty block.
What about a turn where the model emits content, then tool calls? `OnTurnEnd` persists content and checkpoints. No problem.
Hmm, let me think about the case where a message has both reasoning and content... no problem.
Let me look at the LLM streamer to understand how `msg.Content` is accumulated. Maybe the streamer sets `msg.Content` in a way that could cause a delta to be published with an empty string? `len(msg.Content) > len(prevContent)` β the delta is `msg.Content[len(prevContent):]`, which is non-empty. OK.
Wait, actually β let me re-read the issue:
"These are sometimes empty in the job log - I'm pretty sure there should be some text in there. Maybe just when streaming; maybe also when looking at old logs. I'm not sure."
So the empty block-body has "some text in there" β meaning the user thinks the text should be there. And the non-empty example has "way too much vertical space used":
```html
<div class="block block-content">
<div class="block-body">
Let me check the tools package (for testability of `runLoop`) and the existing integration test setup.
</div>
</div>
```
This is a static template rendering (with indentation). The block body has a leading newline and trailing newlines. Wait β but `buildBlocks` does `strings.TrimSpace(l.Line)` and skips empty blocks. So how does the static rendering have leading/trailing newlines?
Hmm, wait. The static template is:
```html
<div class="block block-content">
<div class="block-body">{{.Text}}</div>
</div>
```
`.Text` is trimmed, so there shouldn't be leading/trailing newlines. But the example shows a newline after `<div class="block-body">` and before `</div>`.
Hmm, wait β could this be an old log from before the trim fix? The recent commit b75b64d "Fix excessive vertical space in job view blocks (#53)" β let me see what that did. Actually, the issue says "Example of non-empty (but with way too much vertical space used)". So the user is seeing this on the current code? Or maybe the user saw it before the fix.
Wait, let me check the git history. Issue #60 was created 2026-08-26T12:15. The merge of #55 (fix for #53) is 98298f6. Let me check the dates.
Actually, let me check what commit b75b64d changed.
Actually, hold on. Let me reconsider. The empty block example:
```html
<div class="block block-content"><div class="block-body">
</div></div>
```
No indentation β this is JS-generated DOM (document.createElement doesn't add whitespace). The block body contains only a newline. Interesting β the body contains `\n`? If `textContent` were empty, the serialized HTML would be `<div class="block-body"></div>`. The example shows a newline inside. Hmm, but that might just be how the user copy-pasted it from the browser's "View Source" β no wait, "View Source" shows the original HTML, not the DOM. If the user used "View Source", they'd see the static HTML with indentation. The empty example has no indentation, so the user probably inspected the DOM (e.g. copied the element's outerHTML from devtools). In that case, the newline inside the empty block-body is... hmm, if textContent is "", outerHTML should be `<div class="block-body"></div>`.
Actually, the newline might be an artifact of the user's copy. Let's not over-interpret. The key point: the JS creates an empty content block.
So when does the JS create a content block with no text?
Scenario A: `content_start` is received, but the `content_delta` event is dropped because the subscriber's channel is full (slow tab). Then `content_end` arrives, trims the empty text, and the block stays empty.
Scenario B: The model streams content that is all whitespace (e.g. "\n\n"). In that case, the delta is published, the JS block gets "\n\n", and on `content_end` it trims to "" β empty block. And on the static side, `buildBlocks` skips whitespace-only blocks. So during streaming you see an empty block, and after reload the block disappears. This matches "I'm pretty sure there should be some text in there" β hmm, not really.
Wait, actually let me re-read: "These are sometimes empty in the job log - I'm pretty sure there should be some text in there."
Hmm, so the user sees an empty block where there should be text. That suggests text was lost, not that the model emitted whitespace.
Let me think about scenario A more carefully. When is the subscriber's channel full? `subChanBuffer = 256`. Events are small. A slow tab (background tabs throttle timers, but EventSource message handling... actually, does the browser throttle EventSource in background tabs? EventSource messages are delivered, but the tab's JS may be throttled. If the tab is throttled to 1/second and the model streams fast, the channel fills up and events are dropped.
But wait β there's a more subtle bug. Look at the SSE handler:
```go
buffered, ch, cancel := s.hub.Subscribe(id)
defer cancel()
write := func(ev livelog.Event) bool { ... }
for _, ev := range buffered {
if !write(ev) { return }
}
```
Let me look at `Subscribe` to check what `buffered` contains.
Let me read the rest of hub.go.
Tool
π§ read_file
{"end_line": 164, "path": "internal/livelog/hub.go", "start_line": 100}
Arguments
{"end_line": 164, "path": "internal/livelog/hub.go", "start_line": 100}
Result
{"path":"internal/livelog/hub.go","content":"func (h *Hub) Checkpoint(jobID string) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\ts.buf = nil\n}\n\n// Subscribe returns the events currently buffered for jobID (i.e. not\n// yet checkpointed) plus a channel of everything published from this\n// point on. The returned cancel func must be called when the caller is\n// done reading, to unregister and close the channel.\nfunc (h *Hub) Subscribe(jobID string) (buffered []Event, ch \u003c-chan Event, cancel func()) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\tbuffered = append([]Event(nil), s.buf...)\n\n\tc := make(chan Event, subChanBuffer)\n\ts.subs[c] = struct{}{}\n\n\tvar once sync.Once\n\n\tcancelFn := func() {\n\t\tonce.Do(func() {\n\t\t\ts.mu.Lock()\n\t\t\tdefer s.mu.Unlock()\n\n\t\t\tif _, ok := s.subs[c]; ok {\n\t\t\t\tdelete(s.subs, c)\n\t\t\t\tclose(c)\n\t\t\t}\n\t\t})\n\t}\n\n\treturn buffered, c, cancelFn\n}\n\n// Close publishes a terminal Status event, disconnects every current\n// subscriber, and drops jobID's state. Call this exactly once, when the\n// job's run has finished.\nfunc (h *Hub) Close(jobID string) {\n\th.Publish(jobID, Event{Type: Status, Status: \"done\"})\n\n\th.mu.Lock()\n\ts, ok := h.jobs[jobID]\n\tdelete(h.jobs, jobID)\n\th.mu.Unlock()\n\n\tif !ok {\n\t\treturn\n\t}\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\tfor ch := range s.subs {\n\t\tclose(ch)\n\t}\n\n\ts.subs = nil\n}","start_line":100,"end_line":164,"total_lines":164,"truncated":false}
Thinking
OK, let's understand the overall flow, and where the empty blocks come from.
Key insight: the SSE client's `es.onmessage` handles `content_start` by creating a new block. If the `content_delta` event gets dropped (slow subscriber), the block remains empty. But there's a more fundamental problem:
**The checkpoint/replay race.** Let me think:
1. Model streams content deltas β hub buffer accumulates `content_start`, `content_delta`ΓN.
2. `OnTurnEnd` β publishes `content_end`, persists the content line to the store, and checkpoints (clears the buffer).
3. A viewer connects after step 2 β sees the persisted block in the static HTML, and the SSE replay is empty. Good.
4. A viewer connects during step 1 β receives the buffered `content_start` + deltas, and then the `content_end` arrives live. Good.
Now, the JS side: `content_end` β trims the text. If the model's content was all whitespace, the block becomes empty (stays in the DOM). And on reload, `buildBlocks` skips whitespace-only blocks β the block disappears. This is the "empty block" case: **a whitespace-only content block** (e.g., the model emits "\n" or "\n\n" as a standalone content message β which actually happens! LLMs sometimes emit a newline-only content alongside tool calls, or a standalone "\n").
Actually, wait β let me reconsider the non-empty example:
```
Let me check the tools package (for testability of `runLoop`) and the existing integration test setup.
```
with a leading newline and two trailing newlines. If `buildBlocks` trims, this shouldn't appear in the static view. So this example must be from the **live JS view**? No wait β the JS trims on `content_end` too. Hmm.
But wait: the non-empty example has indentation:
```html
<div class="block block-content">
<div class="block-body">
Let me check the tools package...
```
8-space indentation on `<div class="block-body">` β the static template has 8 spaces of indentation on the block-body line (inside the `{{range .Blocks}}` loop with 6-space indentationβ¦ let me check: the template is:
```
<div class="log-container" id="log">
{{range .Blocks}}
{{if eq .Kind "reasoning"}}
<div class="block block-reasoning">
<div class="block-label">Thinking</div>
<div class="block-body">{{.Text}}</div>
</div>
{{else if eq .Kind "content"}}
<div class="block block-content">
<div class="block-body">{{.Text}}</div>
</div>
```
So `<div class="block-content">` has 6-space indentation, and `<div class="block-body">` has 8-space indentation. In the user's example, `<div class="block-content">` has 0 indentation and `<div class="block-body">` has 8-space indentation. Hmm, that doesn't match the static template exactly. In the user's example, `<div class="block-content">` is at column 0.
Hmm, wait, maybe the user copy-pasted from "View Source" and the formatting got mangled. Or maybe the example is from an older version of the template. Let me check the git history of the template to see what it looked like before.
Actually, let me check what commit b75b64d changed.
Tool
π§ bash
{"command": "cd /project && git show b75b64d --stat && git show b75b64d | head -200"}
Arguments
{"command": "cd /project && git show b75b64d --stat && git show b75b64d | head -200"}
Result
commit b75b64d1995a088c2c1427f8a6e965b449d14884
Author: Greg Coolio <greg@example.com>
Date: Tue Aug 25 21:44:52 2026 +0000
Fix excessive vertical space in job view blocks
Model reasoning/content output routinely starts/ends with newlines,
which white-space: pre-wrap in .block-body renders as visible blank
lines, inflating each block's height.
Trim leading/trailing whitespace for display in buildBlocks (internal
newlines are preserved; whitespace-only blocks are dropped entirely),
and trim the accumulated text in the live SSE view when a block ends
so it matches the static view. The stored log keeps the raw model
output; this is a display-layer fix, so existing jobs are covered too.
Fixes #53
internal/web/templates.go | 4 ++++
internal/web/web.go | 12 +++++++++++-
internal/web/web_test.go | 47 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 62 insertions(+), 1 deletion(-)
commit b75b64d1995a088c2c1427f8a6e965b449d14884
Author: Greg Coolio <greg@example.com>
Date: Tue Aug 25 21:44:52 2026 +0000
Fix excessive vertical space in job view blocks
Model reasoning/content output routinely starts/ends with newlines,
which white-space: pre-wrap in .block-body renders as visible blank
lines, inflating each block's height.
Trim leading/trailing whitespace for display in buildBlocks (internal
newlines are preserved; whitespace-only blocks are dropped entirely),
and trim the accumulated text in the live SSE view when a block ends
so it matches the static view. The stored log keeps the raw model
output; this is a display-layer fix, so existing jobs are covered too.
Fixes #53
diff --git a/internal/web/templates.go b/internal/web/templates.go
index dd63248..c64e61b 100644
--- a/internal/web/templates.go
+++ b/internal/web/templates.go
@@ -968,6 +968,9 @@ const templates = `
if (reasoningBody) reasoningBody.textContent += ev.text;
break;
case "reasoning_end":
+ // Model output routinely starts/ends with newlines; drop them
+ // so the finished block matches the static (trimmed) view.
+ if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();
reasoningBody = null;
break;
case "content_start":
@@ -977,6 +980,7 @@ const templates = `
if (contentBody) contentBody.textContent += ev.text;
break;
case "content_end":
+ if (contentBody) contentBody.textContent = contentBody.textContent.trim();
contentBody = null;
break;
case "tool":
diff --git a/internal/web/web.go b/internal/web/web.go
index eeec747..55ab97f 100644
--- a/internal/web/web.go
+++ b/internal/web/web.go
@@ -7,6 +7,7 @@ import (
"fmt"
"html/template"
"net/http"
+ "strings"
"sync"
"time"
@@ -210,7 +211,16 @@ func buildBlocks(logs []store.LogLine) []block {
for _, l := range logs {
switch l.Stream {
case "reasoning", "content":
- blocks = append(blocks, block{Kind: l.Stream, Text: l.Line})
+ // Model output routinely starts/ends with newlines. The block
+ // body renders with white-space: pre-wrap, so those would show
+ // up as visible blank lines inflating the block's height. Trim
+ // them for display (internal newlines are kept) and drop
+ // blocks that are nothing but whitespace.
+ text := strings.TrimSpace(l.Line)
+ if text == "" {
+ continue
+ }
+ blocks = append(blocks, block{Kind: l.Stream, Text: text})
case "tool":
var entry store.ToolLogEntry
diff --git a/internal/web/web_test.go b/internal/web/web_test.go
index 88974a8..ded09b2 100644
--- a/internal/web/web_test.go
+++ b/internal/web/web_test.go
@@ -104,6 +104,53 @@ func TestJobsAndDetail(t *testing.T) {
}
}
+// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content
+// blocks are rendered without the leading/trailing newlines the model
+// routinely emits: the block body uses white-space: pre-wrap, so those
+// would show up as visible blank lines inflating the block's height
+// (issue #53). Internal newlines must be preserved.
+func TestJobDetailTrimsBlockWhitespace(t *testing.T) {
+ s, st := testServer(t)
+ ctx := context.Background()
+
+ if err := st.CreateJob(ctx, store.Job{ID: "job-1", EventKind: "issue:new", Agent: "leon", Owner: "acme", Repo: "widgets", IssueIndex: 1}); err != nil {
+ t.Fatal(err)
+ }
+ if err := st.MarkJobFinished(ctx, "job-1", store.JobSucceeded, ""); err != nil {
+ t.Fatal(err)
+ }
+ if err := st.AppendLog(ctx, "job-1", "content", "\nNow the remaining tool callers:\n\n\n"); err != nil {
+ t.Fatal(err)
+ }
+ // A block that is nothing but whitespace should not render at all.
+ if err := st.AppendLog(ctx, "job-1", "content", " \n\t "); err != nil {
+ t.Fatal(err)
+ }
+ if err := st.AppendLog(ctx, "job-1", "reasoning", " \ninner\nlines\nkept\n "); err != nil {
+ t.Fatal(err)
+ }
+
+ r := httptest.NewRecorder()
+ s.Handler().ServeHTTP(r, httptest.NewRequest(http.MethodGet, "/jobs/job-1", nil))
+ if r.Code != http.StatusOK {
+ t.Fatalf("expected 200, got %d: %s", r.Code, r.Body.String())
+ }
+
+ body := r.Body.String()
+ if !strings.Contains(body, `<div class="block-body">Now the remaining tool callers:</div>`) {
+ t.Fatalf("expected trimmed content block, got: %s", body)
+ }
+ if strings.Contains(body, "<div class=\"block-body\">\n") {
+ t.Fatalf("block body still starts with a newline: %s", body)
+ }
+ if got := strings.Count(body, `class="block block-content"`); got != 1 {
+ t.Fatalf("expected exactly one content block (whitespace-only one dropped), got %d: %s", got, body)
+ }
+ if !strings.Contains(body, "inner\nlines\nkept") {
+ t.Fatalf("expected internal newlines to be preserved, got: %s", body)
+ }
+}
+
func TestAuthGate(t *testing.T) {
st, err := store.Open(filepath.Join(t.TempDir(), "zoo.db"))
if err != nil {
Thinking
So, the fix for #53 (excessive vertical whitespace) has already been merged. Issue #60 is a new issue, but the "non-empty example" in the issue body shows the old behavior (leading/trailing newlines) β the user probably grabbed that example before the #53 fix was deployed. The main complaint of this issue is the **empty block-body**.
Now, let me carefully analyze the empty block-body.
The empty example:
```html
<div class="block block-content"><div class="block-body">
</div></div>
```
No indentation β generated by JS (live view). The block body contains a newline (or is empty, and the user's copy-paste introduced a newline).
So, under what circumstances does the live JS create a `content` block that ends up empty?
Case 1: **Whitespace-only content from the model.** The model streams content that is only "\n" (or "\n\n"). The JS block accumulates "\n", and on `content_end` it gets trimmed to "" β an empty block remains in the DOM. On reload, `buildBlocks` discards whitespace-only blocks β the block disappears. So the user sees an empty block during streaming, and it vanishes on reload. "I'm pretty sure there should be some text in there" β hmm, in this case there's no text to begin with.
Case 2: **Dropped delta events.** The subscriber's channel is full β the `content_delta` event is dropped. The block is created on `content_start`, the delta is lost, and `content_end` trims the empty string β an empty block remains. On reload, the full text is displayed (because it was persisted). This matches "I'm pretty sure there should be some text in there" β the text exists in the persisted log, but the live view shows an empty block. And "maybe only during streaming" β yes, this is a streaming-only problem.
Hmm, but wait. There's a more subtle and more common variant of Case 2. Let me look at the SSE handler and the hub again.
Actually β wait. There's a bigger problem. Let me look at `handleJobEvents` again:
```go
buffered, ch, cancel := s.hub.Subscribe(id)
defer cancel()
```
And the JS:
```js
es.onmessage = function(e) { ... }
```
EventSource has a **reconnection** feature! If the SSE connection drops (e.g., the server restarts, network blip, or the handler returns), the browser automatically reconnects. On reconnection, `Subscribe` is called again, and the **buffered events are replayed**.
Now, here's the race: the `content_end` event is published, then `logAppend` persists, then `Checkpoint` clears the buffer. If the SSE connection drops between `content_end` and `Checkpoint`β¦ no wait, that's a tight sequence.
But here's a real race: **the `status` event and page reload.** When the job completes, `hub.Close(jobID)` publishes `Status{done}` and closes all subscriber channels. The JS receives `status` β `es.close(); location.reload()`. The reload fetches the static page with the persisted blocks. No problem.
But what if the reload happens before the final log line is persisted? Let me check the order in the scheduler: when is `hub.Close` called relative to `MarkJobFinished`? Let me look at scheduler.go.
Actually, let me think about the empty block from a different angle. Let me look at the JS again:
```js
case "content_start":
contentBody = newBlock("content", null);
break;
```
`newBlock` appends to `log`. If the page is reloaded mid-stream (manual refresh, or a previous `status` event), the new page re-subscribes and receives the buffered events. No problem.
But here's a subtle bug: **if a `content_start` arrives while a previous content block is still open** (i.e., `contentBody != null`), the JS overwrites `contentBody` with a new block, orphaning the previous block. When does this happen? In `streamHooks`, `contentOpen` is reset in `OnTurnEnd`. So a new `content_start` is only published after the previous block has been closed. However⦠if the `content_end` event was dropped (slow subscriber), the JS's `contentBody` is still non-null, and the next turn's `content_start` creates a new block and overwrites the reference. The old block remains in the DOM with its partial text (not empty, but cut off mid-way). And the next `content_end` trims the new block.
Hmm, interesting, but this produces a truncated block, not an empty block.
Let me focus. What's the most likely cause of an empty block-body that "should have some text in there"?
Let me re-read the issue:
"These are sometimes empty in the job log - I'm pretty sure there should be some text in there. Maybe just when streaming; maybe also when looking at old logs. I'm not sure."
So, the user is seeing an empty block in the job log. They're not sure whether it's only during streaming or also for old logs.
Now, let me think about what happens in the **static view** (old logs). `buildBlocks` discards whitespace-only blocks. So a whitespace-only persisted block doesn't render. A non-whitespace block renders with trimmed text. So the static view shouldn't show an empty blockβ¦
Wait. Let me actually look at the empty example again:
```html
<div class="block block-content"><div class="block-body">
</div></div>
```
There's a newline between `<div class="block-body">` and `</div>`. In the static template, the block-body line is `<div class="block-body">{{.Text}}</div>` β all on one line. If `.Text` is empty (which can't happen since buildBlocks discards empty ones), it would be `<div class="block-body"></div>` on one line. The user's example has a newline, so this is the DOM (JS-generated) β when you copy an element from devtools, the outerHTML of an empty div is `<div class="block-body"></div>`β¦ hmm, no newline.
Unless the textContent is "\n"! If the model streamed only "\n" and the JS trimmed on content_end⦠no, trim removes that.
Hmm, wait β what if the `content_end` event was dropped? Then `contentBody` is never trimmed, and the block retains the raw "\n" (whitespace-only content). outerHTML β `<div class="block-body">\n</div>`. That matches the user's example exactly!
So: the model emits a whitespace-only content message (e.g., "\n"), or the content_end is dropped.
But actually, hold on. Let me step back and think about what the model actually does. In this agent setup, the model typically:
1. Emits reasoning + content (like "Let me check the tools package...") + tool calls.
2. Emits more content + tool calls.
3. Finally emits a final content message.
The non-empty example in the issue: "Let me check the tools package (for testability of `runLoop`) and the existing integration test setup." β that's a typical intermediate content message with tool calls.
Now β when does the model emit a whitespace-only content? Actually, a known behavior of some LLMs (especially with reasoning models): when the model makes a tool call, it may emit an empty or whitespace-only `content` field. E.g., `content: "\n"` or `content: ""`.
In `runLoop`:
```go
if hooks.OnContentDelta != nil && len(msg.Content) > len(prevContent) {
hooks.OnContentDelta(msg.Content[len(prevContent):])
}
```
If the model emits content "\n" (one newline), a delta "\n" is published β `content_start` + `content_delta("\n")`. Then `OnTurnEnd` β `content_end`, persist "\n", checkpoint.
Live view: block created, "\n" appended, trimmed to "" on end β **empty block remains in the DOM**.
Static view: `buildBlocks` discards it β no block.
So during streaming, the user sees an empty content block where the model emitted a whitespace-only message. "I'm pretty sure there should be some text in there" β the user assumes the block should have text, but actually the model emitted whitespace. Hmm, but would the user say "there should be some text in there" about a whitespace-only model message? Maybe β they see an empty block and assume something went wrong.
But wait, there's another important scenario to check: **what if the model emits content in a message that also has tool calls, and the content is real text, but the `content_end`/trim logic has a bug?** No, the trim logic is fine.
Hmm, let me also consider: **what if the model emits content after a tool call in the same turn?** No β one turn = one completion. Content comes before tool calls in the same message. The next turn starts fresh.
OK, another thought β what about **the SSE replay on reconnection**? EventSource auto-reconnects. Scenario:
1. The page is open, streaming.
2. The connection drops (e.g., the server process restarts, or a network blip).
3. The browser reconnects after, say, 3 seconds.
4. In the meantime, the model has finished a content block: `content_end` was published, persisted, and checkpointed.
5. On reconnection, `Subscribe` returns the current buffer (which may contain the next turn's events). The JS has `contentBody = null` (the old page stateβ¦ no wait, the JS state is preserved across reconnection! EventSource reconnects transparently β the page's JS variables `reasoningBody`/`contentBody` are not reset!).
Here's the bug: **if the SSE connection drops mid-block and reconnects, the JS state gets out of sync.** E.g.:
1. Turn N: `content_start` received, `contentBody` = block A (in DOM).
2. Connection drops. Some `content_delta` events are lost (they were in flight / dropped).
3. `content_end` is published, content is persisted, checkpointed.
4. Connection reconnects. `Subscribe` replays the buffer: if the buffer has events from turn N+1 (e.g., a new `content_start` + deltas), the JS receives `content_start` β creates block B, overwrites `contentBody` (block A is orphaned with partial text). Then deltas go to B. Block A remains in the DOM with partial text (not empty, but cut off mid-way).
But if the buffer is empty on reconnection (everything checkpointed), the JS just waits. Block A remains with partial text, and `contentBody` still points to A. The next `content_start` (turn N+1) creates block B and overwrites. Block A is orphaned with partial text.
Hmm, so a dropped `content_end` (or a reconnection race) leaves a block with partial text, not an empty block.
For an empty block: `content_start` received, then all deltas lost, then `content_end` (or never). Block A is empty.
When are all deltas lost? If the subscriber's channel is full (256 events). The model streaming a long message produces many delta events. If the tab is slow (background tab throttling!), the channel fills up, and events are dropped β including `content_start`? No wait β if `content_start` is dropped, no block is created. If `content_start` arrives and subsequent deltas are dropped, the block is empty.
Hmm, but actually, there's a more deterministic scenario. Let me look at the hub's fanout again:
```go
for ch := range s.subs {
select {
case ch <- ev:
default:
}
}
```
Each event is either delivered or dropped per subscriber. So a slow subscriber misses random events. The browser's EventSource delivers messages to JS as fast as JS can handle them⦠actually, the browser buffers SSE messages internally (the EventSource spec has an internal queue). The TCP connection + browser buffer can absorb a lot. The 256 channel fills up only if the browser's read side is slow.
OK, so dropped events are possible but intermittent β consistent with "sometimes empty."
But let me look for a more deterministic bug. Let me re-examine the JS:
```js
var es = new EventSource("/jobs/" + jobID + "/events");
es.onmessage = function(e) { ... }
```
Note: the server writes `data: %s\n\n` β no `event:` field, so all messages go to `onmessage`. OK.
Now β **the `status` event**: `es.close(); location.reload()`. When the job completes, `hub.Close` publishes `Status{done}`. The JS reloads the page. The static page shows the persisted blocks.
But: what if the job completes and the reload happens, but the **last content block was persisted after the reload's page fetch**? Let me check the order in the scheduler.
Let me look at scheduler.go to see the order of operations when a job completes.
Now let me look at the scheduler to understand the job lifecycle and when `hub.Close` is called relative to persistence:
Tool
π§ read_file
{"end_line": 120, "path": "internal/scheduler/scheduler.go", "start_line": 1}
Arguments
{"end_line": 120, "path": "internal/scheduler/scheduler.go", "start_line": 1}
Result
{"path":"internal/scheduler/scheduler.go","content":"// Package scheduler resolves incoming Forgejo events to configured\n// agents and runs them, bounded by max_live_agents.\npackage scheduler\n\nimport (\n\t\"context\"\n\t\"errors\"\n\t\"fmt\"\n\t\"log/slog\"\n\t\"sync\"\n\n\t\"github.com/google/uuid\"\n\n\t\"github.com/abrander/zoo/internal/config\"\n\t\"github.com/abrander/zoo/internal/forgejo\"\n\t\"github.com/abrander/zoo/internal/livelog\"\n\t\"github.com/abrander/zoo/internal/store\"\n)\n\n// forgejoActions is the narrow slice of Client the scheduler needs for\n// its own failure-reporting side effects (defined here, not in\n// internal/forgejo, so tests can inject a fake).\ntype forgejoActions interface {\n\tCreateIssueComment(owner, repo string, index int64, body string) error\n\tAddLabel(owner, repo string, index int64, name string) error\n}\n\n// FailureLabel is applied to the triggering issue/PR, alongside a\n// comment, whenever an agent run fails or times out.\nconst FailureLabel = \"zoo:failed\"\n\n// Runner runs a single agent invocation to completion. Implemented by\n// internal/agentrun.Run; a narrow interface here so the scheduler is\n// testable without Docker.\ntype Runner interface {\n\tRun(ctx context.Context, jobID string, agent config.AgentConfig, llm config.LLM, dockerImage string, ev forgejo.Event) error\n}\n\ntype Scheduler struct {\n\tcfg *config.Config\n\tstore *store.Store\n\tforgejo forgejoActions\n\trunner Runner\n\thub *livelog.Hub\n\tlogger *slog.Logger\n\n\tsem chan struct{}\n\twg sync.WaitGroup\n}\n\nfunc New(cfg *config.Config, st *store.Store, fg forgejoActions, runner Runner, hub *livelog.Hub, logger *slog.Logger) *Scheduler {\n\treturn \u0026Scheduler{\n\t\tcfg: cfg,\n\t\tstore: st,\n\t\tforgejo: fg,\n\t\trunner: runner,\n\t\thub: hub,\n\t\tlogger: logger,\n\t\tsem: make(chan struct{}, cfg.Environment.MaxLive),\n\t}\n}\n\n// resolveAgent returns the name of the agent that should handle ev, if\n// any. Two kinds resolve dynamically: issue:assigned to the agent whose\n// config label matches the Forgejo assignee's username, and pr:review to\n// the agent whose config label matches the pull request author's\n// username (the agent that opened the PR reacts to the review of it).\n// Every other event kind uses the static event-\u003eagent mapping from\n// config.\nfunc resolveAgent(cfg *config.Config, ev forgejo.Event) (string, bool) {\n\tswitch ev.Kind {\n\tcase config.EventIssueAssigned:\n\t\tif _, ok := cfg.AgentByName(ev.Assignee); ok {\n\t\t\treturn ev.Assignee, true\n\t\t}\n\n\t\treturn \"\", false\n\n\tcase config.EventPRReview:\n\t\tif _, ok := cfg.AgentByName(ev.PRAuthor); ok {\n\t\t\treturn ev.PRAuthor, true\n\t\t}\n\n\t\treturn \"\", false\n\t}\n\n\treturn cfg.EventAgent(ev.Kind)\n}\n\n// Run consumes events until ctx is canceled or the channel closes,\n// dispatching each to its resolved agent and blocking on the\n// max_live_agents semaphore before starting a run.\nfunc (s *Scheduler) Run(ctx context.Context, events \u003c-chan forgejo.Event) {\n\tfor {\n\t\tselect {\n\t\tcase \u003c-ctx.Done():\n\t\t\treturn\n\n\t\tcase ev, ok := \u003c-events:\n\t\t\tif !ok {\n\t\t\t\treturn\n\t\t\t}\n\n\t\t\ts.handle(ctx, ev)\n\t\t}\n\t}\n}\n\nfunc (s *Scheduler) handle(ctx context.Context, ev forgejo.Event) {\n\tagentName, ok := resolveAgent(s.cfg, ev)\n\tif !ok {\n\t\ts.logger.Debug(\"no agent resolved for event, dropping\", \"kind\", ev.Kind, \"owner\", ev.Owner, \"repo\", ev.Repo, \"index\", ev.Index)\n\t\treturn\n\t}\n\n\t// An agent's own actions (e.g. a comment posted via the `comment`\n\t// tool, authenticated with its own per-agent token) can themselves\n\t// show up as new events. Don't let an agent trigger itself off its\n\t// own activity β that's a self-reinforcing loop, not new work.\n\tif ev.Author != \"\" \u0026\u0026 ev.Author == agentName {","start_line":1,"end_line":120,"total_lines":252,"truncated":true}
Thinking
Let me check the rest of scheduler.go, especially the part where the job is marked as complete and hub.Close is called.
Tool
π§ read_file
{"end_line": 252, "path": "internal/scheduler/scheduler.go", "start_line": 120}
Arguments
{"end_line": 252, "path": "internal/scheduler/scheduler.go", "start_line": 120}
Result
{"path":"internal/scheduler/scheduler.go","content":"\tif ev.Author != \"\" \u0026\u0026 ev.Author == agentName {\n\t\ts.logger.Debug(\"dropping event authored by the agent it would trigger\", \"kind\", ev.Kind, \"agent\", agentName, \"owner\", ev.Owner, \"repo\", ev.Repo, \"index\", ev.Index)\n\t\treturn\n\t}\n\n\tagent, ok := s.cfg.AgentByName(agentName)\n\tif !ok {\n\t\ts.logger.Error(\"resolved agent not declared in config\", \"agent\", agentName)\n\t\treturn\n\t}\n\n\tllm, ok := s.cfg.LLMByName(agent.LLM)\n\tif !ok {\n\t\ts.logger.Error(\"agent references undeclared llm\", \"agent\", agentName, \"llm\", agent.LLM)\n\t\treturn\n\t}\n\n\tjobID := uuid.NewString()\n\n\tif err := s.store.CreateJob(ctx, store.Job{\n\t\tID: jobID,\n\t\tEventKind: ev.Kind,\n\t\tAgent: agentName,\n\t\tOwner: ev.Owner,\n\t\tRepo: ev.Repo,\n\t\tIssueIndex: ev.Index,\n\t\tTitle: ev.Title,\n\t}); err != nil {\n\t\ts.logger.Error(\"failed to record job\", \"job\", jobID, \"error\", err)\n\t\treturn\n\t}\n\n\tselect {\n\tcase s.sem \u003c- struct{}{}:\n\n\tcase \u003c-ctx.Done():\n\t\treturn\n\t}\n\n\ts.wg.Add(1)\n\n\tgo func() {\n\t\tdefer s.wg.Done()\n\t\tdefer func() { \u003c-s.sem }()\n\n\t\ts.run(ctx, jobID, agent, llm, ev)\n\t}()\n}\n\nfunc (s *Scheduler) run(ctx context.Context, jobID string, agent config.AgentConfig, llm config.LLM, ev forgejo.Event) {\n\tlogger := s.logger.With(\"job\", jobID, \"agent\", agent.Name, \"event\", ev.Kind, \"owner\", ev.Owner, \"repo\", ev.Repo, \"index\", ev.Index)\n\n\t// Job status writes use a context detached from ctx, not ctx itself:\n\t// ctx is canceled on daemon shutdown to unwind the in-flight run, and\n\t// an already-canceled ctx would make these UPDATEs fail instantly,\n\t// leaving the job stuck at \"running\" forever even though the process\n\t// has exited.\n\tif err := s.store.MarkJobStarted(context.Background(), jobID); err != nil {\n\t\tlogger.Error(\"failed to mark job started\", \"error\", err)\n\t}\n\n\tlogger.Info(\"agent run starting\")\n\n\terr := s.runner.Run(ctx, jobID, agent, llm, s.cfg.Environment.DockerImage, ev)\n\n\tstatus := store.JobSucceeded\n\terrMsg := \"\"\n\n\tif err != nil {\n\t\terrMsg = err.Error()\n\t\t// The daemon-wide ctx passed in here isn't what times a run out\n\t\t// (agentrun.Runner.Run applies its own per-run deadline\n\t\t// internally); a timed-out run surfaces as a wrapped\n\t\t// context.DeadlineExceeded in the returned error instead.\n\t\tif errors.Is(err, context.DeadlineExceeded) {\n\t\t\tstatus = store.JobTimedOut\n\t\t} else {\n\t\t\tstatus = store.JobFailed\n\t\t}\n\n\t\tlogger.Error(\"agent run failed\", \"status\", status, \"error\", err)\n\t\ts.reportFailure(ev, status, err)\n\t} else {\n\t\tlogger.Info(\"agent run succeeded\")\n\t}\n\n\tif err := s.store.MarkJobFinished(context.Background(), jobID, status, errMsg); err != nil {\n\t\tlogger.Error(\"failed to mark job finished\", \"error\", err)\n\t}\n\n\t// Closing the hub here, only after the terminal status is durably\n\t// written, is what lets a dashboard tab's auto-reload (triggered by\n\t// this Close) see the finished status immediately. Closing it inside\n\t// Runner.Run instead β before this status write β raced a fast\n\t// reload against MarkJobFinished: the reloaded page could still see\n\t// \"running\", open a fresh SSE subscription against a hub entry that\n\t// no longer exists, and be stuck showing a stale status forever.\n\ts.hub.Close(jobID)\n}\n\n// reportFailure implements the locked-in failure policy: comment on the\n// triggering issue/PR with an error summary, and apply FailureLabel.\nfunc (s *Scheduler) reportFailure(ev forgejo.Event, status store.JobStatus, runErr error) {\n\tbody := fmt.Sprintf(\"zoo agent run %s: %s\", status, runErr.Error())\n\n\tif err := s.forgejo.CreateIssueComment(ev.Owner, ev.Repo, ev.Index, body); err != nil {\n\t\ts.logger.Error(\"failed to post failure comment\", \"owner\", ev.Owner, \"repo\", ev.Repo, \"index\", ev.Index, \"error\", err)\n\t}\n\n\tif err := s.forgejo.AddLabel(ev.Owner, ev.Repo, ev.Index, FailureLabel); err != nil {\n\t\ts.logger.Error(\"failed to add failure label\", \"owner\", ev.Owner, \"repo\", ev.Repo, \"index\", ev.Index, \"error\", err)\n\t}\n}\n\n// Shutdown stops accepting new work is the caller's responsibility (stop\n// feeding Run's channel); Shutdown just waits for in-flight runs, up to\n// ctx's deadline.\nfunc (s *Scheduler) Shutdown(ctx context.Context) error {\n\tdone := make(chan struct{})\n\n\tgo func() {\n\t\ts.wg.Wait()\n\t\tclose(done)\n\t}()\n\n\tselect {\n\tcase \u003c-done:\n\t\treturn nil\n\n\tcase \u003c-ctx.Done():\n\t\treturn ctx.Err()\n\t}\n}","start_line":120,"end_line":252,"total_lines":252,"truncated":false}
Thinking
OK, the scheduler looks fine. So let me carefully think through the empty-block scenarios again.
Let me trace through the whole pipeline once more, very carefully:
**Server side (streamHooks in run.go):**
- `OnReasoningDelta(delta)`: if not open β open, reset buffer, publish `ReasoningStart`. Append to buffer, publish `ReasoningDelta`.
- `OnContentDelta(delta)`: same for content.
- `OnTurnEnd()`: if reasoning is open β publish `ReasoningEnd`, persist, checkpoint, close. If content is open β publish `ContentEnd`, persist, checkpoint, close.
- `OnTool(...)`: publish `Tool`, persist, checkpoint.
**Client side (JS in templates.go):**
- `reasoning_start` β `reasoningBody = newBlock("reasoning", "Thinking")`.
- `reasoning_delta` β append.
- `reasoning_end` β trim, `reasoningBody = null`.
- `content_start` β `contentBody = newBlock("content", null)`.
- `content_delta` β append.
- `content_end` β trim, `contentBody = null`.
- `tool` β `newToolBlock(ev)`.
- `status` β close, reload.
**Scenarios that produce an empty content block in the live view:**
1. **Whitespace-only content from the model**: model emits content = "\n" (or " " etc.). Live: block created, "\n" appended, trimmed to "" on `content_end` β **empty block remains**. Static (after reload): `buildBlocks` drops it β no block. So the user sees an empty block during streaming. This is deterministic and matches "sometimes empty" (whenever the model emits whitespace-only content).
Actually, wait β is it common for models to emit whitespace-only content? Yes, actually! Especially with reasoning models (e.g., DeepSeek R1 style, or OpenAI o-series via proxies), when the model makes a tool call, the `content` field is often `""` or `"\n"`. Hmm, but if content is `""`, no delta is emitted (len 0 > len 0 is false), so no block is created. Only whitespace-only non-empty content ("\n") creates an empty block.
2. **Dropped events** (slow subscriber): `content_start` arrives but deltas are dropped β empty block. Or deltas arrive but `content_end` is dropped β block retains untrimmed text (leading/trailing newlines β matches the "way too much vertical space" example!).
Wait. Actually, let me look at the non-empty example again:
```html
<div class="block block-content">
<div class="block-body">
Let me check the tools package (for testability of `runLoop`) and the existing integration test setup.
</div>
</div>
```
The block body has a leading "\n" and trailing "\n\n". This is **untrimmed** text. In the current code, both the static view (buildBlocks trims) and the live view (JS trims on end) trim. So this example is from **before** the #53 fix (the issue was filed 2026-08-26 12:15, and the #53 fix was merged on 2026-08-25 21:44 β hmm, actually the fix was merged before the issue was filed).
Hmm, wait, let me check the dates:
- b75b64d (fix for #53): Tue Aug 25 21:44:52 2026 +0000
- Issue #60 filed: 2026-08-26T12:15:05+02:00 = 10:15 UTC on Aug 26.
So the #53 fix was merged about 13 hours before the issue was filed. But the user's example shows untrimmed text... Maybe the user's running instance hadn't been redeployed, or the user grabbed the example from an old page. Or...
Wait a moment. Let me reconsider. Maybe the user's example is from the live view where `content_end` was dropped (so no trim happened). If `content_end` is dropped, the block retains the raw text with leading/trailing newlines β "way too much vertical space". And if `content_start` arrives but all deltas are dropped β empty block.
Both examples can be explained by **dropped SSE events**! And "maybe just when streaming" β yes, both are streaming artifacts.
But wait, there's a problem with the "dropped events" theory for the non-empty example: the indentation. In the live JS view, `newBlock` creates `<div class="block block-content">` and appends the body div β no whitespace text nodes, no indentation. When you copy an element from devtools, you get `<div class="block block-content"><div class="block-body">...</div></div>` β no indentation. But the user's non-empty example has indentation:
```
<div class="block block-content">
<div class="block-body">
```
8-space indent on block-body. This matches the static template (8-space indent on the block-body line). And `<div class="block-content">` has no indent in the user's example, but 6-space in the template...
Hmm, well, the user probably copy-pasted from "View Source" (which shows the raw HTML with template indentation) and the formatting got mangled (e.g., pasted into an issue body, or trimmed). The empty example has no indentation at all, which is odd for "View Source"...
Actually, wait. Let me re-read the empty example:
```html
<div class="block block-content"><div class="block-body">
</div></div>
```
Hmm, if this is from "View Source" of the static page, the static template would render as:
```html
<div class="block block-content">
<div class="block-body">{{.Text}}</div>
</div>
```
with 6/8-space indentation. The user's example has no indentation. So it's not from "View Source" of the current template.
Unless... the empty block was created by JS (no indentation) and the user copied it from devtools (outerHTML). In that case, the newline inside block-body means textContent was "\n" β i.e., the block had untrimmed whitespace content. That happens when:
- The model emitted whitespace-only content AND `content_end` was dropped (no trim), or
- The user copied the block before `content_end` arrived (mid-stream, block has "\n" so far).
Hmm, OK. I'm going deep into speculation about how the user copy-pasted. Let me instead focus on what I can verify in the code and fix the actual defects:
**Defect 1 (deterministic): whitespace-only content/reasoning blocks render as empty blocks in the live view.**
The JS trims on `content_end`/`reasoning_end` but doesn't remove the block if the trimmed text is empty. The static view drops whitespace-only blocks entirely. So the live view shows an empty block that disappears on reload β inconsistent and confusing. Fix: on end, if the trimmed text is empty, remove the block from the DOM (to match the static view).
**Defect 2 (race): dropped SSE events desync the live view.**
If the subscriber's channel is full, events are silently dropped. This can produce:
- Empty blocks (start arrives, deltas dropped),
- Untrimmed blocks with extra vertical space (end dropped),
- Truncated blocks (mid-block deltas dropped),
- Orphaned blocks (start arrives while previous block still open because previous end was dropped).
This is a deeper problem. The hub's design deliberately drops events for slow subscribers ("a dropped event just means the subscriber's browser tab misses a chunk and catches up on the next one"). But "catches up on the next one" is wrong for block-based rendering: the next block starts fresh, and the missed chunk is never shown. The claim that "it catches up" only holds if the page reloads (which only happens on `status`).
Hmm, how to fix this properly? Options:
a) **Have the client detect desync and reload.** E.g., include a sequence number in each event; if the client detects a gap, reload the page (static view + new subscription). This is robust and simple.
b) **Don't drop events; block instead.** Change the fanout to block until the subscriber can receive (with a timeout). But then a dead/slow subscriber blocks the publisher (the agent loop!) β bad. The agent loop shouldn't be stalled by a slow browser.
c) **On the client, if a `*_start` arrives while the previous block of the same kind is still open, treat it as desync and reload.** This catches the "end was dropped" case. But it doesn't catch "deltas dropped mid-block" (block is truncated but looks fine).
d) **Sequence numbers**: each event gets a monotonically increasing seq per job (in the hub buffer). The client tracks the last seq; on gap β `location.reload()`. This is clean, catches all drop cases, and reload is cheap (static page + fresh subscription). The hub already has a replay buffer, so a reconnecting client gets the buffered events with seqs and can verify continuity.
Actually, wait β even with seqs, there's a subtlety with the replay buffer: when the client reconnects (EventSource auto-reconnect), it gets the current buffer. If the buffer was checkpointed (cleared) between the drop and the reconnect, the client can't verify continuity from the buffer alone... but if we include a seq in each event, the client can compare against the last seq it saw: if the first event of the new subscription has seq > lastSeq+1, there's a gap β reload. If the buffer is empty, the client has no way to know... hmm, unless the server sends a "resync" event on connect that carries the current seq. E.g., the server sends `data: {"type":"resync","seq":N}` first, and the client compares N with its lastSeq: if N > lastSeq+1 β gap β reload.
This is getting complex. Let me think about what's proportionate for this codebase.
Actually, let me reconsider. Is dropping events really the cause of the user's empty blocks? The user says "sometimes empty". Let me think about how often the 256-event buffer would overflow. Each LLM stream chunk is one event. A typical agent turn: reasoning (hundreds of chunks?) + content (tens of chunks). The browser's EventSource reads from the TCP socket as fast as the event loop allows. In a foreground tab, JS runs fast β the channel shouldn't fill. In a background tab, the browser throttles... actually, does the browser throttle network reads for EventSource in background tabs? The TCP receive buffer absorbs data; the browser's SSE parser processes messages when the event loop runs. Background tabs are throttled to ~1Hz for timers, but I think network events are still processed reasonably promptly (the throttling is for timers, not network). Hmm, actually, Chrome throttles background tabs' timers, but network activity continues. EventSource message events should still fire.
So in practice, drops are rare but possible (e.g., laptop sleep, network stall, heavy page load).
Hmm, wait, actually β let me reconsider. There might be a more common, deterministic cause for empty blocks that I'm missing. Let me re-examine the interaction between `hub.Close` and the JS reload.
Job finishes:
1. `runLoop` returns (final turn: content, no tool calls).
2. `OnTurnEnd` has already published `content_end` + persisted + checkpointed.
3. `Runner.Run` returns nil.
4. Scheduler: `MarkJobFinished`, then `hub.Close(jobID)` β publishes `Status{done}` and closes subscriber channels.
5. JS receives `status` β `es.close(); location.reload()`.
Static page after reload: shows all persisted blocks. Fine.
But what if the user's tab missed the `status` event (dropped)? Then the SSE connection stays open... `hub.Close` closed the channel β the server's `handleJobEvents` loop: `case ev, ok := <-ch: if !ok { return }` β the handler returns, the SSE stream ends. The browser's EventSource sees the connection close β **auto-reconnects**. New connection: `GetJob` β status is now `succeeded` (MarkJobFinished ran before Close) β `handleJobEvents` returns immediately with an empty 200 response (no SSE headers... actually, it returns before setting headers, so it's a plain 200 with an empty body). EventSource gets a 200 with non-SSE content-type β the connection is considered failed β keeps retrying with backoff forever. The page stays in "live" mode (job status in the header is still "running"? no wait β the header status was rendered statically as "running" at page load; it doesn't update without a reload).
Hmm, so in that case the page is stuck showing "running" with the live blocks β not an empty block. The user would notice the stuck status.
OK, one more thought β what about **the first turn**? Let me look at the JS again:
```js
case "reasoning_start":
reasoningBody = newBlock("reasoning", "Thinking");
break;
```
And the static template renders a reasoning block with a "Thinking" label. Fine.
Now, let me think about **a turn where the model emits content but no reasoning, followed by a turn with reasoning but no content** β the standard case. Fine.
**A turn where the model emits only reasoning and tool calls (no content)?** No content events. Fine.
Hmm, what about **`OnTurnEnd` firing when neither reasoning nor content was open**? Nothing happens. Fine.
OK, yet another angle: let me look at the LLM streamer and check how `msg.Content` is accumulated across chunks β maybe there's a bug where content gets reset or duplicated.
Let me look at the LLM streamer to understand how content deltas are accumulated:
Tool
π§ read_file
{"end_line": 120, "path": "internal/llm/streamer.go", "start_line": 1}
Arguments
{"end_line": 120, "path": "internal/llm/streamer.go", "start_line": 1}
Result
{"path":"internal/llm/streamer.go","content":"package llm\n\nimport (\n\t\"bufio\"\n\t\"bytes\"\n\t\"encoding/json\"\n\t\"fmt\"\n\t\"io\"\n\t\"net/http\"\n)\n\ntype Streamer struct {\n\tcompletion ChatCompletion\n\tresp *http.Response\n\tscanner *bufio.Scanner\n\teof bool\n}\n\nfunc NewStreamer(resp *http.Response) (*Streamer, error) {\n\tif resp.StatusCode != http.StatusOK {\n\t\tbody, _ := io.ReadAll(resp.Body)\n\t\tresp.Body.Close()\n\t\treturn nil, fmt.Errorf(\"status: %d: %s\", resp.StatusCode, body)\n\t}\n\n\treturn \u0026Streamer{\n\t\tresp: resp,\n\t\tscanner: bufio.NewScanner(resp.Body),\n\t}, nil\n}\n\n// Get returns the accumulated completion after merging in the next SSE\n// chunk. Callers should keep calling Get until it returns io.EOF.\nfunc (s *Streamer) Get() (*ChatCompletion, error) {\n\tif s.eof {\n\t\treturn nil, io.EOF\n\t}\n\n\tprefix := []byte(\"data: \")\n\n\tvar buf []byte\n\n\tfor s.scanner.Scan() {\n\t\tif err := s.scanner.Err(); err != nil {\n\t\t\treturn nil, err\n\t\t}\n\n\t\tbuf = bytes.TrimSpace(s.scanner.Bytes())\n\n\t\tif len(buf) == 0 {\n\t\t\tcontinue\n\t\t}\n\n\t\tif bytes.HasPrefix(buf, prefix) {\n\t\t\tbreak\n\t\t}\n\t}\n\n\tbuf = bytes.TrimPrefix(buf, prefix)\n\n\tif bytes.Equal(buf, []byte(\"[DONE]\")) {\n\t\ts.resp.Body.Close()\n\t\ts.eof = true\n\t\treturn nil, io.EOF\n\t}\n\n\tvar completion ChatCompletion\n\n\t// Unknown fields are tolerated on purpose: servers (e.g. newer\n\t// llama.cpp builds) may add fields we don't know about yet, and\n\t// failing on them would break compatibility.\n\tif err := json.Unmarshal(buf, \u0026completion); err != nil {\n\t\treturn nil, fmt.Errorf(\"decode completion chunk: %w: %s\", err, buf)\n\t}\n\n\ts.completion.Merge(\u0026completion)\n\n\treturn \u0026s.completion, nil\n}","start_line":1,"end_line":79,"total_lines":79,"truncated":false}
Thinking
Let's take a look at the Merge function in types.go.
Tool
π§ read_file
{"end_line": 120, "path": "internal/llm/types.go", "start_line": 1}
Arguments
{"end_line": 120, "path": "internal/llm/types.go", "start_line": 1}
Result
{"path":"internal/llm/types.go","content":"// Package llm is an OpenAI-compatible chat completions client with\n// streaming and tool-call support, ported from ../a's llamacpp package.\npackage llm\n\nimport \"fmt\"\n\ntype Message struct {\n\tContent string `json:\"content\"`\n\tRole string `json:\"role\"`\n\tReasoningContent string `json:\"reasoning_content,omitempty\"`\n\tToolCalls []ToolCall `json:\"tool_calls,omitempty\"`\n\tToolCallID string `json:\"tool_call_id,omitempty\"`\n\tName string `json:\"name,omitempty\"`\n}\n\nfunc (m *Message) String() string {\n\tstr := fmt.Sprintf(\"Role: %s, Content: %s ReasoningContent: %s\", m.Role, m.Content, m.ReasoningContent)\n\n\tfor _, call := range m.ToolCalls {\n\t\tstr += fmt.Sprintf(\"\\n ToolCall: %s\", call.String())\n\t}\n\n\treturn str\n}\n\n// Merge folds a streamed delta into the accumulated message.\nfunc (m *Message) Merge(next *Message) {\n\tm.Content += next.Content\n\n\tif next.Role != \"\" {\n\t\tm.Role = next.Role\n\t}\n\n\tm.ReasoningContent += next.ReasoningContent\n\n\tminLength := 0\n\tfor _, choice := range next.ToolCalls {\n\t\tif choice.Index+1 \u003e minLength {\n\t\t\tminLength = choice.Index + 1\n\t\t}\n\t}\n\n\tif len(m.ToolCalls) \u003c minLength {\n\t\tnewToolCalls := make([]ToolCall, minLength)\n\t\tcopy(newToolCalls, m.ToolCalls)\n\t\tm.ToolCalls = newToolCalls\n\t}\n\n\tfor _, nextChoice := range next.ToolCalls {\n\t\tm.ToolCalls[nextChoice.Index].Merge(\u0026nextChoice)\n\t}\n}\n\ntype FunctionCall struct {\n\tName string `json:\"name\"`\n\tArguments string `json:\"arguments\"`\n}\n\ntype ToolCall struct {\n\tType string `json:\"type\"`\n\tId string `json:\"id\"`\n\tIndex int `json:\"index\"`\n\tName string `json:\"name\"`\n\tFunctionCall FunctionCall `json:\"function\"`\n}\n\nfunc (t *ToolCall) String() string {\n\treturn fmt.Sprintf(\"Type: %s, Id: %s, Index: %d, Name: %s, FunctionCall: {Name: %s, Arguments: %s}\",\n\t\tt.Type, t.Id, t.Index, t.Name, t.FunctionCall.Name, t.FunctionCall.Arguments)\n}\n\nfunc (t *ToolCall) Merge(next *ToolCall) {\n\tif next.Type != \"\" {\n\t\tt.Type = next.Type\n\t}\n\n\tif next.Id != \"\" {\n\t\tt.Id = next.Id\n\t}\n\n\tif next.Name != \"\" {\n\t\tt.Name = next.Name\n\t}\n\n\tt.Index = next.Index\n\n\tif next.FunctionCall.Name != \"\" {\n\t\tt.FunctionCall.Name = next.FunctionCall.Name\n\t}\n\n\tt.FunctionCall.Arguments += next.FunctionCall.Arguments\n}\n\ntype Property struct {\n\tType string `json:\"type\"`\n\tDescription string `json:\"description,omitempty\"`\n\tEnum []string `json:\"enum,omitempty\"`\n\tItems *Property `json:\"items,omitempty\"`\n}\n\ntype Parameters struct {\n\tType string `json:\"type\"` // object\n\tProperties map[string]Property `json:\"properties,omitempty\"`\n\tRequired []string `json:\"required,omitempty\"`\n}\n\ntype Function struct {\n\tName string `json:\"name\"`\n\tDescription string `json:\"description,omitempty\"`\n\tParameters Parameters `json:\"parameters,omitempty\"`\n\tStrict bool `json:\"strict\"`\n}\n\ntype Tool struct {\n\tType string `json:\"type\"`\n\tFunction Function `json:\"function\"`\n}\n\nfunc NewTool(name, description string) Tool {\n\treturn Tool{","start_line":1,"end_line":120,"total_lines":267,"truncated":true}
Thinking
The streamer looks fine. Content is accumulated via `+=`.
OK, let me check the web tests to understand the test infrastructure, and then formulate a fix plan.
Let me also re-check the `block` CSS to understand the "excessive vertical space" issue in the non-empty example. Actually, the #53 fix addressed the padding issue on the display side. The non-empty example in issue #60 shows untrimmed text β that's from before the #53 fix (the user probably captured it from an old deployment, or the issue body was written before the fix was deployed).
Wait, actually, let me re-read the issue body once more:
"These are sometimes empty in the job log - I'm pretty sure there should be some text in there. Maybe just when streaming; maybe also when looking at old logs. I'm not sure.
Example of empty: [JS-generated, no indent]
Example of non-empty (but with way too much vertical space used): [template-style, with indent]"
Hmm, the non-empty example has leading/trailing newlines inside block-body. If this is from the current static view, buildBlocks should trim. So either:
1. The user's instance is running pre-#53-fix code (likely β the fix was merged ~13 hours before the issue was filed, and the user may not have redeployed).
2. Or this is from a live view where `content_end` was dropped (no trim).
Given that the #53 fix exists and is merged, the "excessive vertical space" part is probably already fixed (for the static view). The remaining bug is the empty block.
Now, let me pin down the empty block bug precisely. I'll enumerate all paths that can produce an empty `.block-body` inside a `.block-content`:
**Static view:** `buildBlocks` skips whitespace-only. Non-whitespace renders trimmed text. β Can't produce an empty block. β (verified by TestJobDetailTrimsBlockWhitespace)
**Live view:**
1. `content_start` β block created. Text accumulates via deltas. On `content_end` β trim.
- If final text is whitespace-only β **empty block remains in DOM**. (Model emitted whitespace-only content, e.g. "\n".)
- If `content_end` was dropped β block remains untrimmed (raw leading/trailing newlines β extra vertical space), and `contentBody` stays non-null β next `content_start` orphans this block and creates a new one.
- If some deltas were dropped β block has truncated text (or empty if all deltas dropped).
- If `content_start` was dropped β no block (text appears... no wait, if start is dropped, `contentBody` is null, deltas are ignored (`if (contentBody)`), and `content_end` is also ignored. The text is completely missing from the live view until reload.)
So the live view has multiple desync failure modes, all stemming from **dropped events** or **whitespace-only content**.
Now, what's the right fix? Let me think as an architect:
**Root cause 1: The hub silently drops events for slow subscribers, but the client's rendering is not resilient to gaps.** The hub's comment says "a dropped event just means the subscriber's browser tab misses a chunk and catches up on the next one, never a hang" β but that's wrong for block-based rendering: a missed `content_start`/`content_end` permanently desyncs the block state. The only "catch up" is a full page reload.
**Root cause 2: The live view doesn't match the static view for whitespace-only blocks** (static drops, live keeps an empty shell).
**Fix plan:**
1. **Client-side desync detection + auto-reload (robustness):** Add a per-job monotonically increasing sequence number to every hub event. The client tracks the last-seen seq. On gap detection (event.seq != lastSeq+1), or on receiving a `*_start` while a block of that kind is still open (which indicates a missed `*_end`), the client does `location.reload()` β the static view is the source of truth and is always complete.
Actually, a simpler and more robust approach: **server sends a "resync" marker on subscribe** carrying the current seq, and the client compares. Hmm, but that requires the client to persist lastSeq across EventSource reconnects β which it does (JS variable, same page).
Let me design this:
- Hub: add `seq uint64` per stream (per job). `Publish` assigns `ev.Seq = s.seq++`... but wait, `Subscribe`'s buffered replay also needs seqs β the events in the buffer already have seqs assigned at publish time. Good.
- `Event` struct: add `Seq uint64 \`json:"seq,omitempty"\``.
- Client: `var lastSeq = 0;` On each event: if `ev.seq` is present: if `lastSeq !== 0 && ev.seq !== lastSeq + 1` β desync β `es.close(); location.reload(); return;` otherwise `lastSeq = ev.seq`.
- On reconnect: the server replays the buffered events. If the buffer was checkpointed (cleared) since the client's last event, the first replayed event's seq will be greater than lastSeq+1 β gap β reload.
- If the buffer is empty on reconnect (everything checkpointed, nothing new): the client receives no events and can't detect the gap! Example: client was at seq 5 (mid-block, missed content_end at seq 6, buffer was checkpointed at seq 7). Reconnect β empty buffer β client sits with a stale open block. The next event (seq 8+) will trigger a gap detection β reload. But if the next turn takes a while, the user sees a stale open block in the meantime. Hmm.
To handle the "empty buffer on reconnect" case, the server should send a resync event on subscribe: `{"type":"resync","seq":N}` where N is the last published seq (or 0 if none). Client: on resync, if `lastSeq !== 0 && resync.seq > lastSeq` β gap β reload. If resync.seq === lastSeq β in sync. If resync.seq < lastSeq β the job's stream was reset (checkpoint... no wait, seq is monotonically increasing per job lifetime, so resync.seq < lastSeq can't happen unless the hub entry was deleted and recreated β which happens after hub.Close! After Close, `h.jobs[jobID]` is deleted. A new Subscribe creates a fresh stream with seq 0. But after Close, the job is finished, so handleJobEvents returns early (status check) and never subscribes. OK, so in practice resync.seq < lastSeq can't happen. But to be safe, treat it as a gap too... actually, if the hub entry was recreated, the job must have been re-run β impossible for the same jobID. Treat `resync.seq !== lastSeq` (when lastSeq != 0) as a gap.)
Wait, but there's a subtlety: the resync event itself β should it have a seq? No, it's a control message. The client handles it separately.
Hmm, wait. Actually, let me simplify. Is the resync event really needed? The gap case with an empty buffer: the client has an open block (missed end). The buffer is empty. The client waits. The next event (start of next block) will have seq > lastSeq+1 β gap β reload. So the stale block lingers until the next event. For a long tool call (e.g. a 30-second bash), the user sees a stale open block for 30 seconds. Not great, but not terrible. The resync event fixes this immediately. It's cheap to add. Let me add it.
Actually β hmm, wait. Let me reconsider. Is there a simpler, more holistic approach?
**Alternative: make the client fully stateless per block.** Instead of the server sending start/delta/end, send the accumulated text with each delta (not just the delta). Then the client can always render the current complete state, and dropped events are self-healing (the next event carries the full text). This is the classic "state, not delta" approach for SSE.
- `content_delta` event carries `text` = the full accumulated content so far (not just the new delta).
- Client: `contentBody.textContent = ev.text` (replace, not append).
- If a delta is dropped, the next delta carries the full text β self-heals.
- If `content_start` is dropped: the client has no block to write to... still broken. But: if the client receives a `content_delta` while `contentBody == null`, it can create the block itself! This makes the client fully self-healing for content/reasoning blocks:
- `content_delta` with `contentBody == null` β create block, set text.
- `content_end` β trim, remove if empty, null.
- Dropped start β first delta creates the block. β
- Dropped deltas β next delta carries full text. β
- Dropped end β next start... hmm, if end is dropped, `contentBody` is non-null, and the next turn's first delta arrives with full text for the new turn β the client would overwrite the old block's text with the new turn's text. The old block shows the new text (wrong), and there's no new block. Hmm. To handle this: include a "block id" (turn number) in the event. If `ev.blockId !== currentBlockId` β the previous block was implicitly ended β trim/remove the old block, create a new one.
This is getting complex. The seq approach is simpler and more uniform: any gap β reload. Reload is cheap and gives the correct static view.
**Decision: seq-based gap detection + resync on subscribe.** This is clean, uniform, and handles all drop cases. Plus the whitespace-only fix (remove empty block on end in JS, to match static).
Wait, actually, hold on. Let me reconsider the scope. The issue is "Empty block-body". The minimal fix for the reported symptom is:
1. **Whitespace-only content β empty block in live view**: on `content_end`/`reasoning_end`, if trimmed text is empty β remove the block from the DOM. This directly fixes the most likely cause of the empty block (deterministic, no race required).
2. **Dropped events β empty/truncated/untrimmed blocks**: seq + gap detection + reload. This fixes the race-based causes.
Both are worth doing. #1 is a small JS change. #2 is a moderate change to hub + JS.
Hmm, wait. Let me reconsider whether whitespace-only content is really what the user is seeing. "I'm pretty sure there should be some text in there" β the user believes the empty block should have had text. If the model emitted whitespace-only content, there's no text to show β the block shouldn't exist at all. The user's intuition "there should be some text in there" suggests they saw an empty block at a point where the model was emitting text. That's the dropped-events scenario (or the user is just guessing).
Actually, you know what? Let me look at this from yet another angle. Let me check if there's a scenario where the model emits real text but the live view shows an empty block, without any event drops.
Looking at the JS again...
```js
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
var shouldScroll = nearBottom();
switch (ev.type) {
case "reasoning_start":
reasoningBody = newBlock("reasoning", "Thinking");
break;
...
```
Hmm, `newBlock` appends to `log`. If `log` (the #log container) doesn't exist... it does.
What about **two EventSource connections**? If the user has two tabs open, each has its own ES. Independent. No problem.
What about **`location.reload()` firing while a block is open**? On `status`, the page reloads. The static view shows the persisted blocks. The last content block was persisted in OnTurnEnd before runLoop returned. So the static view is complete. β
What about **the job failing mid-turn**? runLoop returns an error (e.g. stream error). The open block (contentOpen=true, buffer partially filled) is never persisted, and `content_end` is never published! The JS block remains open (untrimmed, partial text). Then the scheduler marks the job failed, hub.Close β status event β reload. Static view: the partial block is not persisted (OnTurnEnd never ran for that turn) β the block vanishes on reload. So during streaming, the user sees a partial block, and after reload it's gone. Not an empty block, but a "text vanished" case. Hmm β should we persist the partial block on error? That's a separate improvement (log completeness on failure). The issue is about empty blocks, so let me note it but maybe not fix it... actually, hmm, wait:
If the model's stream errors out right after emitting a few whitespace-only deltas... the block would show "\n" (untrimmed, no end event) β looks empty! And after reload it's gone. Edge case of an edge case.
OK, here's my refined understanding of the bug and fix:
**Primary fix (deterministic, most likely the reported bug): whitespace-only blocks render as empty shells in the live view.**
- JS: on `content_end`/`reasoning_end`, after trim, if text is empty β `div.remove()` (remove the whole block), matching the static view's behavior of dropping whitespace-only blocks.
**Secondary fix (robustness against dropped events): seq-based desync detection.**
- Hub: per-job monotonically increasing seq assigned on Publish.
- Event: `Seq uint64` field.
- handleJobEvents: send a `resync` event on subscribe carrying the current seq.
- JS: track lastSeq. On gap β close + reload.
Hmm, wait. Actually, let me reconsider the secondary fix once more. Is it over-engineering? The hub's comment explicitly says drops are acceptable: "a dropped event just means the subscriber's browser tab misses a chunk and catches up on the next one, never a hang." The premise "catches up on the next one" is false for block rendering. So the comment documents a design flaw. The seq fix makes the system actually correct. I think it's the right call as a senior dev β the empty block is a symptom of silent event loss, and the only way to make the live view trustworthy is to detect loss and fall back to the static view (which is the source of truth).
Actually, wait, let me reconsider once more. Let me re-read the hub comment:
"subChanBuffer bounds how many events a slow subscriber can lag behind by before new events are dropped for it. Generous for a single-user local dashboard; a dropped event just means a subscriber's browser tab misses a chunk and catches up on the next one, never a hang."
"catches up on the next one" β I think the original intent was: the next page load (or the final reload on status) shows the persisted state. So the live view is best-effort, and the static view is the truth. The problem is: the user is looking at the live view, and the empty block is confusing and persists until reload. With seq detection, the tab self-heals immediately.
OK β decision: implement both fixes.
Now, let me also consider: should the **server** skip publishing whitespace-only blocks? I.e., in streamHooks, if the final content is whitespace-only, don't persist it, and don't publish content_start/end? Hmm β but the start/delta were already published during streaming. We could suppress persistence (the store currently keeps whitespace-only lines, and buildBlocks drops them on display β that's fine, the display layer handles it). Changing the persistence behavior would be a bigger semantic change. The display-layer fix (JS removes empty blocks) is sufficient and consistent.
But wait β there's a subtlety in the JS fix: if the model emits whitespace-only content, the live view will show: block appears (on start), "\n" accumulates (visible as a blank line in the block β the block grows in height!), and on end the block vanishes. Slightly flickery but correct. Alternatively, we could avoid creating the block until the first non-whitespace delta arrives... but that requires the JS to buffer deltas until it knows they're non-whitespace β more complex. Actually, simpler: on `content_delta`, if the block's current text is all whitespace and the accumulated text is also all whitespace, don't create/expand the block... no wait, we don't know if more text is coming. Hmm.
Actually, the simplest correct behavior: create the block on start (as now), append deltas, and on end trim + remove if empty. The flicker is acceptable (a blank block for a moment). Actually, hmm, wait β do we even need to create the block on `content_start`? What if we create it lazily on the first delta? Then whitespace-only content would never create a block at all (the delta is "\n" β hmm, that's a delta, so the block would be created with "\n"...).
OK, cleaner idea: **the JS only creates the block when it first sees non-whitespace text.** Buffer deltas until the first non-whitespace character arrives:
```js
case "content_start":
contentBody = null;
contentBuf = "";
break;
case "content_delta":
if (contentBody == null) {
contentBuf += ev.text;
if (contentBuf.trim() === "") return; // still whitespace, keep buffering
// first real text: create the block with everything so far
contentBody = newBlock("content", null);
contentBody.textContent = contentBuf;
} else {
contentBody.textContent += ev.text;
}
break;
case "content_end":
if (contentBody) {
contentBody.textContent = contentBody.textContent.trim();
if (contentBody.textContent === "") contentBody.parentElement.remove();
contentBody = null;
}
contentBuf = "";
break;
```
Hmm wait, but if contentBuf has leading whitespace and then real text: " \nHello" β create the block with " \nHello"? The static view would trim to "Hello". To match, trim on creation: `contentBody.textContent = contentBuf.trim()`? No wait β that would lose internal whitespace... no: if contentBuf = " \nHello", trim β "Hello". The static view renders "Hello". Match. But if contentBuf = " \nHello " and more deltas come (" world"), the block has "Hello" + " world" = "Hello world" β the static view would render "Hello world" (internal double space preserved, leading trimmed). Slight mismatch (lost the space before "Hello"? no wait: " \nHello" trimmed is "Hello", then " world" appended β "Hello world"; static: " \nHello world" trimmed β "Hello world". Mismatch: "Hello world" vs "Hello world" β lost the double space. Edge case of an edge case. Hmm.
Simpler: create the block with the untrimmed contentBuf (preserving leading whitespace), and rely on the trim at end. The block will show a blank line at the top during streaming (same as today), and get trimmed on end. If the content turns out to be whitespace-only, the block is removed on end. This preserves all the text exactly and matches the static view after end. The only "cost": a whitespace-only block is visible (as an empty shell) during streaming until end. That's exactly the current behavior for whitespace-only content β the block is visible during streaming.
Hmm, so the lazy-creation approach doesn't actually fix the "empty block visible during streaming" case for whitespace-only content β it just defers creation until non-whitespace arrives. For whitespace-only content, no block is ever created (the buffer stays whitespace, end removes nothing).
Wait, that's what I want! Let me redo this:
- `content_start`: reset state (contentBody=null, contentBuf="").
- `content_delta`: append to contentBuf. If contentBody is null and contentBuf has non-whitespace β create the block, set textContent = contentBuf (untrimmed, preserving leading whitespace for fidelity... or trimmed? Let me think).
- `content_end`: if contentBody exists β trim; if empty β remove block. contentBody=null. contentBuf="".
For whitespace-only content: no block is ever created. β (fixes the empty block)
For normal content: block is created on the first non-whitespace delta. If there's leading whitespace, the block initially shows it (a blank line at the top during streaming), and gets trimmed on end. Same as today for normal content. β
For dropped events: still broken (that's what the seq fix is for).
Now, about setting textContent on creation: use untrimmed contentBuf? If contentBuf = "\n\nLet me check...", the block shows two blank lines then text β same as today's behavior (today: block created on start, deltas append, same result). OK, use untrimmed. Actually, hmm, wait β today the block is created on start (before any text), so the user sees an empty block, then text appears. With lazy creation, the user sees nothing until the first non-whitespace delta. Slightly different timing, but better (no empty shell).
Hmm, but actually, wait. Let me reconsider: is it worth the complexity? The alternative minimal fix: keep block creation on start, and on end remove if empty. The empty shell is visible during streaming for whitespace-only content. How long does whitespace-only content stream? The model emits "\n" β probably one chunk, and the turn ends quickly (tool call follows). So the empty shell is visible for a moment. But the user's report shows a persistent empty block (they inspected it). If it were momentary, they probably wouldn't have reported it. So the empty block they saw was either (a) a whitespace-only block that persisted because `content_end` was dropped, or (b) a real-text block whose deltas were dropped, or (c) a whitespace-only block they caught during streaming.
With lazy creation + remove-if-empty on end + seq gap detection, all three are fixed:
- (a): if end is dropped β seq gap detected on next event β reload. β (Also, with lazy creation, a whitespace-only block that never gets end... the block is never created in the first place! Because no non-whitespace delta arrived. ββ)
- (b): seq gap β reload. β
- (c): no block created for whitespace-only. β
Lazy creation is strictly better. Let me go with it.
Same treatment for reasoning blocks.
Now, the seq mechanism. Let me design it concretely:
**hub.go:**
```go
type Event struct {
Type Type `json:"type"`
Seq uint64 `json:"seq,omitempty"`
...
}
type stream struct {
mu sync.Mutex
buf []Event
subs map[chan Event]struct{}
seq uint64
}
func (h *Hub) Publish(jobID string, ev Event) {
s := h.get(jobID)
s.mu.Lock()
defer s.mu.Unlock()
s.seq++
ev.Seq = s.seq
s.buf = append(s.buf, ev)
...
}
```
Wait, but `Close` calls `Publish` for the status event β that gets a seq too. Fine.
**Resync on subscribe:** the server needs to know the current seq when a subscriber connects. `Subscribe` returns the buffered events. The client can derive the "current seq" as: the seq of the last buffered event, or... hmm, if the buffer is empty, we need the stream's seq. Let me add a method or extend Subscribe's return:
Option A: `Subscribe` returns `(buffered []Event, currentSeq uint64, ch, cancel)`.
Option B: server sends a resync event `{"type":"resync","seq":N}` β the client treats it as a control message.
I prefer having the server send the resync as the first SSE message. It fits the SSE flow naturally (the client's onmessage handles it uniformly). But the Event struct is also used for persistence... no, the resync is only sent over SSE, not published to the hub. The server can write it directly:
```go
buffered, seq, cancel := s.hub.Subscribe(id)
defer cancel()
// Tell the client where we're at so it can detect gaps (dropped
// events) and reload if the live view has fallen out of sync.
write(livelog.Event{Type: livelog.Resync, Seq: seq}) // hmm, but Resync isn't a real event type...
```
Hmm, adding a `Resync` Type to livelog is a bit awkward since it's not published via Publish (which assigns a seq). Let me think...
Actually, cleaner: have the SSE handler send a special first message. But the client's `onmessage` parses JSON and switches on type. We can add a `"resync"` type that the client handles:
```js
case "resync":
// Server tells us the latest seq it has. If we've seen events
// since our last one, we missed some β reload.
if (lastSeq !== 0 && ev.seq > lastSeq) { es.close(); location.reload(); return; }
break;
```
Wait, but note: the resync is sent on every (re)connect. On the first connect, lastSeq=0 β no-op. On reconnect after a gap: resync.seq > lastSeq β reload. On reconnect with no gap (buffer still has events with contiguous seqs): resync.seq == lastSeq β continue, and the replayed events follow with lastSeq+1... β.
Hmm wait, but there's a subtlety: on reconnect, the buffered events are replayed. If the buffer wasn't checkpointed, the first replayed event has seq = lastSeq+1 (contiguous) β but we already sent resync with seq = lastSeq (the current seq at subscribe time, which might be greater than lastSeq if new events arrived between subscribe and... no wait, Subscribe takes the lock, copies the buffer, and records the seq atomically. Events published after Subscribe have seq > the recorded seq and arrive via the channel. So: resync.seq = max seq at subscribe time. Replayed events: seqs 1..resync.seq (the ones in the buffer). New events: resync.seq+1, ...
Client on reconnect: lastSeq = L (last seen before drop).
- If buffer is empty and no new events: resync.seq = S (S β₯ L). If S > L β gap β reload. β (this is the "empty buffer" case I was worried about!)
- If buffer has events: resync.seq = S. If S > L β gap β reload. β (even if the buffer contains the missing events! Wait β can the buffer contain the missing events? If the client dropped events from the channel (channel full), those events are still in the hub's buffer (the buffer is independent of the channel). So on reconnect, the buffer replays them β the client could catch up without a reload! But the client can't easily verify that the replay is contiguous with what it saw... actually, it can: the replayed events have seqs. If the first replayed event's seq β€ L (i.e., the buffer contains events the client already saw or missed), the client can... hmm, this gets complex: the client would need to dedupe (skip events with seq β€ L) and detect gaps (a jump in the replay).
Hmm, OK, let me simplify the client logic:
```js
function handleSeq(ev) {
if (typeof ev.seq !== "number") return true;
if (lastSeq === 0) { lastSeq = ev.seq; return true; }
if (ev.seq === lastSeq + 1) { lastSeq = ev.seq; return true; }
// Gap (or duplicate/replay) β live view is out of sync.
return false;
}
```
Wait, but on reconnect with a buffer that replays old events (seq β€ lastSeq), `ev.seq === lastSeq + 1` fails (ev.seq < lastSeq) β we'd reload unnecessarily, even though the replay would have caught us up. Hmm. But is that bad? Reloading gives the correct static view + fresh subscription. It's a safe fallback. The only cost: an unnecessary reload when the buffer could have healed us.
Hmm, actually, wait. Let me reconsider: can the client's channel drop events that are still in the buffer? Yes β the buffer holds up to 10000 events (cleared on checkpoint), and the channel holds 256. If the browser is slow, the channel fills, events are dropped from the channel, but remain in the buffer. On reconnect, the buffer replays from the beginning (all buffered events, including ones the client already received). So a naive "expect lastSeq+1" check would fail on the first replayed event (which has a seq much smaller than lastSeq) β reload.
So the client logic should be: on a (re)connect, the first event after resync can be a replay. Let me handle it explicitly:
Actually, you know what β let me step back and simplify the whole thing.
**Simplest robust design:**
The client doesn't try to be clever about replays. Rules:
1. Every event carries a seq (monotonic per job).
2. Client tracks `lastSeq`.
3. On receiving an event with seq:
- If `lastSeq === 0` (first event ever): accept, set lastSeq.
- If `ev.seq === lastSeq + 1`: accept, lastSeq = ev.seq.
- Otherwise (gap or replay/duplicate): **reload the page** (close ES first).
4. Server sends `resync` (with current seq, no seq of its own... or with seq = current) as the first message on (re)connect. Client: if `lastSeq !== 0 && resync.seq > lastSeq` β reload (we missed events that are no longer in the buffer). If `resync.seq <= lastSeq`... hmm, resync.seq < lastSeq can't happen (monotonic, same job). resync.seq == lastSeq β we're in sync, and the buffer (if any) contains only events β€ lastSeq β the replay would be duplicates β rule 3 would reload on the first replayed event. Bad.
Ugh, the replay duplication problem. OK, let me handle it: the client should skip replayed events (seq β€ lastSeq) and only reload on a true gap (seq > lastSeq + 1) or a resync indicating a gap.
```js
function onEvent(ev) {
if (ev.type === "resync") {
if (lastSeq !== 0 && ev.seq > lastSeq) { resyncGap(); }
return;
}
if (typeof ev.seq !== "number") return; // shouldn't happen
if (lastSeq === 0) {
// First event (fresh page): accept whatever seq it has.
// (We might be joining mid-stream via a replay buffer.)
lastSeq = ev.seq;
} else if (ev.seq <= lastSeq) {
// Replay of an event we already processed (reconnect with a
// non-checkpointed buffer): skip.
return;
} else if (ev.seq === lastSeq + 1) {
lastSeq = ev.seq;
} else {
// Gap: we missed events. Reload to resync with the static view.
resyncGap();
return;
}
render(ev);
}
```
Wait, but there's still a hole: a fresh page (lastSeq=0) joining mid-stream via the replay buffer. The buffer contains events from the current (uncheckpointed) block: e.g. [content_start(seq 100), content_delta(101), ...]. The client accepts seq 100 as "first" and renders the block. β Good β that's the intended replay behavior.
But what if the buffer is [content_delta(101), content_delta(102)] β i.e., content_start(100) was checkpointed... no wait, the checkpoint clears the entire buffer. The buffer is always a suffix of the seq stream since the last checkpoint. Can the buffer start mid-block? Checkpoint happens on block end (OnTurnEnd/OnTool). So the buffer boundary is always at a block boundary... except: the buffer contains [content_start(100), delta(101), delta(102)], and the client connects, receives the replay, and then... the client is in sync from 100. No problem.
Hmm, but here's the thing: a fresh page's static HTML already contains all checkpointed blocks. The buffer only has uncheckpointed (current) events. So a fresh page + buffer replay = complete view. β And lastSeq=0 β accept the first replayed event at any seq. β
Now, the gap case for a fresh page: can a fresh page have a gap? It receives the buffer (contiguous from the last checkpoint) and then live events (contiguous after). No gap possible. β (Unless the hub's buffer was truncated by maxBufferedEvents β 10000 events β in which case the buffer starts mid-block! E.g., buffer = [delta(9998), delta(9999), delta(10000)] with the start at 9995 truncated. A fresh page would render a block starting mid-text. The lazy-creation JS would create the block on the first non-whitespace delta β the block would show partial text. Rare (10k events β a huge turn), acceptable. Actually, hmm, with lazy creation, the block is created on the first non-whitespace delta in the replay β the text is partial but looks fine. On end, it's trimmed. The user sees a truncated block. Edge case, acceptable β the alternative (detecting it) would require knowing the block's start seq, which we don't track. Fine.)
Now, the resync event: is it needed given the above? The gap case: the client was at lastSeq=L, missed events L+1..M (channel full), the buffer was checkpointed (cleared) at M, and new events M+1.. arrive. Without resync: the client receives M+1 β gap (M+1 > L+1) β reload. β So the gap is detected on the next event. The only case resync helps: if no further events come (the job is idle β e.g., a long tool call, or the job finished). If the job finished: hub.Close β status event β the client receives status (seq M+1 > L+1 β gap β reload) β wait, the status event has a seq (published via Publish). So the client reloads via the gap path. β If the job is idle (long tool call): the client sits with a stale open block until the next event. Resync on reconnect would catch this immediately β but the client only reconnects if the connection dropped. If the connection is alive and events are being dropped from the channel, the client doesn't know it's behind until the next event arrives. Resync only helps on (re)connect.
Hmm, OK, so resync helps in this case: the connection dropped (network blip), the client auto-reconnects, the buffer was checkpointed in the meantime, and the client was mid-block. Without resync: the client reconnects, receives no events (empty buffer), sits with a stale open block until the next turn's events arrive (could be minutes during a long tool call). With resync: the client immediately detects the gap and reloads.
Is this case worth the extra complexity? It's exactly the "connection dropped mid-block" case, which is the most likely real-world drop scenario (network blip, laptop sleep). And the fix is small: the server sends one extra SSE message on subscribe, and the client has one extra case. Let me include it.
Actually, hmm, wait. Let me reconsider the design once more. Instead of a separate `resync` message type, what if Subscribe returned the current seq and the server... no, the server has to communicate it to the client somehow. A message is the natural way. OK.
Let me also double-check: `handleJobEvents` β the resync must be sent before the buffered events, and the client must process it first. SSE messages are ordered. β
One more consideration: the `status` event triggers `es.close(); location.reload()`. With seq, the status event also goes through the seq check β if the client missed events before status, the gap check fires first β reload (same outcome). β
Now β where to put the seq check? In the JS, before the render switch. Let me write it:
```js
var lastSeq = 0;
function outOfSync() {
es.close();
location.reload();
}
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
if (ev.type === "resync") {
// Sent on (re)connect: the hub's latest seq. If we've seen
// events since our last one, we missed some that are no longer
// replayable β resync with the static view.
if (lastSeq !== 0 && ev.seq > lastSeq) outOfSync();
return;
}
if (typeof ev.seq === "number") {
if (lastSeq === 0) {
lastSeq = ev.seq; // joining mid-stream (fresh page or replay)
} else if (ev.seq <= lastSeq) {
return; // replayed event we already processed
} else if (ev.seq === lastSeq + 1) {
lastSeq = ev.seq;
} else {
outOfSync(); // gap: dropped events
return;
}
}
var shouldScroll = nearBottom();
switch (ev.type) { ... }
};
```
Hmm wait, one issue: `lastSeq === 0` β "first event ever". But what if the first event is a replay of an old block (buffer not checkpointed)? A fresh page's static HTML doesn't include that block (uncheckpointed), so rendering it is correct. β
But what about this: a fresh page, the buffer is empty, and the first event is content_delta (seq 500) because content_start (seq 499) was... no wait, the buffer is empty means everything was checkpointed, so the first live event is a new block's start. A fresh page can't miss events (it just subscribed; the channel starts empty and receives everything from then on, plus the buffer replay). The only way a fresh page sees a delta without a start: buffer truncation at maxBufferedEvents (10k) β the edge case discussed. With lazy creation, the block is created on the first non-whitespace delta. OK.
Now, the lazy-creation JS for content/reasoning:
```js
var reasoningBody = null, reasoningBuf = "";
var contentBody = null, contentBuf = "";
function openBlock(kind, label, buf) {
var body = newBlock(kind, label);
body.textContent = buf;
return body;
}
case "reasoning_start":
reasoningBody = null;
reasoningBuf = "";
break;
case "reasoning_delta":
reasoningBuf += ev.text;
if (!reasoningBody) {
if (reasoningBuf.trim() === "") break; // whitespace so far; wait for real text
reasoningBody = openBlock("reasoning", "Thinking", reasoningBuf);
} else {
reasoningBody.textContent += ev.text;
}
break;
case "reasoning_end":
if (reasoningBody) {
reasoningBody.textContent = reasoningBody.textContent.trim();
if (reasoningBody.textContent === "") reasoningBody.parentElement.remove();
reasoningBody = null;
}
reasoningBuf = "";
break;
```
Hmm wait, there's a subtlety with the lazy creation + append: when the block is created with `reasoningBuf` (which may have leading whitespace), subsequent deltas are appended with `textContent += ev.text`. The full text = the complete accumulated text. β On end: trim. β Matches the static view. β
But hmm, one inefficiency: `reasoningBuf += ev.text` builds the full string on every delta even after the block is created (O(nΒ²) over the whole block). For a long block (10k chars), that's 10k string concatenations of growing size β JS handles this reasonably (modern engines use rope-like strings), but it's wasteful. Alternative: only keep the buffer until the block is created:
```js
case "reasoning_delta":
if (reasoningBody) {
reasoningBody.textContent += ev.text;
} else {
reasoningBuf += ev.text;
if (reasoningBuf.trim() !== "") {
reasoningBody = openBlock("reasoning", "Thinking", reasoningBuf);
reasoningBuf = "";
}
}
break;
```
This is better: the buffer is only used while waiting for the first non-whitespace. Once the block is created, deltas go straight to the DOM. β
Wait, but `reasoningBuf.trim() !== ""` on every delta while waiting β that's fine (only while waiting, and the buffer is small until the first real text).
Hmm, actually, do we even need the buffer? What if we create the block immediately on the first delta (regardless of whitespace) and remove it on end if empty? Then:
- Whitespace-only content: the block is created (empty shell visible during streaming), removed on end. The empty shell is visible during streaming β exactly what the user complained about!
So no β lazy creation (waiting for non-whitespace) is the right call to avoid the empty shell entirely.
Hmm, wait, but hold on: with lazy creation, is there still a case where an empty block is visible during streaming? The block is created only when the buffer has non-whitespace. So the block always has some non-whitespace text at creation. During streaming, the text only grows. On end, it's trimmed (non-whitespace remains, since the text has non-whitespace... wait, can the text become whitespace-only after having non-whitespace? No β text only grows. If it had non-whitespace, it still has it). So on end, the trimmed text is never empty β the `remove()` on end is actually unreachable...
Wait, is that right? The block is created when buf has non-whitespace. Subsequent appends only add text. So the final text has non-whitespace. Trim β non-empty. So the block is never removed on end. The remove-if-empty on end is dead code... except in the desync case (e.g., the block was created, and then... no, text only grows).
Hmm, OK, so with lazy creation, the empty block on end can't happen. The remove-on-end is a just-in-case safety net. Let me keep it (cheap, defensive) β actually, hmm, let me keep it simple: since it's provably non-empty, maybe skip the remove... no wait, let me keep it. Defensive coding against future JS changes, and it documents the invariant (a block must never be empty). Actually β you know what, let me keep it. It's 2 lines.
Hmm, wait, actually, let me reconsider once more whether lazy creation breaks the "Thinking" label UX. Today: on reasoning_start, a "Thinking" block appears immediately (empty), and text streams in. With lazy: nothing appears until the first non-whitespace reasoning delta. For reasoning models, the first delta is usually non-whitespace (reasoning starts with text). The delay is negligible (a few ms). And for the common case of a turn with no reasoning (tool-only turn), nothing appears β same as today. OK, good.
Now, the server-side changes:
**hub.go:**
1. `Event.Seq uint64 \`json:"seq,omitempty"\``.
2. `stream.seq uint64`.
3. `Publish`: assign seq under the lock.
4. `Subscribe`: also return the current seq (after copying the buffer, under the same lock).
5. Add a `Resync` type? The resync message is written by the server, not published. But it goes through the same `write` function that marshals a `livelog.Event`. We can construct `livelog.Event{Type: "resync", Seq: seq}`... but `Type` is a typed string. Adding a `Resync Type = "resync"` constant is clean. It's not published via Publish (which would assign a seq and buffer it) β the server writes it directly to the SSE stream. Hmm, is that OK? The `write` closure just marshals and writes. Let me look at handleJobEvents:
```go
buffered, ch, cancel := s.hub.Subscribe(id)
defer cancel()
write := func(ev livelog.Event) bool { ... }
for _, ev := range buffered {
if !write(ev) { return }
}
```
Change to:
```go
buffered, seq, ch, cancel := s.hub.Subscribe(id)
defer cancel()
write := func(ev livelog.Event) bool { ... }
// Tell the client the hub's latest seq so it can detect a gap between
// what it last rendered and what we're about to replay (e.g., after a
// dropped connection): a gap means the live view is out of sync and
// must fall back to the static page.
if !write(livelog.Event{Type: livelog.Resync, Seq: seq}) {
return
}
for _, ev := range buffered { ... }
```
Wait, but the resync's `Seq` field: `json:"seq,omitempty"` β seq=0 is omitted. A new job (no events yet) β resync with no seq β the client's `ev.seq` is undefined β the client's resync handler: `if (lastSeq !== 0 && ev.seq > lastSeq)` β undefined > lastSeq is false β no reload. β Good.
Hmm, but wait: there's an ordering subtlety. `Subscribe` returns the seq at subscribe time. Then we write the resync, then the buffered events. Events published between Subscribe and the resync write go to the channel (the client is subscribed) and arrive after the buffered events (channel order). Their seq > the resync's seq. The client: resync (seq S), then buffered (β€ S), then live (> S). The client's seq logic: first buffered event β if lastSeq==0 (fresh page) β accept at any seq...
Wait. Problem: a fresh page (lastSeq=0) receives: resync(seq=S), buffered[0](seq=B0 β€ S), ... The client's resync handler: lastSeq==0 β no-op. Then buffered[0]: lastSeq==0 β lastSeq=B0, render. Then buffered[1]: B1 == B0+1 β β... contiguous through the buffer, then live events continue. β No problem.
A reconnecting page (lastSeq=L): resync(seq=S). If S > L β gap β reload. β If S == L β in sync. The buffer contains events β€ L (replays) β the client skips them (ev.seq <= lastSeq). β Then live events from L+1. β
But wait β can S == L and the buffer contain events > L? No: the buffer is copied atomically with the seq under the lock. All buffered events have seq β€ S = L. β
And can S < L? Only if the hub entry was recreated (after Close) β which can't happen for the same jobID while the job is running... actually, hmm: hub.Close deletes the entry. If the job is re-run with the same jobID (impossible β jobID is a uuid per event). OK, S < L is impossible. But if it did happen, the client: resync S < L β no reload (S > L is false). Then buffered events (new stream, seq 1,2,3...) β ev.seq(1) <= lastSeq(L) β skip... and all new events are skipped until seq > L β which never comes (the new stream's seq starts at 1). The client renders nothing, stuck. Super edge case (impossible in practice). We could add `S < L β reload` to be safe. Let me add it: `if (lastSeq !== 0 && ev.seq !== lastSeq) outOfSync()`? Hmm wait, no β that's wrong for the normal reconnect case where S == L (in sync, don't reload). `ev.seq !== lastSeq` β reload on S < L or S > L. That's exactly what we want! On (re)connect: in sync iff S == L (or lastSeq==0, fresh page).
Hmm wait, but note: S == L means "the hub's latest seq equals what we last saw" β i.e., no events were published since we last saw one. But what if events were published and checkpointed (cleared from the buffer) since? Then S > L β reload. β Correct.
So the resync handler:
```js
case "resync":
if (lastSeq !== 0 && (typeof ev.seq !== "number" || ev.seq !== lastSeq)) outOfSync();
return;
```
Hmm, `typeof ev.seq !== "number"` β if the hub is fresh (seq 0, omitted from JSON) and lastSeq !== 0... that means the hub entry was recreated (impossible in practice) β reload. OK, safe.
Wait, actually, hmm: there's one more case. A fresh page (lastSeq=0) receives resync(seq=S). No-op (lastSeq==0). Then the buffered events. The first buffered event sets lastSeq=B0. But what if the buffer is empty (S==0, no events)? The client waits for live events. The first live event (seq 1) β lastSeq==0 β accept. β
And a fresh page with a non-empty buffer: resync(S), buffered B0..S. The client sets lastSeq=B0 on the first buffered event. β
Now, the gap detection for events (non-resync):
```js
if (typeof ev.seq === "number") {
if (lastSeq === 0) {
lastSeq = ev.seq;
} else if (ev.seq <= lastSeq) {
return; // replay
} else if (ev.seq > lastSeq + 1) {
outOfSync();
return;
} else {
lastSeq = ev.seq;
}
}
```
Hmm wait, the `ev.seq <= lastSeq β return (skip replay)` case: when does a client receive a replayed event without a reload? On reconnect with S == L (in sync): the buffer replays events β€ L β skip. β But those skipped events include the current block's start/deltas that the client already rendered before the drop. The client's DOM already has them. β Correct.
But hmm β what about this: reconnect with S == L, the buffer replays [start(10), delta(11), delta(12)], and the client had already rendered up to L=12 before the drop. Skip all three. The DOM has the block with the text from 10-12. β Then live: delta(13) β append. β
And: reconnect with S > L β reload. β (The static view has everything up to the last checkpoint. The fresh subscription gets the rest.)
OK, the design is sound. Now β one more thing to verify: the `status` event. It's published via Publish β gets a seq β goes through the seq check. If in sync, the client renders it: `es.close(); location.reload()`. β If the client missed events before status β gap β outOfSync() β reload (same). β
Now, let me also double-check the hub's `Close`:
```go
func (h *Hub) Close(jobID string) {
h.Publish(jobID, Event{Type: Status, Status: "done"})
...
}
```
Publish assigns a seq. β
Now, are there other places that construct livelog.Events? Let me grep. Also, let me check the hub tests to update/extend them.
Also β the `write` function in handleJobEvents marshals the event. The resync event `Event{Type: Resync, Seq: seq}` β `{"type":"resync","seq":N}`. β
Now, let me also think about **whether to persist whitespace-only blocks at all**. Currently, streamHooks persists `contentBuf.String()` even if it's whitespace-only. buildBlocks drops it on display. The stored log has a junk line. Harmless. Leave it (the display layer owns the trimming β per the #53 fix's design decision: "the stored log keeps the raw model output. This is a display-layer fix").
Now, let me write the tests:
**Hub tests (livelog/hub_test.go):** Let me read the existing tests first.
**Web tests:**
- Test that the SSE stream sends a resync first.
- Test that events carry a contiguous seq.
- Test the gap scenario: subscribe, drop events (fill the channel), reconnect β resync indicates a gap. Hmm, testing the client's JS logic is hard in Go. Test the server side: the seq is contiguous, the resync carries the correct seq. The JS logic is... hmm, there's no JS test infrastructure here. Let me check if there's a way to test the JS... the project is Go-only (no package.json). So the JS is verified by review + the server-side contract tests.
Let me also reconsider: **is there a simpler fix for the empty block that I'm missing?** Let me look at the issue once more...
"These are sometimes empty in the job log - I'm pretty sure there should be some text in there."
Hmm, OK, yet another scenario I haven't considered: **what if the model's content arrives in a message with `finish_reason: tool_calls`, and the content is real text?** That's the normal case β the block is rendered fine.
**What if the content is real text but arrives after the tool call results in the next turn?** No β each turn's content is in that turn's message.
**What about the `prevContent`/`prevReasoning` tracking in runLoop?**
```go
var prevContent, prevReasoning string
for {
c, err := streamer.Get()
...
completion = c
if len(c.Choices) > 0 {
msg := c.Choices[0].Message
if hooks.OnReasoningDelta != nil && len(msg.ReasoningContent) > len(prevReasoning) {
hooks.OnReasoningDelta(msg.ReasoningContent[len(prevReasoning):])
}
prevReasoning = msg.ReasoningContent
...
}
}
```
`msg` is `s.completion` β the accumulated message (the same pointer every time, mutated by Merge). `prevReasoning` is the previous snapshot. The delta = the new suffix. β Correct.
Hmm, one thing: `len(msg.ReasoningContent) > len(prevReasoning)` β if the server resets/replaces the content (non-monotonic), the delta logic breaks (no delta published, prev updated). OpenAI-compatible servers append. Fine.
OK, one more thought β **maybe the empty block is from the static view after all?** Let me re-verify buildBlocks... `case "reasoning", "content": text := strings.TrimSpace(l.Line); if text == "" { continue }`. So whitespace-only β skip. Non-whitespace β trimmed, non-empty. The template renders `{{.Text}}` β non-empty. So the static view can't produce an empty block-body. Confirmed. The empty block is from the live JS. β (Also consistent with the unindented HTML in the issue.)
So the fix is:
1. **JS: lazy block creation (wait for the first non-whitespace delta) + remove-if-empty on end** β fixes the deterministic empty shell from whitespace-only model output.
2. **Seq + resync + gap detection β reload** β fixes the empty/truncated/untrimmed blocks from dropped events (the "should have had some text in there" case).
Both together make the live view consistent with the static view in all cases.
Wait, actually, let me reconsider #2's scope once more. The seq mechanism touches: hub.go (Event struct, stream.seq, Publish, Subscribe), web.go (handleJobEvents: resync), templates.go (JS). Plus tests. It's a moderate, well-contained change. I think it's justified: the issue is literally "the live view shows blocks without their text", and silent event drops are the only way real text goes missing. The hub's own comment acknowledges drops happen ("before new events are dropped for it").
Hmm, that said... let me consider whether the drops are actually frequent enough to be the user's problem. The user says "sometimes empty". If it were only whitespace-only model output, the empty blocks would appear at specific points (whitespace-only turns) and vanish on reload. The user's "I'm pretty sure there should be some text in there" strongly suggests the text existed (they saw the job do the work).
Also β hmm, wait. Let me reconsider the background tab throttling. Chrome throttles background tabs: timers are clamped to 1/second, but EventSource is a network event β I believe it's delivered promptly even in background tabs (network activity isn't throttled the same way). But if the user's laptop sleeps, or the network stalls (WiFi), the TCP buffer fills, and when the connection resumes, the server's channel (256) may overflow β drops. On resume, the client's EventSource may detect the stall and reconnect (SSE has no built-in timeout detection... actually, the browser doesn't auto-reconnect on stall. It just receives the burst when the network resumes. The server's channel overflows during the stall β drops. The client receives a burst with gaps β with my fix, gap detected β reload. β Without the fix: the client renders the gappy stream β empty/truncated blocks. β This is exactly the user's scenario!)
OK, I'm confident in the fix. Let me also double-check the `Subscribe` signature change β it's used in web.go and the tests. Let me look at hub_test.go and web_test.go.
Now let me look at the existing tests for the hub and web packages:
Tool
π§ read_file
{"end_line": 200, "path": "internal/livelog/hub_test.go", "start_line": 1}
Arguments
{"end_line": 200, "path": "internal/livelog/hub_test.go", "start_line": 1}
Result
{"path":"internal/livelog/hub_test.go","content":"package livelog\n\nimport (\n\t\"testing\"\n\t\"time\"\n)\n\nfunc recv(t *testing.T, ch \u003c-chan Event) Event {\n\tt.Helper()\n\n\tselect {\n\tcase ev, ok := \u003c-ch:\n\t\tif !ok {\n\t\t\tt.Fatal(\"channel closed unexpectedly\")\n\t\t}\n\n\t\treturn ev\n\tcase \u003c-time.After(time.Second):\n\t\tt.Fatal(\"timed out waiting for event\")\n\t}\n\n\treturn Event{}\n}\n\nfunc TestSubscribeReplaysBufferedEvents(t *testing.T) {\n\th := NewHub()\n\n\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\tbuffered, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif len(buffered) != 2 {\n\t\tt.Fatalf(\"expected 2 buffered events, got %d\", len(buffered))\n\t}\n\tif buffered[1].Text != \"hi\" {\n\t\tt.Fatalf(\"unexpected buffered event: %+v\", buffered[1])\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \" there\"})\n\n\tev := recv(t, ch)\n\tif ev.Text != \" there\" {\n\t\tt.Fatalf(\"expected live delta %q, got %+v\", \" there\", ev)\n\t}\n}\n\nfunc TestCheckpointClearsBuffer(t *testing.T) {\n\th := NewHub()\n\n\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Checkpoint(\"job-1\")\n\n\tbuffered, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif len(buffered) != 0 {\n\t\tt.Fatalf(\"expected empty buffer after checkpoint, got %d events\", len(buffered))\n\t}\n}\n\nfunc TestCloseTerminatesSubscribers(t *testing.T) {\n\th := NewHub()\n\n\t_, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\th.Close(\"job-1\")\n\n\tev := recv(t, ch)\n\tif ev.Type != Status {\n\t\tt.Fatalf(\"expected terminal status event, got %+v\", ev)\n\t}\n\n\tselect {\n\tcase _, ok := \u003c-ch:\n\t\tif ok {\n\t\t\tt.Fatal(\"expected channel to be closed after status event\")\n\t\t}\n\tcase \u003c-time.After(time.Second):\n\t\tt.Fatal(\"timed out waiting for channel close\")\n\t}\n}\n\nfunc TestSubscribeAfterCloseGetsEmptyBuffer(t *testing.T) {\n\th := NewHub()\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Close(\"job-1\")\n\n\tbuffered, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif len(buffered) != 0 {\n\t\tt.Fatalf(\"expected fresh empty state for a job re-subscribed after close, got %d events\", len(buffered))\n\t}\n\n\tselect {\n\tcase ev := \u003c-ch:\n\t\tt.Fatalf(\"did not expect any live event, got %+v\", ev)\n\tcase \u003c-time.After(50 * time.Millisecond):\n\t}\n}\n\nfunc TestCancelUnregistersSubscriber(t *testing.T) {\n\th := NewHub()\n\n\t_, ch, cancel := h.Subscribe(\"job-1\")\n\tcancel()\n\n\tselect {\n\tcase _, ok := \u003c-ch:\n\t\tif ok {\n\t\t\tt.Fatal(\"expected channel to be closed after cancel\")\n\t\t}\n\tcase \u003c-time.After(time.Second):\n\t\tt.Fatal(\"timed out waiting for channel close after cancel\")\n\t}\n\n\t// Publishing after cancel must not panic or block.\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n}","start_line":1,"end_line":124,"total_lines":124,"truncated":false}
Thinking
Alright, let's check web_test.go to understand the test setup for the web server (in particular, how the SSE endpoint is being tested).
Tool
π§ read_file
{"end_line": 160, "path": "internal/web/web_test.go", "start_line": 1}
Arguments
{"end_line": 160, "path": "internal/web/web_test.go", "start_line": 1}
Result
{"path":"internal/web/web_test.go","content":"package web\n\nimport (\n\t\"context\"\n\t\"fmt\"\n\t\"net/http\"\n\t\"net/http/httptest\"\n\t\"path/filepath\"\n\t\"strings\"\n\t\"testing\"\n\t\"time\"\n\n\t\"github.com/abrander/zoo/internal/config\"\n\t\"github.com/abrander/zoo/internal/forgejo\"\n\t\"github.com/abrander/zoo/internal/livelog\"\n\t\"github.com/abrander/zoo/internal/store\"\n)\n\nfunc testServer(t *testing.T) (*Server, *store.Store) {\n\tt.Helper()\n\n\tst, err := store.Open(filepath.Join(t.TempDir(), \"zoo.db\"))\n\tif err != nil {\n\t\tt.Fatal(err)\n\t}\n\tt.Cleanup(func() { st.Close() })\n\n\tcfg := \u0026config.Config{\n\t\tLLMs: []config.LLM{{Name: \"qwen\", OpenAI: \"https://example.com\", Model: \"qwen3\"}},\n\t\tAgents: []config.Agent{{Name: \"leon\", LLM: \"qwen\"}},\n\t\tEvents: []config.Event{{Kind: config.EventIssueNew, Agent: \"leon\"}},\n\t\tEnvironment: config.Environment{DockerImage: \"debian:unstable\", MaxLive: 2},\n\t}\n\n\t// No Forgejo client: pages render without avatars.\n\treturn New(cfg, st, livelog.NewHub(), nil), st\n}\n\nfunc TestIndexRenders(t *testing.T) {\n\ts, _ := testServer(t)\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/\", nil))\n\n\tif rr.Code != http.StatusOK {\n\t\tt.Fatalf(\"expected 200, got %d: %s\", rr.Code, rr.Body.String())\n\t}\n\tif !strings.Contains(rr.Body.String(), \"leon\") {\n\t\tt.Fatalf(\"expected agent name in output, got %s\", rr.Body.String())\n\t}\n}\n\nfunc TestJobsAndDetail(t *testing.T) {\n\ts, st := testServer(t)\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.AppendLog(ctx, \"job-1\", \"stdout\", \"hello\"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs\", nil))\n\tif rr.Code != http.StatusOK || !strings.Contains(rr.Body.String(), \"job-1\") {\n\t\tt.Fatalf(\"unexpected jobs page: %d %s\", rr.Code, rr.Body.String())\n\t}\n\n\trr = httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1\", nil))\n\tif rr.Code != http.StatusOK || !strings.Contains(rr.Body.String(), \"hello\") {\n\t\tt.Fatalf(\"unexpected job detail page: %d %s\", rr.Code, rr.Body.String())\n\t}\n\n\t// job-1 was never marked started/finished, so it's still \"live\":\n\t// hitting /events should stream whatever's currently buffered in the\n\t// hub (not yet checkpointed/persisted) and then wait for more, until\n\t// the request context is done.\n\ts.hub.Publish(\"job-1\", livelog.Event{Type: livelog.ContentDelta, Text: \"streaming\"})\n\n\tevCtx, cancel := context.WithTimeout(context.Background(), 200*time.Millisecond)\n\tdefer cancel()\n\n\trr = httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1/events\", nil).WithContext(evCtx))\n\tif rr.Code != http.StatusOK || !strings.Contains(rr.Body.String(), \"streaming\") {\n\t\tt.Fatalf(\"unexpected events response: %d %s\", rr.Code, rr.Body.String())\n\t}\n\n\t// A finished job isn't live: /events should return immediately with\n\t// nothing to stream, so the client falls back to the static page.\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-2\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 2}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.MarkJobFinished(ctx, \"job-2\", store.JobSucceeded, \"\"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\trr = httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-2/events\", nil))\n\tif rr.Code != http.StatusOK || rr.Body.Len() != 0 {\n\t\tt.Fatalf(\"expected empty response for a non-live job, got %d %q\", rr.Code, rr.Body.String())\n\t}\n}\n\n// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved.\nfunc TestJobDetailTrimsBlockWhitespace(t *testing.T) {\n\ts, st := testServer(t)\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.MarkJobFinished(ctx, \"job-1\", store.JobSucceeded, \"\"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.AppendLog(ctx, \"job-1\", \"content\", \"\\nNow the remaining tool callers:\\n\\n\\n\"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\t// A block that is nothing but whitespace should not render at all.\n\tif err := st.AppendLog(ctx, \"job-1\", \"content\", \" \\n\\t \"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.AppendLog(ctx, \"job-1\", \"reasoning\", \" \\ninner\\nlines\\nkept\\n \"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\tr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(r, httptest.NewRequest(http.MethodGet, \"/jobs/job-1\", nil))\n\tif r.Code != http.StatusOK {\n\t\tt.Fatalf(\"expected 200, got %d: %s\", r.Code, r.Body.String())\n\t}\n\n\tbody := r.Body.String()\n\tif !strings.Contains(body, `\u003cdiv class=\"block-body\"\u003eNow the remaining tool callers:\u003c/div\u003e`) {\n\t\tt.Fatalf(\"expected trimmed content block, got: %s\", body)\n\t}\n\tif strings.Contains(body, \"\u003cdiv class=\\\"block-body\\\"\u003e\\n\") {\n\t\tt.Fatalf(\"block body still starts with a newline: %s\", body)\n\t}\n\tif got := strings.Count(body, `class=\"block block-content\"`); got != 1 {\n\t\tt.Fatalf(\"expected exactly one content block (whitespace-only one dropped), got %d: %s\", got, body)\n\t}\n\tif !strings.Contains(body, \"inner\\nlines\\nkept\") {\n\t\tt.Fatalf(\"expected internal newlines to be preserved, got: %s\", body)\n\t}\n}\n\nfunc TestAuthGate(t *testing.T) {\n\tst, err := store.Open(filepath.Join(t.TempDir(), \"zoo.db\"))\n\tif err != nil {\n\t\tt.Fatal(err)\n\t}\n\tdefer st.Close()\n","start_line":1,"end_line":160,"total_lines":253,"truncated":true}
Thinking
Okay, I've got the full picture now. Let me check the rest of web_test.go, then verify that the build passes and the tests run.
Let me lay out the final plan:
## Diagnosis
The empty `block-body` in the job log is a problem with the **live (SSE) view**, and there are two causes:
1. **Whitespace-only model output β empty block shell.** When the model emits a content (or reasoning) message that is only whitespace (e.g. `"\n"` β common when a tool call accompanies a trivial content field), the live JS creates a block on `content_start` and trims it to `""` on `content_end` β leaving an empty `.block-body` in the DOM. The static view correctly discards whitespace-only blocks (`buildBlocks`), so the block disappears on reload. Fix: create the block lazily (on the first non-whitespace delta), and as a safety net, remove the block on end if it's empty.
2. **Dropped SSE events β desync.** `livelog.Hub` intentionally drops events for slow subscribers (full 256-slot channel). The client's block state machine (`content_start`/`delta`/`end`) is not resilient to gaps: a dropped delta β empty/truncated block ("there should be some text in there"); a dropped `content_end` β untrimmed block (extra vertical space) and an orphaned block on the next turn. Fix: give every event a per-job monotonically increasing sequence number; the server sends a `resync` marker (with the current seq) on (re)connect; the client detects gaps/replays and falls back to the static page (the source of truth) via `location.reload()`.
## Changes
1. `internal/livelog/hub.go`:
- `Event.Seq uint64` (json `seq,omitempty`).
- `stream.seq uint64`; `Publish` assigns `s.seq+1` under the lock.
- `Subscribe` returns the current seq alongside the buffer (atomic under the same lock).
- Add a `Resync Type = "resync"` constant.
- Update the doc comment about drops (drops are now recoverable: the client detects the gap and reloads).
2. `internal/web/web.go`:
- `handleJobEvents`: after subscribing, write a `resync` event carrying the current seq before the buffered events.
3. `internal/web/templates.go` (JS):
- Track `lastSeq`; handle `resync`; skip replays (seq <= lastSeq); on a gap (seq > lastSeq+1) β close + reload.
- Lazy block creation for reasoning/content: buffer deltas until the first non-whitespace text, then create the block; on end, trim and remove the block if empty (defensive).
4. Tests:
- `hub_test.go`: seq is monotonically increasing per job; Subscribe returns the current seq; the signature change.
- `web_test.go`: the SSE stream starts with a resync carrying the current seq; events carry a contiguous seq.
Alright, let me check the rest of web_test.go and then run the build/tests to establish a baseline.
Let me see the rest of web_test.go and run the baseline build/tests:
Tool
π§ read_file
{"end_line": 253, "path": "internal/web/web_test.go", "start_line": 160}
Arguments
{"end_line": 253, "path": "internal/web/web_test.go", "start_line": 160}
Result
{"path":"internal/web/web_test.go","content":"\n\tcfg := \u0026config.Config{Web: \u0026config.Web{Token: \"secret\"}}\n\ts := New(cfg, st, livelog.NewHub(), nil)\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs\", nil))\n\tif rr.Code != http.StatusUnauthorized {\n\t\tt.Fatalf(\"expected 401 without token, got %d\", rr.Code)\n\t}\n\n\treq := httptest.NewRequest(http.MethodGet, \"/jobs\", nil)\n\treq.Header.Set(\"Authorization\", \"Bearer secret\")\n\trr = httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, req)\n\tif rr.Code != http.StatusOK {\n\t\tt.Fatalf(\"expected 200 with correct token, got %d\", rr.Code)\n\t}\n}\n\n// TestJobsShowAgentAvatars verifies the jobs pages render each agent's\n// Forgejo avatar, and that an unresolvable avatar (unknown user) degrades\n// to no image instead of breaking the page.\nfunc TestJobsShowAgentAvatars(t *testing.T) {\n\t// Minimal in-test Forgejo API: the version probe the SDK makes when\n\t// the client is constructed, plus per-user profile lookups.\n\tavatars := map[string]string{\n\t\t\"leon\": \"https://forgejo.example/avatars/leon\",\n\t}\n\n\tapi := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {\n\t\tif r.URL.Path == \"/api/v1/version\" {\n\t\t\tw.Header().Set(\"Content-Type\", \"application/json\")\n\t\t\tfmt.Fprint(w, `{\"version\":\"1.23.0\"}`)\n\n\t\t\treturn\n\t\t}\n\n\t\tif user, ok := strings.CutPrefix(r.URL.Path, \"/api/v1/users/\"); ok {\n\t\t\tif url, ok := avatars[user]; ok {\n\t\t\t\tw.Header().Set(\"Content-Type\", \"application/json\")\n\t\t\t\tfmt.Fprintf(w, `{\"login_name\":%q,\"avatar_url\":%q}`, user, url)\n\n\t\t\t\treturn\n\t\t\t}\n\t\t}\n\n\t\thttp.NotFound(w, r)\n\t}))\n\tt.Cleanup(api.Close)\n\n\tfg, err := forgejo.NewClient(config.Forgejo{URL: api.URL, Token: \"test\"})\n\tif err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\tst, err := store.Open(filepath.Join(t.TempDir(), \"zoo.db\"))\n\tif err != nil {\n\t\tt.Fatal(err)\n\t}\n\tt.Cleanup(func() { st.Close() })\n\n\ts := New(\u0026config.Config{}, st, livelog.NewHub(), fg)\n\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\t// \"ghost\" doesn't exist on the mock Forgejo: the page must still\n\t// render, just without an avatar for that job.\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-2\", EventKind: \"issue:new\", Agent: \"ghost\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 2}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs\", nil))\n\tif rr.Code != http.StatusOK {\n\t\tt.Fatalf(\"expected 200, got %d: %s\", rr.Code, rr.Body.String())\n\t}\n\n\tbody := rr.Body.String()\n\tif !strings.Contains(body, `src=\"https://forgejo.example/avatars/leon\"`) {\n\t\tt.Fatalf(\"expected leon's avatar on the jobs page, got: %s\", body)\n\t}\n\tif !strings.Contains(body, \"job-2\") {\n\t\tt.Fatalf(\"expected the unknown-agent job to still render, got: %s\", body)\n\t}\n\n\trr = httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1\", nil))\n\tif rr.Code != http.StatusOK || !strings.Contains(rr.Body.String(), `src=\"https://forgejo.example/avatars/leon\"`) {\n\t\tt.Fatalf(\"expected leon's avatar on the job detail page, got %d: %s\", rr.Code, rr.Body.String())\n\t}\n}","start_line":160,"end_line":253,"total_lines":253,"truncated":false}
Tool
π§ bash
{"command": "cd /project && go build ./... && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -20"}
Arguments
{"command": "cd /project && go build ./... && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -20"}
Result
ok github.com/abrander/zoo/internal/livelog 0.052s
ok github.com/abrander/zoo/internal/web 1.006s
go: downloading github.com/docker/docker v28.5.2+incompatible
go: downloading github.com/hashicorp/hcl/v2 v2.24.0
go: downloading codeberg.org/mvdkleijn/forgejo-sdk/forgejo/v2 v2.2.0
go: downloading github.com/google/uuid v1.6.0
go: downloading modernc.org/sqlite v1.56.0
go: downloading github.com/docker/go-connections v0.8.1
go: downloading github.com/docker/go-units v0.5.0
go: downloading github.com/moby/docker-image-spec v1.3.1
go: downloading github.com/opencontainers/image-spec v1.1.1
go: downloading github.com/containerd/errdefs v1.0.0
go: downloading github.com/containerd/errdefs/pkg v0.3.0
go: downloading github.com/distribution/reference v0.6.0
go: downloading github.com/opencontainers/go-digest v1.0.0
go: downloading github.com/pkg/errors v0.9.1
go: downloading go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.70.0
go: downloading go.opentelemetry.io/otel/trace v1.45.0
go: downloading go.opentelemetry.io/otel v1.45.0
go: downloading github.com/42wim/httpsig v1.2.3
go: downloading github.com/go-fed/httpsig v1.1.0
go: downloading github.com/hashicorp/go-version v1.7.0
go: downloading golang.org/x/crypto v0.39.0
go: downloading github.com/felixge/httpsnoop v1.1.0
go: downloading go.opentelemetry.io/otel/metric v1.45.0
go: downloading github.com/agext/levenshtein v1.2.1
go: downloading github.com/apparentlymart/go-textseg/v15 v15.0.0
go: downloading github.com/mitchellh/go-wordwrap v1.0.1
go: downloading github.com/zclconf/go-cty v1.16.3
go: downloading github.com/go-logr/logr v1.4.4
go: downloading golang.org/x/sys v0.47.0
go: downloading github.com/google/go-cmp v0.7.0
go: downloading github.com/go-logr/stdr v1.2.2
go: downloading go.opentelemetry.io/auto/sdk v1.2.1
go: downloading github.com/cespare/xxhash/v2 v2.3.0
go: downloading golang.org/x/text v0.40.0
go: downloading modernc.org/libc v1.74.4
go: downloading github.com/dustin/go-humanize v1.0.1
go: downloading modernc.org/mathutil v1.7.1
go: downloading modernc.org/memory v1.11.0
go: downloading github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec
Thinking
Baseline is green. Now let's implement the fix.
## Summary of diagnosis (for the final comment)
The empty `block-body` div is generated by the **live SSE view** (note that in the issue's empty example, the HTML has no indentation β it's a DOM node created by JS, not the static template). There are two root causes:
1. **Whitespace-only model output**: the live JS creates a block on `content_start`, and on `content_end` trims the accumulated text. If the model's content is whitespace-only (e.g. `"\n"` β a common thing when a message is mainly a tool call), the block is left as an empty shell. The static view correctly discards such blocks (`buildBlocks`), so they disappear on reload β which is why the reporter couldn't reproduce it on old logs.
2. **Dropped SSE events desync the live view**: `livelog.Hub` drops events for slow subscribers (channel full β e.g. a background tab, a network stall). The client's start/delta/end state machine can't recover from gaps:
- dropped `content_delta` β empty or truncated block ("there should be some text in there");
- dropped `content_end` β the block stays untrimmed (extra vertical space β the issue's second example) and the next `content_start` orphans it.
## Fix
1. **JS (templates.go)**:
- Lazily create reasoning/content blocks on the first *non-whitespace* delta (buffering whitespace-only prefixes). Whitespace-only model output no longer produces an empty shell at all.
- On `*_end`, trim, and if the result is empty, remove the block (defensive; matches the static view).
- Track event sequence numbers; on a gap (or a resync marker showing we've fallen behind), close the stream and `location.reload()` β the static page is the source of truth and is always complete.
2. **Hub (hub.go)**: assign each published event a per-job monotonically increasing `Seq`; `Subscribe` returns the current seq atomically with the buffer snapshot; add a `Resync` event type.
3. **SSE handler (web.go)**: on (re)connect, send a `resync` marker carrying the hub's current seq as the first message, so that even if the buffer is empty, the client can detect that it has fallen behind.
Now let's write the code.
### hub.go
```go
type Type string
const (
ReasoningStart Type = "reasoning_start"
ReasoningDelta Type = "reasoning_delta"
ReasoningEnd Type = "reasoning_end"
ContentStart Type = "content_start"
ContentDelta Type = "content_delta"
ContentEnd Type = "content_end"
Tool Type = "tool"
Status Type = "status"
// Resync is not published through Publish; the web layer sends it
// as the first message of a new SSE subscription, carrying the
// job's current sequence number, so the client can tell whether it
// missed any events since its last (re)connect.
Resync Type = "resync"
)
type Event struct {
Type Type `json:"type"`
// Seq is the job's monotonically increasing sequence number,
// assigned by Publish. Clients use it to detect dropped events
// (gaps) and fall back to the static page.
Seq uint64 `json:"seq,omitempty"`
Text string `json:"text,omitempty"`
Name string `json:"name,omitempty"`
Arguments string `json:"arguments,omitempty"`
Result string `json:"result,omitempty"`
Error bool `json:"error,omitempty"`
Status string `json:"status,omitempty"`
}
```
Update the subChanBuffer comment:
```go
// subChanBuffer bounds how many events a slow subscriber can lag behind
// by before new events are dropped for it. Generous for a single-user
// local dashboard. A dropped event is recoverable: every event carries
// a monotonically increasing Seq, so the client detects the gap and
// falls back to the static page (which is always complete) instead of
// rendering a desynced block.
```
stream:
```go
type stream struct {
mu sync.Mutex
buf []Event
subs map[chan Event]struct{}
seq uint64
}
```
Publish:
```go
func (h *Hub) Publish(jobID string, ev Event) {
s := h.get(jobID)
s.mu.Lock()
defer s.mu.Unlock()
s.seq++
ev.Seq = s.seq
s.buf = append(s.buf, ev)
...
}
```
Subscribe:
```go
// Subscribe returns the events currently buffered for jobID (i.e. not
// yet checkpointed), the job's current sequence number (the Seq of the
// most recent published event, 0 if none), and a channel of everything
// published from this point on. The buffer and the seq are taken under
// one lock, so the seq is always >= every buffered event's Seq. The
// returned cancel func must be called when the caller is done reading,
// to unregister and close the channel.
func (h *Hub) Subscribe(jobID string) (buffered []Event, seq uint64, ch <-chan Event, cancel func()) {
s := h.get(jobID)
s.mu.Lock()
defer s.mu.Unlock()
buffered = append([]Event(nil), s.buf...)
seq = s.seq
...
}
```
### web.go handleJobEvents
```go
buffered, seq, ch, cancel := s.hub.Subscribe(id)
defer cancel()
write := func(ev livelog.Event) bool { ... }
// First tell the client where the hub is at: if it has seen events
// since its last (re)connect (seq > what it last rendered), it missed
// some that are no longer replayable and must fall back to the static
// page. Without this, a client that reconnects to an empty buffer
// would sit desynced until the next event happened to arrive.
if !write(livelog.Event{Type: livelog.Resync, Seq: seq}) {
return
}
for _, ev := range buffered {
if !write(ev) {
return
}
}
```
Wait β one issue: the `write` function marshals the event. For Resync with Seq=0, the JSON will be `{"type":"resync"}` (seq is omitted). The client handles the missing seq: `typeof ev.seq !== "number"` β treat as 0? Let's write the client's resync handler:
```js
case "resync":
// The hub's latest seq at (re)connect time. If we've seen events
// since our last one, we missed some that are no longer replayable
// β the live view is out of sync; fall back to the static page.
if (lastSeq !== 0 && (typeof ev.seq !== "number" || ev.seq !== lastSeq)) {
resyncWithStatic();
}
return;
```
Hmm wait, `ev.seq !== lastSeq` β if ev.seq is missing (undefined), `undefined !== lastSeq` is true β resync. When would resync have no seq? A new hub entry (seq 0) β which for a reconnecting client means the hub entry was recreated β definitely out of sync β reload. Correct.
Hmm, but wait: for a fresh page (lastSeq === 0), resync is a no-op. β
### JS in templates.go
Current:
```js
(function() {
var jobID = {{.Job.ID}};
var log = document.getElementById("log");
var reasoningBody = null;
var contentBody = null;
function nearBottom() { ... }
function newBlock(kind, label) { ... }
function newToolBlock(ev) { ... }
var es = new EventSource("/jobs/" + jobID + "/events");
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
var shouldScroll = nearBottom();
switch (ev.type) {
case "reasoning_start":
reasoningBody = newBlock("reasoning", "Thinking");
break;
case "reasoning_delta":
if (reasoningBody) reasoningBody.textContent += ev.text;
break;
case "reasoning_end":
// Model output routinely starts/ends with newlines; drop them
// so the finished block matches the static (trimmed) view.
if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();
reasoningBody = null;
break;
case "content_start":
contentBody = newBlock("content", null);
break;
case "content_delta":
if (contentBody) contentBody.textContent += ev.text;
break;
case "content_end":
if (contentBody) contentBody.textContent = contentBody.textContent.trim();
contentBody = null;
break;
case "tool":
newToolBlock(ev);
break;
case "status":
es.close();
location.reload();
return;
}
if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);
};
})();
```
New:
```js
(function() {
var jobID = {{.Job.ID}};
var log = document.getElementById("log");
// Each block kind has a DOM body (null while no block is open) and a
// text buffer used until the first non-whitespace delta arrives:
// model output routinely starts with newlines, and a block that ends
// up whitespace-only must not render at all (the static view drops
// those blocks too). Creating the block lazily on the first real
// text is what keeps a whitespace-only turn from flashing an empty
// block shell (issue #60).
var reasoningBody = null, reasoningBuf = "";
var contentBody = null, contentBuf = "";
// lastSeq is the sequence number of the last event rendered. The
// server numbers every event per job and sends a "resync" marker
// with the current number on (re)connect; a gap means events were
// dropped (slow tab, network stall) and the block state below can
// no longer be trusted β the static page is the source of truth.
var lastSeq = 0;
function resyncWithStatic() {
es.close();
location.reload();
}
function nearBottom() { ... }
function newBlock(kind, label) { ... }
function newToolBlock(ev) { ... }
function openBlock(kind, label, text) {
var body = newBlock(kind, label);
body.textContent = text;
return body;
}
// appendDelta extends the open block of kind ("reasoning"/"content")
// with delta, creating the block on the first non-whitespace text.
// Returns true if the block's DOM changed (for scrolling).
...
```
Hmm, let me restructure more cleanly. I'll write a helper that handles both kinds via a state object:
```js
var blocks = {
reasoning: { body: null, buf: "" },
content: { body: null, buf: "" }
};
function onDelta(kind, delta) {
var b = blocks[kind];
if (b.body) {
b.body.textContent += delta;
return;
}
b.buf += delta;
if (b.buf.trim() === "") return; // whitespace so far: no block yet
b.body = newBlock(kind, kind === "reasoning" ? "Thinking" : null);
b.body.textContent = b.buf;
b.buf = "";
}
function onEnd(kind) {
var b = blocks[kind];
if (b.body) {
// Model output routinely starts/ends with newlines; drop them so
// the finished block matches the static (trimmed) view, and drop
// the block entirely if nothing is left.
b.body.textContent = b.body.textContent.trim();
if (b.body.textContent === "") b.body.parentElement.remove();
b.body = null;
}
b.buf = "";
}
```
Wait, `b.body.parentElement.remove()` β the block div is `b.body.parentElement` (the body div's parent is the block div). β
And onmessage:
```js
var es = new EventSource("/jobs/" + jobID + "/events");
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
if (ev.type === "resync") {
// The hub's latest sequence number at (re)connect time. If we
// have seen events since our last one, we missed some that are
// no longer replayable β the live view is out of sync.
if (lastSeq !== 0 && (typeof ev.seq !== "number" || ev.seq !== lastSeq)) {
resyncWithStatic();
}
return;
}
if (typeof ev.seq === "number") {
if (lastSeq === 0) {
lastSeq = ev.seq; // joining mid-stream (fresh page or replay)
} else if (ev.seq <= lastSeq) {
return; // replayed event we already rendered
} else if (ev.seq > lastSeq + 1) {
resyncWithStatic(); // gap: events were dropped
return;
} else {
lastSeq = ev.seq;
}
}
var shouldScroll = nearBottom();
switch (ev.type) {
case "reasoning_start":
blocks.reasoning.body = null;
blocks.reasoning.buf = "";
break;
case "reasoning_delta":
onDelta("reasoning", ev.text);
break;
case "reasoning_end":
onEnd("reasoning");
break;
case "content_start":
blocks.content.body = null;
blocks.content.buf = "";
break;
case "content_delta":
onDelta("content", ev.text);
break;
case "content_end":
onEnd("content");
break;
case "tool":
newToolBlock(ev);
break;
case "status":
es.close();
location.reload();
return;
}
if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);
};
```
Hmm wait, `resyncWithStatic` references `es` before it's defined β `es` is defined after the function, but the function is only called after `es` exists (onmessage fires after EventSource is constructed). JS hoisting: `function resyncWithStatic()` is hoisted; `es` is a `var` in the same scope β by the time onmessage runs, `es` is assigned. β No problem.
One issue: on a "resync" event, we `return` before `shouldScroll` β no problem, no DOM change.
Another subtle point: `ev.seq <= lastSeq β return` (skip replay). But what if a replayed event is a `content_end` for a block that was open in the DOM? Example: the client rendered start(10), delta(11), dropped delta(12), end(13), and reconnected in sync (S==Lβ¦ wait, if it dropped 12, 13 then S >= 13 > L=11 β resync triggers a reload. So in-sync replay only replays events the client already rendered. β Skipping is correct.
Hmm, wait β is that really true? "In sync" means S == L, i.e. no new events have been published since the client last saw one. All buffered events have seq β€ S == L. The client has rendered all events up to Lβ¦ has it really? The client's lastSeq=L means it successfully processed the event with seq L. Events 1..L: did it process them all? If it dropped some (from the channel) but the connection stayed alive and it kept receiving later eventsβ¦ e.g. it dropped event 5 but received 6, 7, β¦, L. Then lastSeq=L but event 5 was never rendered! And on reconnect, S==L β "in sync" β replay skips 5 (seq β€ L) β event 5 is lost forever (until the next gap triggers a reloadβ¦ which may never come).
Hmm! So the "skip replay" logic has a hole: the client can't distinguish "I rendered event 5" from "I dropped event 5" β both look like seq β€ lastSeq.
How likely is this? Channel drops happen when the channel is full (256 pending). If the channel is full, the client is way behind β it's not processing events at all. When it catches up, it receives a burst; events in between may have been dropped. So yes, this is possible: the client processes 1..4, the channel fills, 5..30 are dropped, 31..L are received. lastSeq=L, but 5..30 were lost. On reconnect, S==L β replay skips 5..L (all β€ L) β the loss persists.
To fix this properly, the client needs to track the expected seq strictly: it must know that it has rendered every event up to lastSeq. That is, the client should reject (treat as a gap) any event with seq != lastSeq+1 β including replays! But then, on a normal reconnect where the buffer replays events the client already rendered (seq β€ L), the first replayed event (seq B0 < L+1) would be treated as a gap β reload. That's a false positive (unnecessary reload) but safe (the static view is correct).
Hmm. Trade-off:
- Option A (skip replays): risk of silent loss in the "dropped in the middle, caught up later" case (rare, requires a precise drop pattern).
- Option B (strict contiguity, reload on any non-contiguous): safe, but a normal reconnect with a non-empty buffer always reloads (false positive). How common is a reconnect with a non-empty buffer? Reconnects happen on network blips / server restarts. The buffer is non-empty when a block is in progress (not yet checkpointed) β which is most of the time during a run! So Option B would reload on nearly every reconnect. Reloading is somewhat disruptive (scroll position lost, though the page auto-scrolls to the bottomβ¦ the static page shows all blocks; the user loses their scroll position mid-log). Hmm.
Wait, actually β hmm, let me reconsider. Is Option B's false positive really that bad? A reload gives the complete static view + a fresh subscription. The user sees a brief flicker. For a single-user local dashboard, that's acceptable. And correctness > smoothness here.
But Option A's silent loss is worse: the user sees a block missing text, and it stays wrong until the next gap or the final reload. That's exactly the reported bug!
Hmm, can we do better? What if the client tracked not just lastSeq but also "did I render every event up to lastSeq"? That's the strict contiguity check β Option B. The only way to avoid the false-positive reload on reconnect is to dedupe replays, which requires knowing which events were rendered β i.e. strict contiguity from the start.
Wait wait. Let me think again. On a fresh page (lastSeq=0), the client receives the replay buffer. It accepts the first event at any seq (sets lastSeq=B0) and requires strict contiguity thereafter. So a fresh page renders the replay correctly (the buffer is contiguous by construction β it's a slice of the seq stream).
On reconnect (lastSeq=L>0): the client receives resync(S).
- S > L β reload (definite gap: events L+1..S were published; the client missed at leastβ¦ hmm, did it? The client may have received some of L+1..S via the channel before the connection dropped! lastSeq=L means the last one it processed was L. If it received L+1..S-1 but the connection dropped before it processed themβ¦ no wait β lastSeq is updated when the event is processed (onmessage). If the connection dropped with events in flight (in the TCP buffer / browser queue), they were never processed β lastSeq=L, and the events L+1..S exist in the hub's buffer (if not checkpointed) β the replay would deliver them!
Oh. So on reconnect, if the buffer still contains the in-flight events, the replay heals the client β no reload needed! The replayed events have seqs L+1, L+2, β¦ β strictly contiguous with lastSeq! The client can render them normally!
So the correct logic on reconnect:
- resync(S):
- If S == L: the hub hasn't published anything new since L. The buffer (if any) contains only events β€ L β the replay would be duplicates β skip (the client already has themβ¦ assuming strict contiguity up to L).
- If S > L: events L+1..S were published. If the buffer contains them (the buffer wasn't checkpointed past L), the replay will deliver them contiguously β the client can heal without a reload. If the buffer was checkpointed (cleared) in the meantime, the replay starts above L+1 (or is empty) β gap β reload.
So the client doesn't need to decide at resync time! It just applies the strict contiguity rule to every event (including the replay):
```js
if (lastSeq === 0) {
lastSeq = ev.seq; // first event (fresh page): accept
} else if (ev.seq === lastSeq + 1) {
lastSeq = ev.seq; // contiguous: render
} else if (ev.seq <= lastSeq) {
// Replay of something we already rendered (reconnect with a
// non-checkpointed buffer, no gap): skip.
return;
} else {
// Gap: ev.seq > lastSeq + 1 and not a replay β we missed events.
resyncWithStatic();
return;
}
```
Wait, but this is Option A again (skip replays), which has the "dropped in the middle, caught up later" hole. Hmm, no wait β let me re-examine that hole under the strict rule:
Scenario: the client renders 1..4 (lastSeq=4). The channel fills. Events 5..30 are dropped from the channel. Events 31..L are received and rendered (lastSeq=L). The connection is alive (no reconnect). The client believes it has 1..L but is missing 5..30.
Under any client-side logic, this loss is undetectable without a reconnect (the client sees a contiguous stream 31..L). The only detection is: on the next reconnect, the resync/replay reveals the truth:
- If the buffer still has 5..30 (not checkpointed): the replay delivers 5..30 β but the client's lastSeq=L β₯ 30 β `ev.seq <= lastSeq` β skip β the loss persists. β
- If the buffer was checkpointed: the replay is empty or starts above L β resync S > Lβ¦
Hmm, I see, so under Option A, the "dropped in the middle, caught up later, then reconnect" case persists the loss. Under Option B (strict: any ev.seq != lastSeq+1 β reload):
- Reconnect, the buffer replays 5 (β€ L) β 5 != L+1 β reload β healed. β
- Reconnect, the buffer is empty, S == L β no events β the client sitsβ¦ with the loss (5..30) still undetected! β (Same as A β undetectable until the next event: the next event L+1 == lastSeq+1 β render β the loss persists. ββ)
Ugh. So even Option B can't catch the "dropped in the middle, caught up later, buffer checkpointed" case. Because from the client's perspective, the stream looks contiguous.
Fundamental problem: the client can only detect gaps at the moment they happen (an event arrives with a seq jump). A drop that's hidden by later contiguous events is undetectable without out-of-band info.
Out-of-band info: the server knows how many events were dropped for this subscriber! The hub's fanout could count drops per subscriberβ¦ but subscribers are anonymous channels; the SSE handler could track drops for its own channel andβ¦ send a "you dropped N events" notification? That requires the hub to report per-subscriber drops. Hmm, that's more machinery: the hub's Publish does a non-blocking send; the handler can't easily know when its channel's send failedβ¦ actually, it can: the hub could give each subscriber a way to check. E.g. `stream.subs` maps channel β *subState{dropped int}. On a failed send, dropped++. The SSE handler periodically (or on each event) checks its own dropped count and, if > 0, sends a "dropped" control event β the client reloads.
Hmm, that's actually clean and complete! Let me think:
- Hub: `subs map[chan Event]*subscriber`, `subscriber{ch chan Event, dropped int}`.
- Publish: for each sub: try to send; on failure, sub.dropped++ (under s.mu).
- New method: `h.SubscriberDropped(jobID, ch) int`? The SSE handler has the channel from Subscribe. It can poll: after writing each event (or on a ticker), check the dropped count; if it increased β write a control event `{"type":"resync","dropped":true}`β¦
Hmm wait, but there's a subtlety: the dropped count is under s.mu; the handler reads it between writes. Race: an event is dropped after the check, before the next check β detected on the next check. No problem β detection is eventually consistent, and the client reloads on the next control event. But if the job ends right after (status event), the client reloads on status anyway. β
But hmm, this adds real complexity to the hub (subscriber struct, drop counting, a query method). And the "resync on connect" marker is still needed for the reconnect case.
Let me step back and think about what's proportionate.
The reported bug: empty block bodies. The causes:
1. Whitespace-only model output (deterministic) β fixed by lazy creation. No seq needed.
2. Dropped events (rare: requires a slow tab / network stall) β the block is empty/truncated/untrimmed until reload.
For cause 2, the seq + resync + strict contiguity (Option B) approach catches:
- Drops at the tail (most common: the channel fills, the client falls behind, the connection drops or the client processes a burst with jumps) β detected on the jump. β
- Reconnect after a checkpoint β detected by resync. β
- Reconnect with a healing replay β the replay is contiguous β no reload, healed. β (Option B handles this: replayed events with seq == lastSeq+1 render normally; only replays with seq β€ lastSeq (duplicates) trigger a reload β a false positive.)
Wait, I confused myself. Let me redo Option B precisely:
Option B rule: render only if `ev.seq == lastSeq + 1` (or lastSeq==0 β accept the first). Otherwise β reload.
- Fresh page: the first replayed event is accepted at any seq; the buffer is contiguous β all render. β
- Reconnect, in sync (S==L), buffer replays duplicates (seq β€ L): the first replayed event's seq B0 β€ L < L+1 β reload. False positive (unnecessary reload). β (but safe)
- Reconnect, the buffer heals (the buffer has L+1..S): the first replayed event's seq L+1 == lastSeq+1 β render! Then L+2, β¦ contiguous β healed, no reload. β
- Reconnect, the buffer was checkpointed (empty or starts above L+1): resync S > Lβ¦ wait, under Option B, does the client act on resync? If the buffer is empty: no replayed events; the next live event is S+1 > L+1 β jump β reload. β (delayed by one event) β or the resync marker triggers it immediately. β
- Drops in the middle that are hidden by later contiguous events: undetectable (both A and B). β (rare; requires a precise drop pattern where the client keeps up after the drop)
Option B's false positive (reconnect with a duplicate replay β reload): how bad? A reload is a brief flicker, the static view is complete, and the subscription resumes. For a single-user local dashboard: acceptable. And it's safe.
Option A's silent loss (dropped in the middle, caught up later, then a duplicate replay is skipped): the user sees a permanently wrong block. That's the reported bug. β
So Option B (strict contiguity, reload on any anomaly) is the safer choice. The cost is an occasional unnecessary reload on reconnect. I'm comfortable with that.
Hmm, wait β but actually, let me reconsider whether the "duplicate replay" false positive is really that common. Reconnect scenarios:
1. Network blip mid-run: the buffer is almost certainly non-empty (a block is in progress β the run is active). The client was mid-block. On reconnect: the buffer replays from the last checkpoint β which includes events the client already rendered (from the checkpoint to L) plus the in-flight ones (L+1..S). The first replayed event: seq = (last checkpoint seq + 1) β€ L β reload. So yes, a common false positive in this scenario.
2. Server restart: the hub is in-memory β all state lost. The client reconnects: a new hub entry, seq 0, empty buffer. The first event has seq 1. The client's lastSeq=L>0 β 1 != L+1 β reload. β Correct (after a server restart, the live state is gone anyway; the static view from the store is the truth β wait, is it? The store is on disk (SQLite) β yes, the persisted blocks survive a server restart. The in-flight un-persisted block is lost β it vanishes from the log. Hmm, that's an existing data-loss issue on server restart, out of scope.)
OK, so under Option B, scenario 1 (the most common reconnect) always reloads. The user sees a flicker on every network blip. Hmm. For a local dashboard (localhost!), network blips are rare (it's a loopback connection!). The main drop scenarios for a local dashboard: a background tab (throttled JS) or a busy browser. On loopback, the TCP buffer is large and the connection doesn't drop β events just pile up in the channel β drops β the client receives a burst with jumps β detected by the strict rule. β No reload needed in that case β wait:
Background tab scenario: the channel fills (256), events are dropped, the tab wakes up, the browser drains the channel: the client receives a burst. The first event of the burst has a seq jump (lastSeq+1 was dropped) β reload. β Detected!
But hmm β one more: the browser's own SSE queue. The server writes to the TCP socket; the browser buffers it. If the server's channel doesn't overflow (the browser reads fast enough), no drops. The browser's queue is large. Drops require the server's 256 channel to overflow, i.e. the browser not reading for a while (a throttled tab, a sleep, a stall). OK.
So Option B detects the realistic drop scenarios.
Now, let me also reconsider: do we really need the resync marker under Option B? The resync marker handles: reconnect with an empty buffer + S > L (the client is behind, nothing to replay). Without the marker: the client waits; the next event (S+1) triggers a jump β reload. Delay = time until the next event. During a long tool call (bash can run for minutes), the user sees a stale open block for minutes. With the marker: immediate reload. The marker is cheap (one extra SSE line + a few lines of client code). Let's keep it.
Actually hmm, wait β under Option B, the resync handler: `if (lastSeq !== 0 && (typeof ev.seq !== "number" || ev.seq !== lastSeq)) resyncWithStatic();` β S > L β reload β; S == L β no reload (in sync; the replay, if any, is handled by the strict rule: duplicate β reload (false positive) or contiguous β heal). Hmm wait, if S == L and the buffer has duplicates, the strict rule reloads on the first duplicate. So the resync's S==L "no reload" is overridden by the replay's duplicate β reload. Consistent (safe).
And S < L (impossible in practice): reload (safe).
OK β final design, Option B + resync marker:
**Client rules:**
1. `resync` event: if lastSeq !== 0 and ev.seq !== lastSeq (or missing) β reload. (A (re)connect where the hub is at a different position than where we left off β the replay can't be trusted to heal usβ¦ wait, no! If S > L and the buffer heals (contains L+1..S), we can heal without a reload! But the resync marker says S > L β reload. False positive again!
Ugh. OK, the point is: the resync marker can't distinguish "the buffer heals" from "the buffer was checkpointed" β it only knows S. To avoid the false positive, the resync should not trigger a reload when S > L; it should let the replay decide. The resync only helps when the buffer is empty (nothing to replay): in that case, S > L β definite gap β reload.
So: the resync event should carry both the current seq and whether the buffer is emptyβ¦ or: the server only sends resync when the buffer is empty! If the buffer is non-empty, the replay itself provides the contiguity check (the first replayed event: contiguous β heal; duplicate β reload; gap β reload). If the buffer is empty, send resync(S): the client compares with lastSeq: S == L β in sync; S > L β gap β reload.
That's clean! The server:
```go
buffered, seq, ch, cancel := s.hub.Subscribe(id)
defer cancel()
write := ...
// If there's nothing to replay, tell the client where the hub is at:
// if it's ahead of what the client last rendered, the client missed
// events that are no longer replayable and must fall back to the
// static page. (If there is something to replay, the replayed events'
// sequence numbers provide the same check: the client renders them if
// they're contiguous with what it has, and reloads otherwise.)
if len(buffered) == 0 {
if !write(livelog.Event{Type: livelog.Resync, Seq: seq}) {
return
}
}
for _, ev := range buffered { ... }
```
**Client rules (final):**
```js
if (ev.type === "resync") {
// No buffered events to replay; the hub is at seq ev.seq. If we
// last rendered something else, we missed events β static page.
if (lastSeq !== 0 && (typeof ev.seq !== "number" || ev.seq !== lastSeq)) {
resyncWithStatic();
}
return;
}
if (typeof ev.seq === "number") {
if (lastSeq === 0) {
lastSeq = ev.seq; // first event (fresh page, or joining mid-replay)
} else if (ev.seq === lastSeq + 1) {
lastSeq = ev.seq; // contiguous: render
} else {
// Replay of an already-rendered event, or a gap (dropped
// events): either way the live view can't be trusted.
resyncWithStatic();
return;
}
}
```
Wait β `lastSeq === 0` β accept the first event at any seq. Fresh page joining mid-replay: the buffer is contiguous from the checkpoint; the first event is accepted; the rest are contiguous. β But what if a fresh page's first event is a duplicate?? A fresh page has lastSeq=0 β it has rendered nothing. There are no duplicates for it. β
Hmm, one more: a fresh page, the buffer is empty, the first live event is accepted at seq S. β
And the "dropped in the middle, hidden" case: undetectable (accepted). As established, this is an acceptable residual risk (it requires a drop burst followed by the client catching up and staying contiguous β and even then, the next reconnect with a non-empty buffer triggers a reload via the duplicate checkβ¦ no wait: on reconnect, the buffer replays duplicates β the first replayed event's seq β€ L β not L+1 β reload. β Healed on the next reconnect! And if the buffer is checkpointed β the resync (empty buffer) S > Lβ¦ wait, S is the current seq, L is the client's lastSeq: S β₯ L; if S > L β reload β; if S == L β the loss persists (the hub is at exactly L β no new events β the loss is hidden forever until a new event: the next event L+1 is contiguous β render β still hidden. Ugh.)
OK, the point is: the "dropped in the middle, hidden, then checkpointed at exactly L" case is a corner of a corner. The realistic drop scenarios (the channel overflows and the client falls behind) produce visible jumps β detected. I'm satisfied.
Actually, hmm, wait. Let me reconsider the "channel overflows and the client falls behind" scenario under the final rules. The client is throttled (background tab). The channel overflows: events are dropped. The tab wakes up. The browser drains the channel: the client receives a burst. The first event of the burst: its seq vs lastSeq+1. If the dropped events were exactlyβ¦ no β the dropped events are the ones that couldn't be sent; the events after them were sent (if the channel had room again). So the burst starts at a seq > lastSeq+1 (a jump) β reload. β
But: what if the channel overflowed and the client was throttled, and the run ended in the meantime? hub.Close β the channel is closed (the remaining buffered events in the channel are still readable! closing a channel doesn't discard its buffer). The client drains: the burst, then the channel closes β the handler returns β the SSE stream ends β EventSource reconnects β the job is complete β an empty 200 β the ES keeps failing/retryingβ¦ and the client's lastSeq is stale. Hmm β but the burst: the client processes the burst's events: jump β reload β (if there was a jump) or contiguous (if the drops aligned perfectly β unlikely) β then the channel closes, the stream ends, the ES reconnects, gets an empty response, retries forever. The page shows "running" (stale header) with the blocks. The user manually reloads. Existing behavior (documented in the render() comment: "the automatic location.reload() the job's SSE stream triggers on completion"). No problem β out of scope.
OK. Now β one more design question: should `resyncWithStatic` be used for the `status` case too? The status case: `es.close(); location.reload()` β same thing. We can reuse it. Let me use `resyncWithStatic()` for both (rename it to `reloadStatic()`? The name "resync" is overloaded with the event typeβ¦ let me call it `fallBackToStatic()` or just keep the inline `es.close(); location.reload()` for status. Hmm, let me define one helper `function resyncPage() { es.close(); location.reload(); }` and use it everywhere. Actually, the existing code for status is inline; let me keep the diff small and readable: define the helper and use it in both places.
Now, the server-side `write` for resync: `livelog.Event{Type: livelog.Resync, Seq: seq}` β JSON `{"type":"resync","seq":N}` (seq is omitted if 0). The client: `typeof ev.seq !== "number"` β treat as a mismatch when lastSeq !== 0 β reload. When would the server send a resync with seq 0? A new hub entry (no events yet) with an empty buffer. A reconnecting client with lastSeq>0 β the hub entry was recreated β reload β. A fresh page with lastSeq=0 β no-op β.
Now β the `Event.Seq` field with `omitempty`: the status event has a seq (published via Publish). Tool events have a seq. β All published events have a seq. Only the server-synthesized resync can lack one (seq 0).
Now, let's also update the hub's doc comment about drops:
```go
// subChanBuffer bounds how many events a slow subscriber can lag behind
// by before new events are dropped for it. Generous for a single-user
// local dashboard. A dropped event is recoverable, not silent: every
// event carries a monotonically increasing Seq (see Event.Seq), so a
// client that misses one detects the gap in the sequence and falls
// back to the static page, which is always complete.
```
And the `Subscribe` doc: mention that it returns the current seq.
Now, the tests.
**hub_test.go** β update the Subscribe calls (new signature) and add:
```go
func TestPublishAssignsMonotonicSeq(t *testing.T) {
h := NewHub()
h.Publish("job-1", Event{Type: ContentStart})
h.Publish("job-1", Event{Type: ContentDelta, Text: "hi"})
h.Publish("job-2", Event{Type: ContentStart})
buffered, seq, cancel := h.Subscribe("job-1")
defer cancel()
if seq != 2 {
t.Fatalf("expected current seq 2, got %d", seq)
}
for i, ev := range buffered {
if ev.Seq != uint64(i+1) {
t.Fatalf("expected seq %d at index %d, got %+v", i+1, i, ev)
}
}
// Seqs are per-job: job-2's stream is independent.
buffered2, seq2, cancel2 := h.Subscribe("job-2")
defer cancel2()
if seq2 != 1 || len(buffered2) != 1 || buffered2[0].Seq != 1 {
t.Fatalf("expected job-2 to have its own seq space, got seq=%d buffered=%+v", seq2, buffered2)
}
}
func TestSubscribeSeqTracksLatestPublished(t *testing.T) {
h := NewHub()
_, seq, cancel := h.Subscribe("job-1")
defer cancel()
if seq != 0 {
t.Fatalf("expected seq 0 for a fresh job, got %d", seq)
}
h.Publish("job-1", Event{Type: ContentDelta, Text: "hi"})
_, seq, _ = h.Subscribe("job-1")
if seq != 1 {
t.Fatalf("expected seq 1 after one publish, got %d", seq)
}
}
```
Hmm wait, the existing tests call `h.Subscribe` with 3 return values; now it's 4. Update them all.
**web_test.go** β add a test that the SSE stream starts with a resync when the buffer is empty, and that events carry a contiguous seq:
```go
// TestJobEventsSequenceNumbers verifies the SSE stream numbers every
// event (per job, monotonically) and opens with a resync marker when
// there's nothing to replay, so a client can detect dropped events and
// fall back to the static page (issue #60).
func TestJobEventsSequenceNumbers(t *testing.T) {
s, st := testServer(t)
ctx := context.Background()
if err := st.CreateJob(ctx, store.Job{ID: "job-1", EventKind: "issue:new", Agent: "leon", Owner: "acme", Repo: "widgets", IssueIndex: 1}); err != nil {
t.Fatal(err)
}
// Nothing buffered: the stream must open with a resync carrying the
// hub's current seq (0 for a fresh job).
evCtx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
defer cancel()
rr := httptest.NewRecorder()
s.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/jobs/job-1/events", nil).WithContext(evCtx))
body := rr.Body.String()
if !strings.HasPrefix(body, `data: {"type":"resync"}`) {
t.Fatalf("expected stream to open with a resync marker, got: %s", body)
}
// Now publish a block: a new subscriber gets the buffered events,
// numbered contiguously from 1.
s.hub.Publish("job-1", livelog.Event{Type: livelog.ContentStart})
s.hub.Publish("job-1", livelog.Event{Type: livelog.ContentDelta, Text: "hi"})
evCtx2, cancel2 := context.WithTimeout(context.Background(), 100*time.Millisecond)
defer cancel2()
rr = httptest.NewRecorder()
s.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/jobs/job-1/events", nil).WithContext(evCtx2))
body = rr.Body.String()
if !strings.Contains(body, `"seq":1`) || !strings.Contains(body, `"seq":2`) {
t.Fatalf("expected contiguous seqs 1 and 2, got: %s", body)
}
// With a non-empty buffer there's no resync marker: the replayed
// events' seqs are the continuity check.
if strings.Contains(body, `"resync"`) {
t.Fatalf("did not expect a resync marker with a non-empty buffer, got: %s", body)
}
}
```
Hmm wait β the JSON field order: Go marshals struct fields in declaration order: Type, Seq, Text, β¦ β `{"type":"resync"}` (seq 0 is omitted) β; `{"type":"content_start","seq":1}` β; `{"type":"content_delta","seq":2,"text":"hi"}` β.
Note: the first request (empty buffer) β the handler writes the resync, then blocks until the context times out (100ms). The body = `data: {"type":"resync"}\n\n`. β
Now, the JS changes in templates.go. Let me write the full replacement for the script block. The current script (from the file):
```js
(function() {
var jobID = {{.Job.ID}};
var log = document.getElementById("log");
var reasoningBody = null;
var contentBody = null;
function nearBottom() {
return (window.innerHeight + window.scrollY) >= (document.body.offsetHeight - 80);
}
function newBlock(kind, label) {
var div = document.createElement("div");
div.className = "block block-" + kind;
if (label) {
var l = document.createElement("div");
l.className = "block-label";
l.textContent = label;
div.appendChild(l);
}
var body = document.createElement("div");
body.className = "block-body";
div.appendChild(body);
log.appendChild(div);
return body;
}
function newToolBlock(ev) { ... }
var es = new EventSource("/jobs/" + jobID + "/events");
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
var shouldScroll = nearBottom();
switch (ev.type) {
case "reasoning_start":
reasoningBody = newBlock("reasoning", "Thinking");
break;
case "reasoning_delta":
if (reasoningBody) reasoningBody.textContent += ev.text;
break;
case "reasoning_end":
// Model output routinely starts/ends with newlines; drop them
// so the finished block matches the static (trimmed) view.
if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();
reasoningBody = null;
break;
case "content_start":
contentBody = newBlock("content", null);
break;
case "content_delta":
if (contentBody) contentBody.textContent += ev.text;
break;
case "content_end":
if (contentBody) contentBody.textContent = contentBody.textContent.trim();
contentBody = null;
break;
case "tool":
newToolBlock(ev);
break;
case "status":
es.close();
location.reload();
return;
}
if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);
};
})();
```
New version:
```js
(function() {
var jobID = {{.Job.ID}};
var log = document.getElementById("log");
// Per-block-kind rendering state: the open block's body (null
// while none is open) and a buffer of deltas received before the
// block was created. Model output routinely starts with
// newlines, and a block that ends up whitespace-only must not
// render at all (the static view drops those blocks too), so a
// block is created lazily on its first non-whitespace text
// instead of on the *_start event β that's what keeps a
// whitespace-only turn from flashing an empty block shell
// (issue #60).
var blocks = {
reasoning: {body: null, buf: ""},
content: {body: null, buf: ""}
};
// lastSeq is the sequence number of the last event rendered. The
// server numbers every event per job and sends a "resync" marker
// (with the hub's current number) when a subscription starts with
// nothing to replay. Any break in the sequence β a gap from
// dropped events, or a replay we already rendered β means the
// block state above can no longer be trusted, so we fall back to
// the static page, which is always complete.
var lastSeq = 0;
var es = new EventSource("/jobs/" + jobID + "/events");
function resyncPage() {
es.close();
location.reload();
}
function nearBottom() {
return (window.innerHeight + window.scrollY) >= (document.body.offsetHeight - 80);
}
function newBlock(kind, label) {
var div = document.createElement("div");
div.className = "block block-" + kind;
if (label) {
var l = document.createElement("div");
l.className = "block-label";
l.textContent = label;
div.appendChild(l);
}
var body = document.createElement("div");
body.className = "block-body";
div.appendChild(body);
log.appendChild(div);
return body;
}
function newToolBlock(ev) { ... unchanged ... }
function onDelta(kind, delta) {
var b = blocks[kind];
if (b.body) {
b.body.textContent += delta;
return;
}
b.buf += delta;
if (b.buf.trim() === "") return; // whitespace so far: no block yet
b.body = newBlock(kind, kind === "reasoning" ? "Thinking" : null);
b.body.textContent = b.buf;
b.buf = "";
}
function onEnd(kind) {
var b = blocks[kind];
if (b.body) {
// Model output routinely starts/ends with newlines; drop them
// so the finished block matches the static (trimmed) view,
// and drop the block entirely if nothing is left.
b.body.textContent = b.body.textContent.trim();
if (b.body.textContent === "") b.body.parentElement.remove();
b.body = null;
}
b.buf = "";
}
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
if (ev.type === "resync") {
// The subscription started with nothing to replay, and the
// hub is at seq ev.seq. If we last rendered something else,
// we missed events that are no longer replayable.
if (lastSeq !== 0 && (typeof ev.seq !== "number" || ev.seq !== lastSeq)) {
resyncPage();
}
return;
}
if (typeof ev.seq === "number") {
if (lastSeq === 0) {
lastSeq = ev.seq; // first event: fresh page, or joining a replay
} else if (ev.seq === lastSeq + 1) {
lastSeq = ev.seq; // contiguous: render
} else {
resyncPage(); // gap (dropped events) or duplicate replay
return;
}
}
var shouldScroll = nearBottom();
switch (ev.type) {
case "reasoning_start":
blocks.reasoning.body = null;
blocks.reasoning.buf = "";
break;
case "reasoning_delta":
onDelta("reasoning", ev.text);
break;
case "reasoning_end":
onEnd("reasoning");
break;
case "content_start":
blocks.content.body = null;
blocks.content.buf = "";
break;
case "content_delta":
onDelta("content", ev.text);
break;
case "content_end":
onEnd("content");
break;
case "tool":
newToolBlock(ev);
break;
case "status":
resyncPage();
return;
}
if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);
};
})();
```
Wait, there's an ordering issue: `resyncPage` references `es`, which is declared with `var es = ...` before the function definition β no problem (the function is called later). But I placed `var es = new EventSource(...)` before the function definitions β the original code had `var es` after newToolBlock. The order doesn't matter for the correctness of the function declarations (hoisting). Let me keep a sensible order: state variables, es, functions, onmessage.
Hmm, one more consideration: `b.body.parentElement.remove()` β `parentElement` is the block div (`.block`). β (The body div's parent is the block div.)
Now β a subtle issue with `onDelta` when the block exists and a delta arrives: `b.body.textContent += delta`. If the block was created with a buf that had leading whitespace (e.g. "\n\nHello"), the body's text = "\n\nHello", then deltas are appended. On end: trim β "Hello..." β matches the static view (buildBlocks trims the whole line). β
Another subtle point: `reasoning_start`/`content_start` reset the state (body=null, buf=""). When would a start arrive while a block is open? Only if the previous end was dropped β but in that case, the seq check should have reloaded the page first (the start's seq is a jump, orβ¦ hmm: if the end was dropped and everything else was received: the client has lastSeq = end.seq - 1β¦ no wait: the events are start(10), delta(11), end(12). The client receives 10, 11, drops 12, then the next turn's start(13): 13 == 12+1? No β the client's lastSeq=11, 13 != 12 β jump β reload β. If the end was dropped and the next start was also dropped: start(14)β¦ the client sees 14 != 12 β reload β. If the end was dropped and the next turn has no events (a tool-only turn): the tool event(13): 13 != 12 β reload β. Good β the seq check catches all of these before the state machine sees the anomalous start. And the reset on start is just defensive (in case the server ever sends a start while a block is openβ¦ which can't happen β streamHooks closes the block in OnTurnEnd before the next turn's start; and the seq check guards the client).
Hmm wait, actually β can a `content_start` arrive while the client's block is open in a legitimate case? The server publishes content_start only when contentOpen is false (it was closed in OnTurnEnd). The client's block is open only if it missed the end β the seq jump β reload. So no. The reset is defensive. β
Now, one more: the `shouldScroll` for the resync case β we return before it. β No DOM change on resync.
Now, let me also double-check the interaction of the lazy creation with the replay buffer for a fresh page: the buffer = [content_start(10), content_delta(11, "\n"), content_delta(12, "Hello")]. The client: start β reset. delta(11): buf="\n", trim="" β no block. delta(12): buf="\nHello", trim="Hello" β create the block with text "\nHello". β The block shows a blank line, then "Hello" β then on end it's trimmed. β
And a whitespace-only turn: [content_start(10), content_delta(11, "\n"), content_end(12)]: no block is ever created. β No empty shell. ββ
Now, the static view: buildBlocks already handles it (drops whitespace-only). β Consistent.
Now, let me write the code. Also update the package doc comment in hub.go? The package doc says "It carries only the tail of a run that hasn't made it into SQLite yet β see Hub.Checkpoint." No problem, no change needed.
One more check β are there other callers of `Subscribe` or constructors of `livelog.Event`? Let me grep.
Baseline is green. Now let me check all usages of the hub's `Subscribe` and `Event` to plan the change:
Tool
π§ grep_search
{"context_after": 2, "context_before": 2, "query": "\\.Subscribe\\(|livelog\\.Event\\{"}
Arguments
{"context_after": 2, "context_before": 2, "query": "\\.Subscribe\\(|livelog\\.Event\\{"}
Result
/project/internal/web/web_test.go-78- // hub (not yet checkpointed/persisted) and then wait for more, until
/project/internal/web/web_test.go-79- // the request context is done.
/project/internal/web/web_test.go:80: s.hub.Publish("job-1", livelog.Event{Type: livelog.ContentDelta, Text: "streaming"})
/project/internal/web/web_test.go-81-
/project/internal/web/web_test.go-82- evCtx, cancel := context.WithTimeout(context.Background(), 200*time.Millisecond)
--
/project/internal/web/web.go-303- w.WriteHeader(http.StatusOK)
/project/internal/web/web.go-304-
/project/internal/web/web.go:305: buffered, ch, cancel := s.hub.Subscribe(id)
/project/internal/web/web.go-306- defer cancel()
/project/internal/web/web.go-307-
--
/project/internal/livelog/hub_test.go-29- h.Publish("job-1", Event{Type: ContentDelta, Text: "hi"})
/project/internal/livelog/hub_test.go-30-
/project/internal/livelog/hub_test.go:31: buffered, ch, cancel := h.Subscribe("job-1")
/project/internal/livelog/hub_test.go-32- defer cancel()
/project/internal/livelog/hub_test.go-33-
--
/project/internal/livelog/hub_test.go-54- h.Checkpoint("job-1")
/project/internal/livelog/hub_test.go-55-
/project/internal/livelog/hub_test.go:56: buffered, _, cancel := h.Subscribe("job-1")
/project/internal/livelog/hub_test.go-57- defer cancel()
/project/internal/livelog/hub_test.go-58-
--
/project/internal/livelog/hub_test.go-65- h := NewHub()
/project/internal/livelog/hub_test.go-66-
/project/internal/livelog/hub_test.go:67: _, ch, cancel := h.Subscribe("job-1")
/project/internal/livelog/hub_test.go-68- defer cancel()
/project/internal/livelog/hub_test.go-69-
--
/project/internal/livelog/hub_test.go-91- h.Close("job-1")
/project/internal/livelog/hub_test.go-92-
/project/internal/livelog/hub_test.go:93: buffered, ch, cancel := h.Subscribe("job-1")
/project/internal/livelog/hub_test.go-94- defer cancel()
/project/internal/livelog/hub_test.go-95-
--
/project/internal/livelog/hub_test.go-108- h := NewHub()
/project/internal/livelog/hub_test.go-109-
/project/internal/livelog/hub_test.go:110: _, ch, cancel := h.Subscribe("job-1")
/project/internal/livelog/hub_test.go-111- cancel()
/project/internal/livelog/hub_test.go-112-
--
/project/internal/agentrun/run.go-296- reasoningOpen = true
/project/internal/agentrun/run.go-297- reasoningBuf.Reset()
/project/internal/agentrun/run.go:298: r.hub.Publish(jobID, livelog.Event{Type: livelog.ReasoningStart})
/project/internal/agentrun/run.go-299- }
/project/internal/agentrun/run.go-300-
/project/internal/agentrun/run.go-301- reasoningBuf.WriteString(delta)
/project/internal/agentrun/run.go:302: r.hub.Publish(jobID, livelog.Event{Type: livelog.ReasoningDelta, Text: delta})
/project/internal/agentrun/run.go-303- },
/project/internal/agentrun/run.go-304- OnContentDelta: func(delta string) {
--
/project/internal/agentrun/run.go-306- contentOpen = true
/project/internal/agentrun/run.go-307- contentBuf.Reset()
/project/internal/agentrun/run.go:308: r.hub.Publish(jobID, livelog.Event{Type: livelog.ContentStart})
/project/internal/agentrun/run.go-309- }
/project/internal/agentrun/run.go-310-
/project/internal/agentrun/run.go-311- contentBuf.WriteString(delta)
/project/internal/agentrun/run.go:312: r.hub.Publish(jobID, livelog.Event{Type: livelog.ContentDelta, Text: delta})
/project/internal/agentrun/run.go-313- },
/project/internal/agentrun/run.go-314- OnTurnEnd: func() {
/project/internal/agentrun/run.go-315- if reasoningOpen {
/project/internal/agentrun/run.go:316: r.hub.Publish(jobID, livelog.Event{Type: livelog.ReasoningEnd})
/project/internal/agentrun/run.go-317- logAppend("reasoning", reasoningBuf.String())
/project/internal/agentrun/run.go-318- r.hub.Checkpoint(jobID)
--
/project/internal/agentrun/run.go-321-
/project/internal/agentrun/run.go-322- if contentOpen {
/project/internal/agentrun/run.go:323: r.hub.Publish(jobID, livelog.Event{Type: livelog.ContentEnd})
/project/internal/agentrun/run.go-324- logAppend("content", contentBuf.String())
/project/internal/agentrun/run.go-325- r.hub.Checkpoint(jobID)
--
/project/internal/agentrun/run.go-328- },
/project/internal/agentrun/run.go-329- OnTool: func(name, arguments, result string, toolErr bool) {
/project/internal/agentrun/run.go:330: r.hub.Publish(jobID, livelog.Event{
/project/internal/agentrun/run.go-331- Type: livelog.Tool,
/project/internal/agentrun/run.go-332- Name: name,
Thinking
Alright β the only place using `Subscribe` is web.go, and the tests. Now I have the full picture. Let me write up the analysis and implement it.
## Diagnosis
The empty `block-body` is a **live (SSE) view** artifact (the empty example in the issue has no indentation β it's a DOM node created by JS, not the static template. The static template renders `block-body` with indentation, and `buildBlocks` already excludes whitespace-only blocks).
Two root causes:
1. **Whitespace-only model output β empty block shell.** The live JS creates a block on `content_start`/`reasoning_start`, and on `*_end` trims the accumulated text. When the model emits a message whose content is only whitespace (e.g. `"\n"` β common when a message is mostly tool calls), the block is left as an empty shell. The static view excludes such blocks, so the shell disappears on reload β which is why the reporter couldn't reproduce it in old logs.
2. **Dropped SSE events desync the live view.** `livelog.Hub` intentionally drops events for slow subscribers (256-slot channel full β background tab, network stall, laptop sleep). The client's start/delta/end state machine cannot recover from a gap:
- dropped `*_delta` β empty or truncated block ("there should be some text in there");
- dropped `*_end` β untrimmed block (extra vertical space β the issue's second example) and the next `*_start` orphans it.
## Fix
1. **JS**: lazily create reasoning/content blocks on the first *non-whitespace* delta; on `*_end`, trim and remove the block if empty. Whitespace-only turns no longer produce an empty shell at all.
2. **Sequence numbers**: every hub event gets a per-job monotonically increasing `Seq`; the SSE handler sends a `resync` marker (with the hub's current seq) when a subscription starts with an empty replay buffer; the client enforces strict contiguity β on any gap or duplicate replay, it falls back to the static page (which is always complete) via reload.
Now let me implement. Starting with hub.go.
I now have the complete picture. Let me document my diagnosis before implementing:
**Diagnosis** β the empty `block-body` is a **live (SSE) view** artifact (the issue's empty example is unindented JS-created DOM, not the static template; the static view's `buildBlocks` already drops whitespace-only blocks). Two root causes:
1. **Whitespace-only model output β empty block shell.** The live JS creates a block on `content_start`, then trims to `""` on `content_end`. When the model emits a message whose content is only whitespace (e.g. `"\n"` β common when a message is mostly tool calls), an empty shell is left in the DOM. The static view drops such blocks, so the shell vanishes on reload β matching "maybe just when streaming".
2. **Dropped SSE events desync the live view.** `livelog.Hub` deliberately drops events for slow subscribers (full 256-slot channel β background tab, network stall). The client's start/delta/end state machine can't recover: dropped deltas β empty/truncated block ("there should be some text in there"); dropped `*_end` β untrimmed block with excess vertical space (the issue's second example).
The fix: lazy block creation (no shell for whitespace-only turns), plus per-job event sequence numbers with a `resync` marker so the client detects any gap and falls back to the static page (the source of truth). Let me implement, starting with the hub:
Tool
π§ edit_file
{"find": "type Type string\n\nconst (\n\tReasoningStart Type = \"reasoning_start\"\n\tReasoningDelta Type = \"reasoning_delta\"\n\tReasoningEnd Type = \"reasoning_end\"\n\tContentStart Type = \"content_start\"\n\tContentDelta Type = \"content_delta\"\n\tContentEnd Type = \"content_end\"\n\tTool Type = \"tool\"\n\tStatus Type = \"status\"\n)\n\ntype Event struct {\n\tType Type `json:\"type\"`\n\tText string `json:\"text,omitempty\"`\n\tName string `json:\"name,omitempty\"`\n\tArguments string `json:\"arguments,omitempty\"`\n\tResult string `json:\"result,omitempty\"`\n\tError bool `json:\"error,omitempty\"`\n\tStatus string `json:\"status,omitempty\"`\n}\n\n// subChanBuffer bounds how many events a slow subscriber can lag behind\n// by before new events are dropped for it. Generous for a single-user\n// local dashboard; a dropped event just means a subscriber's browser\n// tab misses a chunk and catches up on the next one, never a hang.\nconst subChanBuffer = 256", "path": "internal/livelog/hub.go", "replace": "type Type string\n\nconst (\n\tReasoningStart Type = \"reasoning_start\"\n\tReasoningDelta Type = \"reasoning_delta\"\n\tReasoningEnd Type = \"reasoning_end\"\n\tContentStart Type = \"content_start\"\n\tContentDelta Type = \"content_delta\"\n\tContentEnd Type = \"content_end\"\n\tTool Type = \"tool\"\n\tStatus Type = \"status\"\n\n\t// Resync is never published through Publish; the web layer sends it\n\t// as the first message of a subscription that starts with an empty\n\t// replay buffer, carrying the job's current sequence number, so the\n\t// client can tell whether it missed events since its last\n\t// (re)connect.\n\tResync Type = \"resync\"\n)\n\ntype Event struct {\n\tType Type `json:\"type\"`\n\t// Seq is the job's monotonically increasing sequence number,\n\t// assigned by Publish. Clients use it to detect dropped events\n\t// (gaps in the sequence) and fall back to the static page, which\n\t// is always complete.\n\tSeq uint64 `json:\"seq,omitempty\"`\n\tText string `json:\"text,omitempty\"`\n\tName string `json:\"name,omitempty\"`\n\tArguments string `json:\"arguments,omitempty\"`\n\tResult string `json:\"result,omitempty\"`\n\tError bool `json:\"error,omitempty\"`\n\tStatus string `json:\"status,omitempty\"`\n}\n\n// subChanBuffer bounds how many events a slow subscriber can lag behind\n// by before new events are dropped for it. Generous for a single-user\n// local dashboard. A dropped event is recoverable rather than silent:\n// every event carries a monotonically increasing Seq, so a client that\n// misses one detects the gap in the sequence and falls back to the\n// static page instead of rendering a desynced (empty or truncated)\n// block.\nconst subChanBuffer = 256"}
Arguments
{"find": "type Type string\n\nconst (\n\tReasoningStart Type = \"reasoning_start\"\n\tReasoningDelta Type = \"reasoning_delta\"\n\tReasoningEnd Type = \"reasoning_end\"\n\tContentStart Type = \"content_start\"\n\tContentDelta Type = \"content_delta\"\n\tContentEnd Type = \"content_end\"\n\tTool Type = \"tool\"\n\tStatus Type = \"status\"\n)\n\ntype Event struct {\n\tType Type `json:\"type\"`\n\tText string `json:\"text,omitempty\"`\n\tName string `json:\"name,omitempty\"`\n\tArguments string `json:\"arguments,omitempty\"`\n\tResult string `json:\"result,omitempty\"`\n\tError bool `json:\"error,omitempty\"`\n\tStatus string `json:\"status,omitempty\"`\n}\n\n// subChanBuffer bounds how many events a slow subscriber can lag behind\n// by before new events are dropped for it. Generous for a single-user\n// local dashboard; a dropped event just means a subscriber's browser\n// tab misses a chunk and catches up on the next one, never a hang.\nconst subChanBuffer = 256", "path": "internal/livelog/hub.go", "replace": "type Type string\n\nconst (\n\tReasoningStart Type = \"reasoning_start\"\n\tReasoningDelta Type = \"reasoning_delta\"\n\tReasoningEnd Type = \"reasoning_end\"\n\tContentStart Type = \"content_start\"\n\tContentDelta Type = \"content_delta\"\n\tContentEnd Type = \"content_end\"\n\tTool Type = \"tool\"\n\tStatus Type = \"status\"\n\n\t// Resync is never published through Publish; the web layer sends it\n\t// as the first message of a subscription that starts with an empty\n\t// replay buffer, carrying the job's current sequence number, so the\n\t// client can tell whether it missed events since its last\n\t// (re)connect.\n\tResync Type = \"resync\"\n)\n\ntype Event struct {\n\tType Type `json:\"type\"`\n\t// Seq is the job's monotonically increasing sequence number,\n\t// assigned by Publish. Clients use it to detect dropped events\n\t// (gaps in the sequence) and fall back to the static page, which\n\t// is always complete.\n\tSeq uint64 `json:\"seq,omitempty\"`\n\tText string `json:\"text,omitempty\"`\n\tName string `json:\"name,omitempty\"`\n\tArguments string `json:\"arguments,omitempty\"`\n\tResult string `json:\"result,omitempty\"`\n\tError bool `json:\"error,omitempty\"`\n\tStatus string `json:\"status,omitempty\"`\n}\n\n// subChanBuffer bounds how many events a slow subscriber can lag behind\n// by before new events are dropped for it. Generous for a single-user\n// local dashboard. A dropped event is recoverable rather than silent:\n// every event carries a monotonically increasing Seq, so a client that\n// misses one detects the gap in the sequence and falls back to the\n// static page instead of rendering a desynced (empty or truncated)\n// block.\nconst subChanBuffer = 256"}
Result
1 occurrences replaced
Thinking
Next, I'll update the stream struct, Publish, and Subscribe.
Tool
π§ edit_file
{"find": "type stream struct {\n\tmu sync.Mutex\n\tbuf []Event\n\tsubs map[chan Event]struct{}\n}", "path": "internal/livelog/hub.go", "replace": "type stream struct {\n\tmu sync.Mutex\n\tbuf []Event\n\tsubs map[chan Event]struct{}\n\tseq uint64\n}"}
Arguments
{"find": "type stream struct {\n\tmu sync.Mutex\n\tbuf []Event\n\tsubs map[chan Event]struct{}\n}", "path": "internal/livelog/hub.go", "replace": "type stream struct {\n\tmu sync.Mutex\n\tbuf []Event\n\tsubs map[chan Event]struct{}\n\tseq uint64\n}"}
Result
1 occurrences replaced
Tool
π§ edit_file
{"find": "// Publish appends ev to jobID's replay buffer and fans it out to every\n// current subscriber. Never blocks: a subscriber whose channel is full\n// simply misses this event.\nfunc (h *Hub) Publish(jobID string, ev Event) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\ts.buf = append(s.buf, ev)", "path": "internal/livelog/hub.go", "replace": "// Publish appends ev to jobID's replay buffer and fans it out to every\n// current subscriber. Never blocks: a subscriber whose channel is full\n// simply misses this event (the client detects the resulting gap in\n// Seq and falls back to the static page).\nfunc (h *Hub) Publish(jobID string, ev Event) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\ts.seq++\n\tev.Seq = s.seq\n\n\ts.buf = append(s.buf, ev)"}
Arguments
{"find": "// Publish appends ev to jobID's replay buffer and fans it out to every\n// current subscriber. Never blocks: a subscriber whose channel is full\n// simply misses this event.\nfunc (h *Hub) Publish(jobID string, ev Event) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\ts.buf = append(s.buf, ev)", "path": "internal/livelog/hub.go", "replace": "// Publish appends ev to jobID's replay buffer and fans it out to every\n// current subscriber. Never blocks: a subscriber whose channel is full\n// simply misses this event (the client detects the resulting gap in\n// Seq and falls back to the static page).\nfunc (h *Hub) Publish(jobID string, ev Event) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\ts.seq++\n\tev.Seq = s.seq\n\n\ts.buf = append(s.buf, ev)"}
Result
1 occurrences replaced
Thinking
Next, about the `Subscribe` method β it returns the current sequence number atomically together with the buffer snapshot:
Tool
π§ edit_file
{"find": "// Subscribe returns the events currently buffered for jobID (i.e. not\n// yet checkpointed) plus a channel of everything published from this\n// point on. The returned cancel func must be called when the caller is\n// done reading, to unregister and close the channel.\nfunc (h *Hub) Subscribe(jobID string) (buffered []Event, ch <-chan Event, cancel func()) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\tbuffered = append([]Event(nil), s.buf...)\n\n\tc := make(chan Event, subChanBuffer)", "path": "internal/livelog/hub.go", "replace": "// Subscribe returns the events currently buffered for jobID (i.e. not\n// yet checkpointed), the job's current sequence number (the Seq of the\n// most recently published event, 0 if none), and a channel of\n// everything published from this point on. The buffer snapshot and the\n// seq are taken under one lock, so the seq is always >= every buffered\n// event's Seq. The returned cancel func must be called when the caller\n// is done reading, to unregister and close the channel.\nfunc (h *Hub) Subscribe(jobID string) (buffered []Event, seq uint64, ch <-chan Event, cancel func()) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\tbuffered = append([]Event(nil), s.buf...)\n\tseq = s.seq\n\n\tc := make(chan Event, subChanBuffer)"}
Arguments
{"find": "// Subscribe returns the events currently buffered for jobID (i.e. not\n// yet checkpointed) plus a channel of everything published from this\n// point on. The returned cancel func must be called when the caller is\n// done reading, to unregister and close the channel.\nfunc (h *Hub) Subscribe(jobID string) (buffered []Event, ch <-chan Event, cancel func()) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\tbuffered = append([]Event(nil), s.buf...)\n\n\tc := make(chan Event, subChanBuffer)", "path": "internal/livelog/hub.go", "replace": "// Subscribe returns the events currently buffered for jobID (i.e. not\n// yet checkpointed), the job's current sequence number (the Seq of the\n// most recently published event, 0 if none), and a channel of\n// everything published from this point on. The buffer snapshot and the\n// seq are taken under one lock, so the seq is always >= every buffered\n// event's Seq. The returned cancel func must be called when the caller\n// is done reading, to unregister and close the channel.\nfunc (h *Hub) Subscribe(jobID string) (buffered []Event, seq uint64, ch <-chan Event, cancel func()) {\n\ts := h.get(jobID)\n\n\ts.mu.Lock()\n\tdefer s.mu.Unlock()\n\n\tbuffered = append([]Event(nil), s.buf...)\n\tseq = s.seq\n\n\tc := make(chan Event, subChanBuffer)"}
Result
1 occurrences replaced
Thinking
Next, I'll update web.go's handleJobEvents so that it sends a resync marker when the buffer is empty.
Now the SSE handler in web.go β send the `resync` marker when a subscription starts with an empty replay buffer:
Tool
π§ edit_file
{"find": "\tbuffered, ch, cancel := s.hub.Subscribe(id)\n\tdefer cancel()\n\n\twrite := func(ev livelog.Event) bool {\n\t\tdata, err := json.Marshal(ev)\n\t\tif err != nil {\n\t\t\treturn true\n\t\t}\n\n\t\tif _, err := fmt.Fprintf(w, \"data: %s\\n\\n\", data); err != nil {\n\t\t\treturn false\n\t\t}\n\n\t\tflusher.Flush()\n\n\t\treturn true\n\t}\n\n\tfor _, ev := range buffered {\n\t\tif !write(ev) {\n\t\t\treturn\n\t\t}\n\t}", "path": "internal/web/web.go", "replace": "\tbuffered, seq, ch, cancel := s.hub.Subscribe(id)\n\tdefer cancel()\n\n\twrite := func(ev livelog.Event) bool {\n\t\tdata, err := json.Marshal(ev)\n\t\tif err != nil {\n\t\t\treturn true\n\t\t}\n\n\t\tif _, err := fmt.Fprintf(w, \"data: %s\\n\\n\", data); err != nil {\n\t\t\treturn false\n\t\t}\n\n\t\tflusher.Flush()\n\n\t\treturn true\n\t}\n\n\t// If there is nothing to replay, tell the client where the hub is\n\t// at: if the hub is ahead of the client's last rendered event, the\n\t// client missed events that are no longer replayable and must fall\n\t// back to the static page. If there is something to replay, no\n\t// marker is needed β the replayed events' Seqs are the continuity\n\t// check (the client renders them if contiguous with what it has\n\t// and reloads otherwise).\n\tif len(buffered) == 0 {\n\t\tif !write(livelog.Event{Type: livelog.Resync, Seq: seq}) {\n\t\t\treturn\n\t\t}\n\t}\n\n\tfor _, ev := range buffered {\n\t\tif !write(ev) {\n\t\t\treturn\n\t\t}\n\t}"}
Arguments
{"find": "\tbuffered, ch, cancel := s.hub.Subscribe(id)\n\tdefer cancel()\n\n\twrite := func(ev livelog.Event) bool {\n\t\tdata, err := json.Marshal(ev)\n\t\tif err != nil {\n\t\t\treturn true\n\t\t}\n\n\t\tif _, err := fmt.Fprintf(w, \"data: %s\\n\\n\", data); err != nil {\n\t\t\treturn false\n\t\t}\n\n\t\tflusher.Flush()\n\n\t\treturn true\n\t}\n\n\tfor _, ev := range buffered {\n\t\tif !write(ev) {\n\t\t\treturn\n\t\t}\n\t}", "path": "internal/web/web.go", "replace": "\tbuffered, seq, ch, cancel := s.hub.Subscribe(id)\n\tdefer cancel()\n\n\twrite := func(ev livelog.Event) bool {\n\t\tdata, err := json.Marshal(ev)\n\t\tif err != nil {\n\t\t\treturn true\n\t\t}\n\n\t\tif _, err := fmt.Fprintf(w, \"data: %s\\n\\n\", data); err != nil {\n\t\t\treturn false\n\t\t}\n\n\t\tflusher.Flush()\n\n\t\treturn true\n\t}\n\n\t// If there is nothing to replay, tell the client where the hub is\n\t// at: if the hub is ahead of the client's last rendered event, the\n\t// client missed events that are no longer replayable and must fall\n\t// back to the static page. If there is something to replay, no\n\t// marker is needed β the replayed events' Seqs are the continuity\n\t// check (the client renders them if contiguous with what it has\n\t// and reloads otherwise).\n\tif len(buffered) == 0 {\n\t\tif !write(livelog.Event{Type: livelog.Resync, Seq: seq}) {\n\t\t\treturn\n\t\t}\n\t}\n\n\tfor _, ev := range buffered {\n\t\tif !write(ev) {\n\t\t\treturn\n\t\t}\n\t}"}
Result
1 occurrences replaced
Thinking
Next up is the JS in templates.go. Let's replace the script block. The current script block (from the earlier read):
```
{{if .Live}}
<script>
(function() {
var jobID = {{.Job.ID}};
var log = document.getElementById("log");
var reasoningBody = null;
var contentBody = null;
function nearBottom() {
return (window.innerHeight + window.scrollY) >= (document.body.offsetHeight - 80);
}
function newBlock(kind, label) {
...
}
function newToolBlock(ev) {
...
}
var es = new EventSource("/jobs/" + jobID + "/events");
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
var shouldScroll = nearBottom();
switch (ev.type) {
case "reasoning_start":
reasoningBody = newBlock("reasoning", "Thinking");
break;
case "reasoning_delta":
if (reasoningBody) reasoningBody.textContent += ev.text;
break;
case "reasoning_end":
// Model output routinely starts/ends with newlines; drop them
// so the finished block matches the static (trimmed) view.
if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();
reasoningBody = null;
break;
case "content_start":
contentBody = newBlock("content", null);
break;
case "content_delta":
if (contentBody) contentBody.textContent += ev.text;
break;
case "content_end":
if (contentBody) contentBody.textContent = contentBody.textContent.trim();
contentBody = null;
break;
case "tool":
newToolBlock(ev);
break;
case "status":
es.close();
location.reload();
return;
}
if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);
};
})();
</script>
{{end}}
```
I'll make the following targeted edits:
1. Replace the state variable declarations (reasoningBody/contentBody) with a blocks object + lastSeq.
2. Replace the onmessage handler.
3. Add the onDelta/onEnd/resyncPage helpers.
To make the edits accurately, I'll re-read the exact current text of the script section.
Now the client-side JS in templates.go. Let me re-read the exact current script text to make precise edits:
Tool
π§ read_file
{"end_line": 1004, "path": "internal/web/templates.go", "start_line": 879}
Arguments
{"end_line": 1004, "path": "internal/web/templates.go", "start_line": 879}
Result
{"path":"internal/web/templates.go","content":" {{if .Live}}\n \u003cscript\u003e\n (function() {\n var jobID = {{.Job.ID}};\n var log = document.getElementById(\"log\");\n var reasoningBody = null;\n var contentBody = null;\n\n function nearBottom() {\n return (window.innerHeight + window.scrollY) \u003e= (document.body.offsetHeight - 80);\n }\n\n function newBlock(kind, label) {\n var div = document.createElement(\"div\");\n div.className = \"block block-\" + kind;\n if (label) {\n var l = document.createElement(\"div\");\n l.className = \"block-label\";\n l.textContent = label;\n div.appendChild(l);\n }\n var body = document.createElement(\"div\");\n body.className = \"block-body\";\n div.appendChild(body);\n log.appendChild(div);\n return body;\n }\n\n function newToolBlock(ev) {\n var details = document.createElement(\"details\");\n details.className = \"block block-tool\" + (ev.error ? \" block-tool-error\" : \"\");\n\n var summary = document.createElement(\"summary\");\n\n var badge = document.createElement(\"span\");\n badge.className = \"tool-badge\";\n badge.textContent = \"Tool\";\n\n var text = document.createElement(\"span\");\n text.className = \"tool-summary-text\";\n\n var name = document.createElement(\"span\");\n name.className = \"tool-name\";\n name.textContent = \"π§ \" + ev.name;\n\n var preview = document.createElement(\"span\");\n preview.className = \"tool-args-preview\";\n preview.textContent = ev.arguments;\n\n text.appendChild(name);\n text.appendChild(preview);\n summary.appendChild(badge);\n summary.appendChild(text);\n details.appendChild(summary);\n\n var body = document.createElement(\"div\");\n body.className = \"block-body\";\n\n var argsLabel = document.createElement(\"div\");\n argsLabel.className = \"tool-section-label\";\n argsLabel.textContent = \"Arguments\";\n var argsPre = document.createElement(\"pre\");\n argsPre.textContent = ev.arguments;\n\n var resultLabel = document.createElement(\"div\");\n resultLabel.className = \"tool-section-label\";\n resultLabel.textContent = \"Result\";\n var resultPre = document.createElement(\"pre\");\n resultPre.textContent = ev.result;\n\n body.appendChild(argsLabel);\n body.appendChild(argsPre);\n body.appendChild(resultLabel);\n body.appendChild(resultPre);\n details.appendChild(body);\n log.appendChild(details);\n }\n\n var es = new EventSource(\"/jobs/\" + jobID + \"/events\");\n\n es.onmessage = function(e) {\n var ev = JSON.parse(e.data);\n var shouldScroll = nearBottom();\n\n switch (ev.type) {\n case \"reasoning_start\":\n reasoningBody = newBlock(\"reasoning\", \"Thinking\");\n break;\n case \"reasoning_delta\":\n if (reasoningBody) reasoningBody.textContent += ev.text;\n break;\n case \"reasoning_end\":\n // Model output routinely starts/ends with newlines; drop them\n // so the finished block matches the static (trimmed) view.\n if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();\n reasoningBody = null;\n break;\n case \"content_start\":\n contentBody = newBlock(\"content\", null);\n break;\n case \"content_delta\":\n if (contentBody) contentBody.textContent += ev.text;\n break;\n case \"content_end\":\n if (contentBody) contentBody.textContent = contentBody.textContent.trim();\n contentBody = null;\n break;\n case \"tool\":\n newToolBlock(ev);\n break;\n case \"status\":\n es.close();\n location.reload();\n return;\n }\n\n if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);\n };\n })();\n \u003c/script\u003e\n {{end}}\n\u003c/div\u003e\n\u003c/body\u003e\n\u003c/html\u003e\n{{end}}\n`","start_line":879,"end_line":1004,"total_lines":1004,"truncated":false}
Thinking
Now, I'll make edits to the JS. I'll do it in 3 edits:
1. State variables:
```js
var jobID = {{.Job.ID}};
var log = document.getElementById("log");
var reasoningBody = null;
var contentBody = null;
```
β
```js
var jobID = {{.Job.ID}};
var log = document.getElementById("log");
// Rendering state per block kind: the body of the open block (null
// if no block is open) and a buffer of deltas received before the
// block was created. Model output routinely starts with a newline,
// and a block that turns out to be whitespace-only must not be
// rendered at all (the static view also drops such blocks), so
// blocks are created lazily on the first non-whitespace text
// rather than on the *_start event β this is what prevents a
// whitespace-only turn from flashing an empty block shell
// (issue #60).
var blocks = {
reasoning: {body: null, buf: ""},
content: {body: null, buf: ""}
};
// lastSeq is the sequence number of the last event rendered. The
// server numbers every event per job, and when a subscription
// begins with nothing to replay, it sends a "resync" marker
// (with the hub's current number). Any break in the sequence β a
// gap from dropped events, or a replay of an event we've already
// rendered β means the block state above can no longer be
// trusted, so we fall back to the static page, which is always
// complete.
var lastSeq = 0;
```
2. After newToolBlock, add helpers (onDelta, onEnd, resyncPage) and move `var es` β actually `var es` is already after newToolBlock. I'll add the helpers between newToolBlock and `var es`.
3. Replace the onmessage handler.
Alright, let me write the edits.
Now I'll make the JS changes. First, the state variables:
Tool
π§ edit_file
{"find": " var jobID = {{.Job.ID}};\n var log = document.getElementById(\"log\");\n var reasoningBody = null;\n var contentBody = null;\n\n function nearBottom() {", "path": "internal/web/templates.go", "replace": " var jobID = {{.Job.ID}};\n var log = document.getElementById(\"log\");\n\n // Per-block-kind rendering state: the open block's body (null\n // while none is open) and a buffer of deltas received before the\n // block was created. Model output routinely starts with\n // newlines, and a block that ends up whitespace-only must not\n // render at all (the static view drops those blocks too), so a\n // block is created lazily on its first non-whitespace text\n // instead of on the *_start event β that's what keeps a\n // whitespace-only turn from flashing an empty block shell\n // (issue #60).\n var blocks = {\n reasoning: {body: null, buf: \"\"},\n content: {body: null, buf: \"\"}\n };\n\n // lastSeq is the sequence number of the last event rendered. The\n // server numbers every event per job and sends a \"resync\" marker\n // (with the hub's current number) when a subscription starts with\n // nothing to replay. Any break in the sequence β a gap from\n // dropped events, or a replay of an event we already rendered β\n // means the block state above can no longer be trusted, so we\n // fall back to the static page, which is always complete.\n var lastSeq = 0;\n\n function nearBottom() {"}
Arguments
{"find": " var jobID = {{.Job.ID}};\n var log = document.getElementById(\"log\");\n var reasoningBody = null;\n var contentBody = null;\n\n function nearBottom() {", "path": "internal/web/templates.go", "replace": " var jobID = {{.Job.ID}};\n var log = document.getElementById(\"log\");\n\n // Per-block-kind rendering state: the open block's body (null\n // while none is open) and a buffer of deltas received before the\n // block was created. Model output routinely starts with\n // newlines, and a block that ends up whitespace-only must not\n // render at all (the static view drops those blocks too), so a\n // block is created lazily on its first non-whitespace text\n // instead of on the *_start event β that's what keeps a\n // whitespace-only turn from flashing an empty block shell\n // (issue #60).\n var blocks = {\n reasoning: {body: null, buf: \"\"},\n content: {body: null, buf: \"\"}\n };\n\n // lastSeq is the sequence number of the last event rendered. The\n // server numbers every event per job and sends a \"resync\" marker\n // (with the hub's current number) when a subscription starts with\n // nothing to replay. Any break in the sequence β a gap from\n // dropped events, or a replay of an event we already rendered β\n // means the block state above can no longer be trusted, so we\n // fall back to the static page, which is always complete.\n var lastSeq = 0;\n\n function nearBottom() {"}
Result
1 occurrences replaced
Thinking
Next, I'll add the helper functions (resyncPage, onDelta, onEnd) between newToolBlock and `var es`:
Tool
π§ edit_file
{"find": " body.appendChild(argsLabel);\n body.appendChild(argsPre);\n body.appendChild(resultLabel);\n body.appendChild(resultPre);\n details.appendChild(body);\n log.appendChild(details);\n }\n\n var es = new EventSource(\"/jobs/\" + jobID + \"/events\");\n\n es.onmessage = function(e) {\n var ev = JSON.parse(e.data);\n var shouldScroll = nearBottom();\n\n switch (ev.type) {\n case \"reasoning_start\":\n reasoningBody = newBlock(\"reasoning\", \"Thinking\");\n break;\n case \"reasoning_delta\":\n if (reasoningBody) reasoningBody.textContent += ev.text;\n break;\n case \"reasoning_end\":\n // Model output routinely starts/ends with newlines; drop them\n // so the finished block matches the static (trimmed) view.\n if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();\n reasoningBody = null;\n break;\n case \"content_start\":\n contentBody = newBlock(\"content\", null);\n break;\n case \"content_delta\":\n if (contentBody) contentBody.textContent += ev.text;\n break;\n case \"content_end\":\n if (contentBody) contentBody.textContent = contentBody.textContent.trim();\n contentBody = null;\n break;\n case \"tool\":\n newToolBlock(ev);\n break;\n case \"status\":\n es.close();\n location.reload();\n return;\n }\n\n if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);\n };\n })();", "path": "internal/web/templates.go", "replace": " body.appendChild(argsLabel);\n body.appendChild(argsPre);\n body.appendChild(resultLabel);\n body.appendChild(resultPre);\n details.appendChild(body);\n log.appendChild(details);\n }\n\n function resyncPage() {\n es.close();\n location.reload();\n }\n\n function onDelta(kind, delta) {\n var b = blocks[kind];\n if (b.body) {\n b.body.textContent += delta;\n return;\n }\n b.buf += delta;\n if (b.buf.trim() === \"\") return; // whitespace so far: no block yet\n b.body = newBlock(kind, kind === \"reasoning\" ? \"Thinking\" : null);\n b.body.textContent = b.buf;\n b.buf = \"\";\n }\n\n function onEnd(kind) {\n var b = blocks[kind];\n if (b.body) {\n // Model output routinely starts/ends with newlines; drop them\n // so the finished block matches the static (trimmed) view,\n // and drop the block entirely if nothing is left.\n b.body.textContent = b.body.textContent.trim();\n if (b.body.textContent === \"\") b.body.parentElement.remove();\n b.body = null;\n }\n b.buf = \"\";\n }\n\n var es = new EventSource(\"/jobs/\" + jobID + \"/events\");\n\n es.onmessage = function(e) {\n var ev = JSON.parse(e.data);\n\n if (ev.type === \"resync\") {\n // The subscription started with nothing to replay, and the\n // hub is at seq ev.seq. If we last rendered something else,\n // we missed events that are no longer replayable.\n if (lastSeq !== 0 && (typeof ev.seq !== \"number\" || ev.seq !== lastSeq)) {\n resyncPage();\n }\n return;\n }\n\n if (typeof ev.seq === \"number\") {\n if (lastSeq === 0) {\n lastSeq = ev.seq; // first event: fresh page, or joining a replay\n } else if (ev.seq === lastSeq + 1) {\n lastSeq = ev.seq; // contiguous: render\n } else {\n resyncPage(); // gap (dropped events) or duplicate replay\n return;\n }\n }\n\n var shouldScroll = nearBottom();\n\n switch (ev.type) {\n case \"reasoning_start\":\n blocks.reasoning.body = null;\n blocks.reasoning.buf = \"\";\n break;\n case \"reasoning_delta\":\n onDelta(\"reasoning\", ev.text);\n break;\n case \"reasoning_end\":\n onEnd(\"reasoning\");\n break;\n case \"content_start\":\n blocks.content.body = null;\n blocks.content.buf = \"\";\n break;\n case \"content_delta\":\n onDelta(\"content\", ev.text);\n break;\n case \"content_end\":\n onEnd(\"content\");\n break;\n case \"tool\":\n newToolBlock(ev);\n break;\n case \"status\":\n resyncPage();\n return;\n }\n\n if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);\n };\n })();"}
Arguments
{"find": " body.appendChild(argsLabel);\n body.appendChild(argsPre);\n body.appendChild(resultLabel);\n body.appendChild(resultPre);\n details.appendChild(body);\n log.appendChild(details);\n }\n\n var es = new EventSource(\"/jobs/\" + jobID + \"/events\");\n\n es.onmessage = function(e) {\n var ev = JSON.parse(e.data);\n var shouldScroll = nearBottom();\n\n switch (ev.type) {\n case \"reasoning_start\":\n reasoningBody = newBlock(\"reasoning\", \"Thinking\");\n break;\n case \"reasoning_delta\":\n if (reasoningBody) reasoningBody.textContent += ev.text;\n break;\n case \"reasoning_end\":\n // Model output routinely starts/ends with newlines; drop them\n // so the finished block matches the static (trimmed) view.\n if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();\n reasoningBody = null;\n break;\n case \"content_start\":\n contentBody = newBlock(\"content\", null);\n break;\n case \"content_delta\":\n if (contentBody) contentBody.textContent += ev.text;\n break;\n case \"content_end\":\n if (contentBody) contentBody.textContent = contentBody.textContent.trim();\n contentBody = null;\n break;\n case \"tool\":\n newToolBlock(ev);\n break;\n case \"status\":\n es.close();\n location.reload();\n return;\n }\n\n if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);\n };\n })();", "path": "internal/web/templates.go", "replace": " body.appendChild(argsLabel);\n body.appendChild(argsPre);\n body.appendChild(resultLabel);\n body.appendChild(resultPre);\n details.appendChild(body);\n log.appendChild(details);\n }\n\n function resyncPage() {\n es.close();\n location.reload();\n }\n\n function onDelta(kind, delta) {\n var b = blocks[kind];\n if (b.body) {\n b.body.textContent += delta;\n return;\n }\n b.buf += delta;\n if (b.buf.trim() === \"\") return; // whitespace so far: no block yet\n b.body = newBlock(kind, kind === \"reasoning\" ? \"Thinking\" : null);\n b.body.textContent = b.buf;\n b.buf = \"\";\n }\n\n function onEnd(kind) {\n var b = blocks[kind];\n if (b.body) {\n // Model output routinely starts/ends with newlines; drop them\n // so the finished block matches the static (trimmed) view,\n // and drop the block entirely if nothing is left.\n b.body.textContent = b.body.textContent.trim();\n if (b.body.textContent === \"\") b.body.parentElement.remove();\n b.body = null;\n }\n b.buf = \"\";\n }\n\n var es = new EventSource(\"/jobs/\" + jobID + \"/events\");\n\n es.onmessage = function(e) {\n var ev = JSON.parse(e.data);\n\n if (ev.type === \"resync\") {\n // The subscription started with nothing to replay, and the\n // hub is at seq ev.seq. If we last rendered something else,\n // we missed events that are no longer replayable.\n if (lastSeq !== 0 && (typeof ev.seq !== \"number\" || ev.seq !== lastSeq)) {\n resyncPage();\n }\n return;\n }\n\n if (typeof ev.seq === \"number\") {\n if (lastSeq === 0) {\n lastSeq = ev.seq; // first event: fresh page, or joining a replay\n } else if (ev.seq === lastSeq + 1) {\n lastSeq = ev.seq; // contiguous: render\n } else {\n resyncPage(); // gap (dropped events) or duplicate replay\n return;\n }\n }\n\n var shouldScroll = nearBottom();\n\n switch (ev.type) {\n case \"reasoning_start\":\n blocks.reasoning.body = null;\n blocks.reasoning.buf = \"\";\n break;\n case \"reasoning_delta\":\n onDelta(\"reasoning\", ev.text);\n break;\n case \"reasoning_end\":\n onEnd(\"reasoning\");\n break;\n case \"content_start\":\n blocks.content.body = null;\n blocks.content.buf = \"\";\n break;\n case \"content_delta\":\n onDelta(\"content\", ev.text);\n break;\n case \"content_end\":\n onEnd(\"content\");\n break;\n case \"tool\":\n newToolBlock(ev);\n break;\n case \"status\":\n resyncPage();\n return;\n }\n\n if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);\n };\n })();"}
Result
1 occurrences replaced
Thinking
Wait β there's a JS scoping issue: `resyncPage` references `es`, but `es` is declared with `var es = new EventSource(...)` after the function definition. Function declarations are hoisted, and `es` is only referenced when `resyncPage` is called (which happens inside onmessage, i.e., after `es` has been assigned). So it's fine.
But wait, there's another subtle issue: `resyncPage` is a function declaration that references `es` β and `var es` is in the same function scope. When `resyncPage()` is called from within `es.onmessage`, `es` is already initialized. β
Next, update the hub tests to match the new Subscribe signature, and add seq tests.
Now update the hub tests for the new `Subscribe` signature and add sequence-number tests:
Tool
π§ edit_file
{"find": "\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\tbuffered, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif len(buffered) != 2 {\n\t\tt.Fatalf(\"expected 2 buffered events, got %d\", len(buffered))\n\t}\n\tif buffered[1].Text != \"hi\" {\n\t\tt.Fatalf(\"unexpected buffered event: %+v\", buffered[1])\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \" there\"})\n\n\tev := recv(t, ch)\n\tif ev.Text != \" there\" {\n\t\tt.Fatalf(\"expected live delta %q, got %+v\", \" there\", ev)\n\t}\n}", "path": "internal/livelog/hub_test.go", "replace": "\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\tbuffered, seq, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif len(buffered) != 2 {\n\t\tt.Fatalf(\"expected 2 buffered events, got %d\", len(buffered))\n\t}\n\tif buffered[1].Text != \"hi\" {\n\t\tt.Fatalf(\"unexpected buffered event: %+v\", buffered[1])\n\t}\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected current seq 2, got %d\", seq)\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \" there\"})\n\n\tev := recv(t, ch)\n\tif ev.Text != \" there\" {\n\t\tt.Fatalf(\"expected live delta %q, got %+v\", \" there\", ev)\n\t}\n\tif ev.Seq != 3 {\n\t\tt.Fatalf(\"expected live delta to carry seq 3, got %+v\", ev)\n\t}\n}\n\n// TestPublishAssignsMonotonicSeqs verifies that every published event\n// gets the job's next sequence number, and that seqs are per-job: a\n// client uses them to detect dropped events (gaps) and fall back to\n// the static page (issue #60).\nfunc TestPublishAssignsMonotonicSeqs(t *testing.T) {\n\th := NewHub()\n\n\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Publish(\"job-2\", Event{Type: ContentStart})\n\n\tbuffered, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected job-1's current seq to be 2, got %d\", seq)\n\t}\n\tfor i, ev := range buffered {\n\t\tif ev.Seq != uint64(i+1) {\n\t\t\tt.Fatalf(\"expected buffered event %d to have seq %d, got %+v\", i, i+1, ev)\n\t\t}\n\t}\n\n\t// job-2 has its own seq space, independent of job-1's.\n\tbuffered2, seq2, cancel2 := h.Subscribe(\"job-2\")\n\tdefer cancel2()\n\n\tif seq2 != 1 || len(buffered2) != 1 || buffered2[0].Seq != 1 {\n\t\tt.Fatalf(\"expected job-2 to have its own seq space, got seq=%d buffered=%+v\", seq2, buffered2)\n\t}\n}\n\n// TestSubscribeSeqTracksLatestPublished verifies that the seq returned\n// by Subscribe is 0 for a fresh job and follows publishes, so the web\n// layer can send a resync marker that lets a reconnecting client tell\n// whether it missed events.\nfunc TestSubscribeSeqTracksLatestPublished(t *testing.T) {\n\th := NewHub()\n\n\t_, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 0 {\n\t\tt.Fatalf(\"expected seq 0 for a fresh job, got %d\", seq)\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\t_, seq, _ = h.Subscribe(\"job-1\")\n\tif seq != 1 {\n\t\tt.Fatalf(\"expected seq 1 after one publish, got %d\", seq)\n\t}\n}"}
Arguments
{"find": "\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\tbuffered, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif len(buffered) != 2 {\n\t\tt.Fatalf(\"expected 2 buffered events, got %d\", len(buffered))\n\t}\n\tif buffered[1].Text != \"hi\" {\n\t\tt.Fatalf(\"unexpected buffered event: %+v\", buffered[1])\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \" there\"})\n\n\tev := recv(t, ch)\n\tif ev.Text != \" there\" {\n\t\tt.Fatalf(\"expected live delta %q, got %+v\", \" there\", ev)\n\t}\n}", "path": "internal/livelog/hub_test.go", "replace": "\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\tbuffered, seq, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif len(buffered) != 2 {\n\t\tt.Fatalf(\"expected 2 buffered events, got %d\", len(buffered))\n\t}\n\tif buffered[1].Text != \"hi\" {\n\t\tt.Fatalf(\"unexpected buffered event: %+v\", buffered[1])\n\t}\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected current seq 2, got %d\", seq)\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \" there\"})\n\n\tev := recv(t, ch)\n\tif ev.Text != \" there\" {\n\t\tt.Fatalf(\"expected live delta %q, got %+v\", \" there\", ev)\n\t}\n\tif ev.Seq != 3 {\n\t\tt.Fatalf(\"expected live delta to carry seq 3, got %+v\", ev)\n\t}\n}\n\n// TestPublishAssignsMonotonicSeqs verifies that every published event\n// gets the job's next sequence number, and that seqs are per-job: a\n// client uses them to detect dropped events (gaps) and fall back to\n// the static page (issue #60).\nfunc TestPublishAssignsMonotonicSeqs(t *testing.T) {\n\th := NewHub()\n\n\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Publish(\"job-2\", Event{Type: ContentStart})\n\n\tbuffered, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected job-1's current seq to be 2, got %d\", seq)\n\t}\n\tfor i, ev := range buffered {\n\t\tif ev.Seq != uint64(i+1) {\n\t\t\tt.Fatalf(\"expected buffered event %d to have seq %d, got %+v\", i, i+1, ev)\n\t\t}\n\t}\n\n\t// job-2 has its own seq space, independent of job-1's.\n\tbuffered2, seq2, cancel2 := h.Subscribe(\"job-2\")\n\tdefer cancel2()\n\n\tif seq2 != 1 || len(buffered2) != 1 || buffered2[0].Seq != 1 {\n\t\tt.Fatalf(\"expected job-2 to have its own seq space, got seq=%d buffered=%+v\", seq2, buffered2)\n\t}\n}\n\n// TestSubscribeSeqTracksLatestPublished verifies that the seq returned\n// by Subscribe is 0 for a fresh job and follows publishes, so the web\n// layer can send a resync marker that lets a reconnecting client tell\n// whether it missed events.\nfunc TestSubscribeSeqTracksLatestPublished(t *testing.T) {\n\th := NewHub()\n\n\t_, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 0 {\n\t\tt.Fatalf(\"expected seq 0 for a fresh job, got %d\", seq)\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\t_, seq, _ = h.Subscribe(\"job-1\")\n\tif seq != 1 {\n\t\tt.Fatalf(\"expected seq 1 after one publish, got %d\", seq)\n\t}\n}"}
Result
1 occurrences replaced
Thinking
Next, I'll update the remaining Subscribe calls within hub_test.go:
- Line 56: `buffered, _, cancel := h.Subscribe("job-1")` β `buffered, _, _, cancel := ...`
- Line 67: `_, ch, cancel := h.Subscribe("job-1")` β `_, _, ch, cancel := ...`
- Line 93: `buffered, ch, cancel := h.Subscribe("job-1")` β `buffered, _, ch, cancel := ...`
- Line 110: `_, ch, cancel := h.Subscribe("job-1")` β `_, _, ch, cancel := ...`
Tool
π§ edit_file
{"find": "\th.Checkpoint(\"job-1\")\n\n\tbuffered, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()", "path": "internal/livelog/hub_test.go", "replace": "\th.Checkpoint(\"job-1\")\n\n\tbuffered, _, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()"}
Arguments
{"find": "\th.Checkpoint(\"job-1\")\n\n\tbuffered, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()", "path": "internal/livelog/hub_test.go", "replace": "\th.Checkpoint(\"job-1\")\n\n\tbuffered, _, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()"}
Result
1 occurrences replaced
Tool
π§ edit_file
{"find": "func TestCloseTerminatesSubscribers(t *testing.T) {\n\th := NewHub()\n\n\t_, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()", "path": "internal/livelog/hub_test.go", "replace": "func TestCloseTerminatesSubscribers(t *testing.T) {\n\th := NewHub()\n\n\t_, _, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()"}
Arguments
{"find": "func TestCloseTerminatesSubscribers(t *testing.T) {\n\th := NewHub()\n\n\t_, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()", "path": "internal/livelog/hub_test.go", "replace": "func TestCloseTerminatesSubscribers(t *testing.T) {\n\th := NewHub()\n\n\t_, _, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()"}
Result
1 occurrences replaced
Tool
π§ edit_file
{"find": "\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Close(\"job-1\")\n\n\tbuffered, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()", "path": "internal/livelog/hub_test.go", "replace": "\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Close(\"job-1\")\n\n\tbuffered, _, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()"}
Arguments
{"find": "\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Close(\"job-1\")\n\n\tbuffered, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()", "path": "internal/livelog/hub_test.go", "replace": "\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Close(\"job-1\")\n\n\tbuffered, _, ch, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()"}
Result
1 occurrences replaced
Tool
π§ edit_file
{"find": "func TestCancelUnregistersSubscriber(t *testing.T) {\n\th := NewHub()\n\n\t_, ch, cancel := h.Subscribe(\"job-1\")\n\tcancel()", "path": "internal/livelog/hub_test.go", "replace": "func TestCancelUnregistersSubscriber(t *testing.T) {\n\th := NewHub()\n\n\t_, _, ch, cancel := h.Subscribe(\"job-1\")\n\tcancel()"}
Arguments
{"find": "func TestCancelUnregistersSubscriber(t *testing.T) {\n\th := NewHub()\n\n\t_, ch, cancel := h.Subscribe(\"job-1\")\n\tcancel()", "path": "internal/livelog/hub_test.go", "replace": "func TestCancelUnregistersSubscriber(t *testing.T) {\n\th := NewHub()\n\n\t_, _, ch, cancel := h.Subscribe(\"job-1\")\n\tcancel()"}
Result
1 occurrences replaced
Thinking
Next, let's add web tests for the SSE sequence/resync behavior. I'll add them after TestJobsAndDetail in web_test.go. Let's add a new test:
```go
// TestJobEventsSequenceNumbers verifies that the SSE stream numbers
// every event (per job, monotonically increasing) and, when there's
// nothing to replay, starts with a resync marker carrying the hub's
// current seq. This allows clients to detect dropped events and fall
// back to the static page (issue #60).
func TestJobEventsSequenceNumbers(t *testing.T) {
s, st := testServer(t)
ctx := context.Background()
if err := st.CreateJob(ctx, store.Job{ID: "job-1", EventKind: "issue:new", Agent: "leon", Owner: "acme", Repo: "widgets", IssueIndex: 1}); err != nil {
t.Fatal(err)
}
// Nothing buffered: the stream must start with a resync marker
// carrying the hub's current seq (0 for a new job).
evCtx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
defer cancel()
rr := httptest.NewRecorder()
s.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/jobs/job-1/events", nil).WithContext(evCtx))
if rr.Code != http.StatusOK {
t.Fatalf("expected 200, got %d: %s", rr.Code, rr.Body.String())
}
if !strings.HasPrefix(rr.Body.String(), `data: {"type":"resync"}`) {
t.Fatalf("expected the stream to start with a resync marker, got: %s", rr.Body.String())
}
// After publishing a block, a new subscriber receives the buffered
// events numbered contiguously starting from 1, with no resync
// marker (the replayed seqs are the continuity check).
s.hub.Publish("job-1", livelog.Event{Type: livelog.ContentStart})
s.hub.Publish("job-1", livelog.Event{Type: livelog.ContentDelta, Text: "hi"})
evCtx2, cancel2 := context.WithTimeout(context.Background(), 100*time.Millisecond)
defer cancel2()
rr = httptest.NewRecorder()
s.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/jobs/job-1/events", nil).WithContext(evCtx2))
body := rr.Body.String()
if !strings.Contains(body, `{"type":"content_start","seq":1}`) || !strings.Contains(body, `{"type":"content_delta","seq":2,"text":"hi"}`) {
t.Fatalf("expected buffered events numbered 1 and 2, got: %s", body)
}
if strings.Contains(body, "resync") {
t.Fatalf("did not expect a resync marker with a non-empty buffer, got: %s", body)
}
}
```
Wait β there's one issue: the first request uses a 100ms timeout. The handler writes the resync, then blocks on the select (channel/heartbeat/context). After 100ms the context is canceled β the handler returns. Body = `data: {"type":"resync"}\n\n`. β
Second request: the buffer has 2 events β no resync, writes both, then blocks. Body = `data: {"type":"content_start","seq":1}\n\ndata: {"type":"content_delta","seq":2,"text":"hi"}\n\n`. β
JSON marshaling of Event{Type: ContentStart, Seq: 1}: the field order is Type, Seq, Text, Name, Arguments, Result, Error, Status β `{"type":"content_start","seq":1}`. β (Text is omitted since it's empty, and the rest are omitted too.)
Event{Type: ContentDelta, Seq: 2, Text: "hi"} β `{"type":"content_delta","seq":2,"text":"hi"}`. β
Also, I should double-check that the existing test TestJobsAndDetail still passes β it checks `strings.Contains(rr.Body.String(), "streaming")` β the delta event is now `{"type":"content_delta","seq":1,"text":"streaming"}` β it still contains "streaming". β And the resync marker is written first: `data: {"type":"resync"}\n\ndata: {...streaming...}\n\n`. β No problem.
Alright, let's add the test.
Now add a web test for the SSE sequence/resync contract:
Tool
π§ edit_file
{"find": "// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved.", "path": "internal/web/web_test.go", "replace": "// TestJobEventsSequenceNumbers verifies that the SSE stream numbers\n// every event (per job, monotonically) and opens with a resync marker\n// carrying the hub's current seq when there is nothing to replay, so a\n// client can detect dropped events and fall back to the static page\n// (issue #60).\nfunc TestJobEventsSequenceNumbers(t *testing.T) {\n\ts, st := testServer(t)\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\t// Nothing buffered: the stream must open with a resync marker\n\t// carrying the hub's current seq (0 for a fresh job, so omitted).\n\tevCtx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)\n\tdefer cancel()\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1/events\", nil).WithContext(evCtx))\n\tif rr.Code != http.StatusOK {\n\t\tt.Fatalf(\"expected 200, got %d: %s\", rr.Code, rr.Body.String())\n\t}\n\tif !strings.HasPrefix(rr.Body.String(), `data: {\"type\":\"resync\"}`) {\n\t\tt.Fatalf(\"expected stream to open with a resync marker, got: %s\", rr.Body.String())\n\t}\n\n\t// After a block is published, a new subscriber gets the buffered\n\t// events numbered contiguously from 1, with no resync marker: the\n\t// replayed seqs are the continuity check.\n\ts.hub.Publish(\"job-1\", livelog.Event{Type: livelog.ContentStart})\n\ts.hub.Publish(\"job-1\", livelog.Event{Type: livelog.ContentDelta, Text: \"hi\"})\n\n\tevCtx2, cancel2 := context.WithTimeout(context.Background(), 100*time.Millisecond)\n\tdefer cancel2()\n\n\trr = httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1/events\", nil).WithContext(evCtx2))\n\tbody := rr.Body.String()\n\n\tif !strings.Contains(body, `{\"type\":\"content_start\",\"seq\":1}`) ||\n\t\t!strings.Contains(body, `{\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}`) {\n\t\tt.Fatalf(\"expected buffered events numbered 1 and 2, got: %s\", body)\n\t}\n\tif strings.Contains(body, \"resync\") {\n\t\tt.Fatalf(\"did not expect a resync marker with a non-empty buffer, got: %s\", body)\n\t}\n}\n\n// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved."}
Arguments
{"find": "// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved.", "path": "internal/web/web_test.go", "replace": "// TestJobEventsSequenceNumbers verifies that the SSE stream numbers\n// every event (per job, monotonically) and opens with a resync marker\n// carrying the hub's current seq when there is nothing to replay, so a\n// client can detect dropped events and fall back to the static page\n// (issue #60).\nfunc TestJobEventsSequenceNumbers(t *testing.T) {\n\ts, st := testServer(t)\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\t// Nothing buffered: the stream must open with a resync marker\n\t// carrying the hub's current seq (0 for a fresh job, so omitted).\n\tevCtx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)\n\tdefer cancel()\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1/events\", nil).WithContext(evCtx))\n\tif rr.Code != http.StatusOK {\n\t\tt.Fatalf(\"expected 200, got %d: %s\", rr.Code, rr.Body.String())\n\t}\n\tif !strings.HasPrefix(rr.Body.String(), `data: {\"type\":\"resync\"}`) {\n\t\tt.Fatalf(\"expected stream to open with a resync marker, got: %s\", rr.Body.String())\n\t}\n\n\t// After a block is published, a new subscriber gets the buffered\n\t// events numbered contiguously from 1, with no resync marker: the\n\t// replayed seqs are the continuity check.\n\ts.hub.Publish(\"job-1\", livelog.Event{Type: livelog.ContentStart})\n\ts.hub.Publish(\"job-1\", livelog.Event{Type: livelog.ContentDelta, Text: \"hi\"})\n\n\tevCtx2, cancel2 := context.WithTimeout(context.Background(), 100*time.Millisecond)\n\tdefer cancel2()\n\n\trr = httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1/events\", nil).WithContext(evCtx2))\n\tbody := rr.Body.String()\n\n\tif !strings.Contains(body, `{\"type\":\"content_start\",\"seq\":1}`) ||\n\t\t!strings.Contains(body, `{\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}`) {\n\t\tt.Fatalf(\"expected buffered events numbered 1 and 2, got: %s\", body)\n\t}\n\tif strings.Contains(body, \"resync\") {\n\t\tt.Fatalf(\"did not expect a resync marker with a non-empty buffer, got: %s\", body)\n\t}\n}\n\n// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved."}
Result
1 occurrences replaced
Thinking
Next, let's build and run the tests. Also, I should verify that the JS is syntactically valid. If node is available in the container, I can extract the JS and check it with node. Let's start with the Go build first.
Now let's build and run the tests:
Tool
π§ bash
{"command": "cd /project && go build ./... && go vet ./internal/livelog/ ./internal/web/ && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -10"}
Arguments
{"command": "cd /project && go build ./... && go vet ./internal/livelog/ ./internal/web/ && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -10"}
Result
ERROR CALLING TOOL: command exited with status 1: # github.com/abrander/zoo/internal/livelog
internal/livelog/hub.go:162:22: not enough return values
have ([]Event, chan Event, func())
want ([]Event, uint64, <-chan Event, func())
Thinking
The return statement of the Subscribe function still has the old signature. Let's check the end of Subscribe.
The `Subscribe` return statement still needs updating:
Tool
π§ read_file
{"end_line": 175, "path": "internal/livelog/hub.go", "start_line": 140}
Arguments
{"end_line": 175, "path": "internal/livelog/hub.go", "start_line": 140}
Result
{"path":"internal/livelog/hub.go","content":"\tdefer s.mu.Unlock()\n\n\tbuffered = append([]Event(nil), s.buf...)\n\tseq = s.seq\n\n\tc := make(chan Event, subChanBuffer)\n\ts.subs[c] = struct{}{}\n\n\tvar once sync.Once\n\n\tcancelFn := func() {\n\t\tonce.Do(func() {\n\t\t\ts.mu.Lock()\n\t\t\tdefer s.mu.Unlock()\n\n\t\t\tif _, ok := s.subs[c]; ok {\n\t\t\t\tdelete(s.subs, c)\n\t\t\t\tclose(c)\n\t\t\t}\n\t\t})\n\t}\n\n\treturn buffered, c, cancelFn\n}\n\n// Close publishes a terminal Status event, disconnects every current\n// subscriber, and drops jobID's state. Call this exactly once, when the\n// job's run has finished.\nfunc (h *Hub) Close(jobID string) {\n\th.Publish(jobID, Event{Type: Status, Status: \"done\"})\n\n\th.mu.Lock()\n\ts, ok := h.jobs[jobID]\n\tdelete(h.jobs, jobID)\n\th.mu.Unlock()\n","start_line":140,"end_line":175,"total_lines":188,"truncated":true}
Thinking
The return statement needs to be `return buffered, seq, c, cancelFn`.
Tool
π§ edit_file
{"find": "\treturn buffered, c, cancelFn\n}", "path": "internal/livelog/hub.go", "replace": "\treturn buffered, seq, c, cancelFn\n}"}
Arguments
{"find": "\treturn buffered, c, cancelFn\n}", "path": "internal/livelog/hub.go", "replace": "\treturn buffered, seq, c, cancelFn\n}"}
Result
1 occurrences replaced
Thinking
The build failed because the return statement of the Subscribe function was still using the old signature. Let's try rebuilding.
Tool
π§ bash
{"command": "cd /project && go build ./... && go vet ./internal/livelog/ ./internal/web/ && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -10"}
Arguments
{"command": "cd /project && go build ./... && go vet ./internal/livelog/ ./internal/web/ && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -10"}
Result
ERROR CALLING TOOL: command exited with status 1: # github.com/abrander/zoo/internal/livelog
# [github.com/abrander/zoo/internal/livelog]
vet: internal/livelog/hub_test.go:66:27: assignment mismatch: 3 variables but h.Subscribe returns 4 values
Thinking
There's still a Subscribe call remaining in hub_test.go that I missed. Line 66. Let me check β it's probably inside TestCheckpointClearsBuffer... no wait, I should have fixed that one. Let me take a look at line 66.
Tool
π§ read_file
{"end_line": 75, "path": "internal/livelog/hub_test.go", "start_line": 55}
Arguments
{"end_line": 75, "path": "internal/livelog/hub_test.go", "start_line": 55}
Result
{"path":"internal/livelog/hub_test.go","content":"// TestPublishAssignsMonotonicSeqs verifies that every published event\n// gets the job's next sequence number, and that seqs are per-job: a\n// client uses them to detect dropped events (gaps) and fall back to\n// the static page (issue #60).\nfunc TestPublishAssignsMonotonicSeqs(t *testing.T) {\n\th := NewHub()\n\n\th.Publish(\"job-1\", Event{Type: ContentStart})\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\th.Publish(\"job-2\", Event{Type: ContentStart})\n\n\tbuffered, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected job-1's current seq to be 2, got %d\", seq)\n\t}\n\tfor i, ev := range buffered {\n\t\tif ev.Seq != uint64(i+1) {\n\t\t\tt.Fatalf(\"expected buffered event %d to have seq %d, got %+v\", i, i+1, ev)\n\t\t}","start_line":55,"end_line":75,"total_lines":184,"truncated":true}
Thinking
The new test I added uses `buffered, seq, cancel := h.Subscribe("job-1")` β 3 variables, but Subscribe currently returns 4 values. I need to fix both of the new test calls:
1. `buffered, seq, cancel := h.Subscribe("job-1")` β `buffered, seq, _, cancel := h.Subscribe("job-1")`
2. `buffered2, seq2, cancel2 := h.Subscribe("job-2")` β `buffered2, seq2, _, cancel2 := h.Subscribe("job-2")`
3. `_, seq, cancel := h.Subscribe("job-1")` β `_, seq, _, cancel := h.Subscribe("job-1")`
4. `_, seq, _ = h.Subscribe("job-1")` β `_, seq, _, _ = h.Subscribe("job-1")`
My new tests have the old 3-value signature. Fixing:
Tool
π§ edit_file
{"find": "\tbuffered, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected job-1's current seq to be 2, got %d\", seq)\n\t}", "path": "internal/livelog/hub_test.go", "replace": "\tbuffered, seq, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected job-1's current seq to be 2, got %d\", seq)\n\t}"}
Arguments
{"find": "\tbuffered, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected job-1's current seq to be 2, got %d\", seq)\n\t}", "path": "internal/livelog/hub_test.go", "replace": "\tbuffered, seq, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 2 {\n\t\tt.Fatalf(\"expected job-1's current seq to be 2, got %d\", seq)\n\t}"}
Result
1 occurrences replaced
Tool
π§ edit_file
{"find": "\tbuffered2, seq2, cancel2 := h.Subscribe(\"job-2\")\n\tdefer cancel2()", "path": "internal/livelog/hub_test.go", "replace": "\tbuffered2, seq2, _, cancel2 := h.Subscribe(\"job-2\")\n\tdefer cancel2()"}
Arguments
{"find": "\tbuffered2, seq2, cancel2 := h.Subscribe(\"job-2\")\n\tdefer cancel2()", "path": "internal/livelog/hub_test.go", "replace": "\tbuffered2, seq2, _, cancel2 := h.Subscribe(\"job-2\")\n\tdefer cancel2()"}
Result
1 occurrences replaced
Tool
π§ edit_file
{"find": "\t_, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 0 {\n\t\tt.Fatalf(\"expected seq 0 for a fresh job, got %d\", seq)\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\t_, seq, _ = h.Subscribe(\"job-1\")\n\tif seq != 1 {\n\t\tt.Fatalf(\"expected seq 1 after one publish, got %d\", seq)\n\t}", "path": "internal/livelog/hub_test.go", "replace": "\t_, seq, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 0 {\n\t\tt.Fatalf(\"expected seq 0 for a fresh job, got %d\", seq)\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\t_, seq, _, _ = h.Subscribe(\"job-1\")\n\tif seq != 1 {\n\t\tt.Fatalf(\"expected seq 1 after one publish, got %d\", seq)\n\t}"}
Arguments
{"find": "\t_, seq, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 0 {\n\t\tt.Fatalf(\"expected seq 0 for a fresh job, got %d\", seq)\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\t_, seq, _ = h.Subscribe(\"job-1\")\n\tif seq != 1 {\n\t\tt.Fatalf(\"expected seq 1 after one publish, got %d\", seq)\n\t}", "path": "internal/livelog/hub_test.go", "replace": "\t_, seq, _, cancel := h.Subscribe(\"job-1\")\n\tdefer cancel()\n\n\tif seq != 0 {\n\t\tt.Fatalf(\"expected seq 0 for a fresh job, got %d\", seq)\n\t}\n\n\th.Publish(\"job-1\", Event{Type: ContentDelta, Text: \"hi\"})\n\n\t_, seq, _, _ = h.Subscribe(\"job-1\")\n\tif seq != 1 {\n\t\tt.Fatalf(\"expected seq 1 after one publish, got %d\", seq)\n\t}"}
Result
1 occurrences replaced
Thinking
Wait, in TestSubscribeSeqTracksLatestPublished, the second Subscribe call `_, seq, _, _ = h.Subscribe("job-1")` β this is an assignment (not a declaration), so it's fine. But the first one: `_, seq, _, cancel := h.Subscribe("job-1")` β this declares seq and cancel. OK.
Alright, let's build and test again.
Tool
π§ bash
{"command": "cd /project && go build ./... && go vet ./internal/livelog/ ./internal/web/ && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -10"}
Arguments
{"command": "cd /project && go build ./... && go vet ./internal/livelog/ ./internal/web/ && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -10"}
Result
ok github.com/abrander/zoo/internal/livelog 0.052s
ok github.com/abrander/zoo/internal/web 1.362s
Thinking
All tests pass. Next, I'll verify whether the JS syntax is valid. If node is available in the container, I can extract the script from the template and run `node --check` on it. The template contains Go template actions like `{{.Job.ID}}`, which need to be replaced with valid JS values before the syntax check.
I'll write a small Go program that renders the job_detail template with test data, extract the contents of `<script>`, and check it with node. Or, more simply, I could use sed to replace `{{.Job.ID}}` with a number and check it with node.
First, let me check whether node is available.
Go side is green. Now let me verify the JavaScript is syntactically valid β check if node is available and extract the script:
Tool
π§ bash
{"command": "which node || which nodejs || echo \"no node\""}
Arguments
{"command": "which node || which nodejs || echo \"no node\""}
Result
no node
Thinking
Node isn't available. Let's write a small Go program that renders the job_detail template with test data, extracts the contents of `<script>`, replaces the template actions, and does a basic sanity check. Actually, as a better approach, how about writing a Go test that renders the page and checks the main JS fragments? The JS syntax can't be fully verified without a JS engine, but at least the following is possible:
1. Render the template (this will catch template syntax errors β Go template parsing is already done at server startup via `template.Must`).
2. Extract the script, do a brace/parenthesis balance check, and visually verify.
Actually, let's write a simple Go test that renders the job detail page for a running job and outputs the script block, then review it carefully. Or even simpler β let's render it with a small Go program and check the output.
Let's write a throwaway Go test in a temporary location... no, actually, I can just use `go run` with a small program that imports the web package. But the templates are unexported. Hmm.
Alternative: add a test to web_test.go that renders a running job's detail page and verifies the script contains the expected new logic (lazy creation, seq handling). This will be a useful regression test anyway. And for syntax checking, I can extract the script from the rendered output and do a rough balance check in Go... that's overkill.
Let's write a test that renders the page and asserts the presence of the main JS constructs:
```go
// TestJobDetailLiveScript verifies that the live view's script creates
// blocks lazily (only on the first non-whitespace delta) and enforces
// event sequence continuity, so that whitespace-only turns don't leave
// an empty block shell and dropped events trigger a fallback to the
// static page (issue #60).
func TestJobDetailLiveScript(t *testing.T) {
s, st := testServer(t)
ctx := context.Background()
if err := st.CreateJob(ctx, store.Job{ID: "job-1", EventKind: "issue:new", Agent: "leon", Owner: "acme", Repo: "widgets", IssueIndex: 1}); err != nil {
t.Fatal(err)
}
if err := st.MarkJobStarted(ctx, "job-1"); err != nil {
t.Fatal(err)
}
rr := httptest.NewRecorder()
s.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/jobs/job-1", nil))
if rr.Code != http.StatusOK {
t.Fatalf("expected 200, got %d: %s", rr.Code, rr.Body.String())
}
body := rr.Body.String()
for _, want := range []string{
`var lastSeq = 0;`,
`if (ev.type === "resync")`,
`if (b.buf.trim() === "") return;`, // lazy block creation
`if (b.body.textContent === "") b.body.parentElement.remove();`,
`ev.seq === lastSeq + 1`,
} {
if !strings.Contains(body, want) {
t.Fatalf("expected live script to contain %q", want)
}
}
}
```
Wait β does MarkJobStarted exist? In the scheduler: `s.store.MarkJobStarted(context.Background(), jobID)`. It exists. A running job β `.Live` is true β the script gets rendered.
Hmm, but wait: the testServer config has an Events mapping for issue:new β leon. The job's status after MarkJobStarted is running β Live = true. β
Let me check store.go to confirm the method name.
No node available. Let me check the store API and add a Go test that renders the live script and asserts the new logic is present (this also validates the template still parses):
Tool
π§ grep_search
{"context_after": 1, "query": "func \\(s \\*Store\\) MarkJob"}
Arguments
{"context_after": 1, "query": "func \\(s \\*Store\\) MarkJob"}
Result
/project/internal/store/store.go:243:func (s *Store) MarkJobStarted(ctx context.Context, id string) error {
/project/internal/store/store.go-244- _, err := s.db.ExecContext(ctx,
--
/project/internal/store/store.go:256:func (s *Store) MarkJobFinished(ctx context.Context, id string, status JobStatus, errMsg string) error {
/project/internal/store/store.go-257- _, err := s.db.ExecContext(ctx,
Thinking
Alright, let's add a test to web_test.go that renders the live script and verifies the new logic. I'll add it after TestJobEventsSequenceNumbers.
Tool
π§ edit_file
{"find": "// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved.", "path": "internal/web/web_test.go", "replace": "// TestJobDetailLiveScript verifies the live view's script creates\n// reasoning/content blocks lazily (on the first non-whitespace delta,\n// not on the *_start event) and enforces event-sequence continuity, so\n// a whitespace-only turn leaves no empty block shell and dropped\n// events trigger a fallback to the static page (issue #60).\nfunc TestJobDetailLiveScript(t *testing.T) {\n\ts, st := testServer(t)\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.MarkJobStarted(ctx, \"job-1\"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1\", nil))\n\tif rr.Code != http.StatusOK {\n\t\tt.Fatalf(\"expected 200, got %d: %s\", rr.Code, rr.Body.String())\n\t}\n\n\tbody := rr.Body.String()\n\n\tfor _, want := range []string{\n\t\t`var lastSeq = 0;`,\n\t\t`if (ev.type === \"resync\")`,\n\t\t`ev.seq === lastSeq + 1`,\n\t\t`if (b.buf.trim() === \"\") return;`,\n\t\t`if (b.body.textContent === \"\") b.body.parentElement.remove();`,\n\t} {\n\t\tif !strings.Contains(body, want) {\n\t\t\tt.Fatalf(\"expected live script to contain %q\", want)\n\t\t}\n\t}\n}\n\n// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved."}
Arguments
{"find": "// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved.", "path": "internal/web/web_test.go", "replace": "// TestJobDetailLiveScript verifies the live view's script creates\n// reasoning/content blocks lazily (on the first non-whitespace delta,\n// not on the *_start event) and enforces event-sequence continuity, so\n// a whitespace-only turn leaves no empty block shell and dropped\n// events trigger a fallback to the static page (issue #60).\nfunc TestJobDetailLiveScript(t *testing.T) {\n\ts, st := testServer(t)\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.MarkJobStarted(ctx, \"job-1\"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1\", nil))\n\tif rr.Code != http.StatusOK {\n\t\tt.Fatalf(\"expected 200, got %d: %s\", rr.Code, rr.Body.String())\n\t}\n\n\tbody := rr.Body.String()\n\n\tfor _, want := range []string{\n\t\t`var lastSeq = 0;`,\n\t\t`if (ev.type === \"resync\")`,\n\t\t`ev.seq === lastSeq + 1`,\n\t\t`if (b.buf.trim() === \"\") return;`,\n\t\t`if (b.body.textContent === \"\") b.body.parentElement.remove();`,\n\t} {\n\t\tif !strings.Contains(body, want) {\n\t\t\tt.Fatalf(\"expected live script to contain %q\", want)\n\t\t}\n\t}\n}\n\n// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content\n// blocks are rendered without the leading/trailing newlines the model\n// routinely emits: the block body uses white-space: pre-wrap, so those\n// would show up as visible blank lines inflating the block's height\n// (issue #53). Internal newlines must be preserved."}
Result
1 occurrences replaced
Thinking
Alright, let's run all the tests again, and also render the actual script to visually verify the JS syntax. Let me write a simple Go program that renders the job detail page and extracts the script... Actually, I can do it with a small Go test that dumps the script. Or even simpler, use `go run` in a temporary module? The template is private (unexported) inside the web package.
The simplest approach: temporarily add a test that writes out the rendered page, run it, check the script, then delete it. Or use `go test -run TestJobDetailLiveScript -v` with a temporary t.Logf... Let me create a temporary test file that dumps the script block to stdout, run it, review it, and then delete it.
Tool
π§ bash
{"command": "cd /project && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -5"}
Arguments
{"command": "cd /project && go test ./internal/livelog/ ./internal/web/ 2>&1 | tail -5"}
Result
ok github.com/abrander/zoo/internal/livelog (cached)
ok github.com/abrander/zoo/internal/web 1.527s
Thinking
All tests passed. Next, I'll extract the rendered JS and review it carefully. I'll create a temporary test that dumps the script block.
Now let me extract the rendered JS to review it carefully (temporary dump test):
Tool
π§ write_file
{"content": "package web\n\nimport (\n\t\"context\"\n\t\"net/http\"\n\t\"net/http/httptest\"\n\t\"regexp\"\n\t\"testing\"\n\n\t\"github.com/abrander/zoo/internal/store\"\n)\n\nfunc TestDumpLiveScript(t *testing.T) {\n\ts, st := testServer(t)\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.MarkJobStarted(ctx, \"job-1\"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1\", nil))\n\n\tre := regexp.MustCompile(`(?s)<script>(.*)</script>`)\n\tm := re.FindStringSubmatch(rr.Body.String())\n\tif len(m) != 2 {\n\t\tt.Fatal(\"no script found\")\n\t}\n\tt.Logf(\"SCRIPT_START\\n%s\\nSCRIPT_END\", m[1])\n}\n", "path": "internal/web/dump_test.go"}
Arguments
{"content": "package web\n\nimport (\n\t\"context\"\n\t\"net/http\"\n\t\"net/http/httptest\"\n\t\"regexp\"\n\t\"testing\"\n\n\t\"github.com/abrander/zoo/internal/store\"\n)\n\nfunc TestDumpLiveScript(t *testing.T) {\n\ts, st := testServer(t)\n\tctx := context.Background()\n\n\tif err := st.CreateJob(ctx, store.Job{ID: \"job-1\", EventKind: \"issue:new\", Agent: \"leon\", Owner: \"acme\", Repo: \"widgets\", IssueIndex: 1}); err != nil {\n\t\tt.Fatal(err)\n\t}\n\tif err := st.MarkJobStarted(ctx, \"job-1\"); err != nil {\n\t\tt.Fatal(err)\n\t}\n\n\trr := httptest.NewRecorder()\n\ts.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, \"/jobs/job-1\", nil))\n\n\tre := regexp.MustCompile(`(?s)<script>(.*)</script>`)\n\tm := re.FindStringSubmatch(rr.Body.String())\n\tif len(m) != 2 {\n\t\tt.Fatal(\"no script found\")\n\t}\n\tt.Logf(\"SCRIPT_START\\n%s\\nSCRIPT_END\", m[1])\n}\n", "path": "internal/web/dump_test.go"}
Result
OK
Thinking
Let's run this test and dump the script so we can verify that the JS is valid.
Tool
π§ bash
{"command": "cd /project && go test ./internal/web/ -run TestDumpLiveScript -v 2>&1 | sed -n '/SCRIPT_START/,/SCRIPT_END/p'"}
Arguments
{"command": "cd /project && go test ./internal/web/ -run TestDumpLiveScript -v 2>&1 | sed -n '/SCRIPT_START/,/SCRIPT_END/p'"}
Result
dump_test.go:32: SCRIPT_START
(function() {
var jobID = "job-1";
var log = document.getElementById("log");
var blocks = {
reasoning: {body: null, buf: ""},
content: {body: null, buf: ""}
};
var lastSeq = 0;
function nearBottom() {
return (window.innerHeight + window.scrollY) >= (document.body.offsetHeight - 80);
}
function newBlock(kind, label) {
var div = document.createElement("div");
div.className = "block block-" + kind;
if (label) {
var l = document.createElement("div");
l.className = "block-label";
l.textContent = label;
div.appendChild(l);
}
var body = document.createElement("div");
body.className = "block-body";
div.appendChild(body);
log.appendChild(div);
return body;
}
function newToolBlock(ev) {
var details = document.createElement("details");
details.className = "block block-tool" + (ev.error ? " block-tool-error" : "");
var summary = document.createElement("summary");
var badge = document.createElement("span");
badge.className = "tool-badge";
badge.textContent = "Tool";
var text = document.createElement("span");
text.className = "tool-summary-text";
var name = document.createElement("span");
name.className = "tool-name";
name.textContent = "π§ " + ev.name;
var preview = document.createElement("span");
preview.className = "tool-args-preview";
preview.textContent = ev.arguments;
text.appendChild(name);
text.appendChild(preview);
summary.appendChild(badge);
summary.appendChild(text);
details.appendChild(summary);
var body = document.createElement("div");
body.className = "block-body";
var argsLabel = document.createElement("div");
argsLabel.className = "tool-section-label";
argsLabel.textContent = "Arguments";
var argsPre = document.createElement("pre");
argsPre.textContent = ev.arguments;
var resultLabel = document.createElement("div");
resultLabel.className = "tool-section-label";
resultLabel.textContent = "Result";
var resultPre = document.createElement("pre");
resultPre.textContent = ev.result;
body.appendChild(argsLabel);
body.appendChild(argsPre);
body.appendChild(resultLabel);
body.appendChild(resultPre);
details.appendChild(body);
log.appendChild(details);
}
function resyncPage() {
es.close();
location.reload();
}
function onDelta(kind, delta) {
var b = blocks[kind];
if (b.body) {
b.body.textContent += delta;
return;
}
b.buf += delta;
if (b.buf.trim() === "") return;
b.body = newBlock(kind, kind === "reasoning" ? "Thinking" : null);
b.body.textContent = b.buf;
b.buf = "";
}
function onEnd(kind) {
var b = blocks[kind];
if (b.body) {
b.body.textContent = b.body.textContent.trim();
if (b.body.textContent === "") b.body.parentElement.remove();
b.body = null;
}
b.buf = "";
}
var es = new EventSource("/jobs/" + jobID + "/events");
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
if (ev.type === "resync") {
if (lastSeq !== 0 && (typeof ev.seq !== "number" || ev.seq !== lastSeq)) {
resyncPage();
}
return;
}
if (typeof ev.seq === "number") {
if (lastSeq === 0) {
lastSeq = ev.seq;
} else if (ev.seq === lastSeq + 1) {
lastSeq = ev.seq;
} else {
resyncPage();
return;
}
}
var shouldScroll = nearBottom();
switch (ev.type) {
case "reasoning_start":
blocks.reasoning.body = null;
blocks.reasoning.buf = "";
break;
case "reasoning_delta":
onDelta("reasoning", ev.text);
break;
case "reasoning_end":
onEnd("reasoning");
break;
case "content_start":
blocks.content.body = null;
blocks.content.buf = "";
break;
case "content_delta":
onDelta("content", ev.text);
break;
case "content_end":
onEnd("content");
break;
case "tool":
newToolBlock(ev);
break;
case "status":
resyncPage();
return;
}
if (shouldScroll) window.scrollTo(0, document.body.scrollHeight);
};
})();
SCRIPT_END
Thinking
The rendered JS looks correct (the extra blank lines are just where the template's comment lines got rendered β wait, no, that's not right. The template comments `// ...` are showing up as blank lines in the output? Let me check.
Looking at the output:
```
var jobID = "job-1";
var log = document.getElementById("log");
var blocks = {
```
Hmm, the comment block I wrote in the template:
```
// Per-block-kind rendering state: the open block's body (null
// while none is open) and a buffer of deltas received before the
// block was created. Model output routinely starts with
// newlines, and a block that ends up whitespace-only must not
// render at all (the static view drops those blocks too), so a
// block is created lazily on its first non-whitespace text
// instead of on the *_start event β that's what keeps a
// whitespace-only turn from flashing an empty block shell
// (issue #60).
```
is being rendered as blank lines! Why? Because in Go's html/template, `//` inside a `<script>` is... no wait. The problem is: html/template treats `<script>` content as JS context. Comments should pass through as-is. But... hmm, wait, looking more carefully:
```
var log = document.getElementById("log");
```
The comment lines are becoming blank. And in onDelta:
```
b.buf += delta;
if (b.buf.trim() === "") return;
b.body = newBlock(...)
```
The `// whitespace so far: no block yet` comment has disappeared (leaving a trailing space). And in onEnd:
```
if (b.body) {
b.body.textContent = b.body.textContent.trim();
```
The comment lines have become blank lines.
Wait, why would html/template strip `//` comments?? Ah! I got it. The template source is a Go raw string literal (backticks). The template contains `{{if .Live}}` and such. html/template parses `<script>` as a JS node and... no, it shouldn't strip comments.
Hmm, wait, let me look at the actual template source I wrote. I wrote:
```
// Per-block-kind rendering state: the open block's body (null
// while none is open) and a buffer of deltas received before the
// block was created. Model output routinely starts with
// newlines, and a block that ends up whitespace-only must not
// render at all (the static view drops those blocks too), so a
// block is created lazily on its first non-whitespace text
// instead of on the *_start event β that's what keeps a
// whitespace-only turn from flashing an empty block shell
// (issue #60).
```
Hmm, wait β is it possible that the edit_file tool or something stripped them? Let me check the actual file contents.
No wait, actually β I think I know what happened! html/template's JS parsing: in a `<script>` context, Go's html/template does tokenization. `//` comments are valid JS and should be preserved. But... hmm.
Hold on, let me look at the dump output more carefully:
```
var jobID = "job-1";
var log = document.getElementById("log");
```
There's a line with just spaces, then a line with just more spaces. The original comment lines had 6-space indentation + `// ...`. In the output, those lines have 14 spaces (the 8 from the template's indentation... hmm).
Wait, actually β could it be that html/template is treating `//` as the start of a URL or something? No...
Let me look at the actual file and check whether the comments are still there.
The JS logic is correct, but I notice my `//` comments in the script were stripped/blanked in the rendered output. Let me check the actual template file:
Tool
π§ bash
{"command": "cd /project && sed -n '880,905p' internal/web/templates.go | cat -A | head -30"}
Arguments
{"command": "cd /project && sed -n '880,905p' internal/web/templates.go | cat -A | head -30"}
Result
<script>$
(function() {$
var jobID = {{.Job.ID}};$
var log = document.getElementById("log");$
$
// Per-block-kind rendering state: the open block's body (null$
// while none is open) and a buffer of deltas received before the$
// block was created. Model output routinely starts with$
// newlines, and a block that ends up whitespace-only must not$
// render at all (the static view drops those blocks too), so a$
// block is created lazily on its first non-whitespace text$
// instead of on the *_start event M-bM-^@M-^T that's what keeps a$
// whitespace-only turn from flashing an empty block shell$
// (issue #60).$
var blocks = {$
reasoning: {body: null, buf: ""},$
content: {body: null, buf: ""}$
};$
$
// lastSeq is the sequence number of the last event rendered. The$
// server numbers every event per job and sends a "resync" marker$
// (with the hub's current number) when a subscription starts with$
// nothing to replay. Any break in the sequence M-bM-^@M-^T a gap from$
// dropped events, or a replay of an event we already rendered M-bM-^@M-^T$
// means the block state above can no longer be trusted, so we$
// fall back to the static page, which is always complete.$
Thinking
The comments exist in the template file. In other words, Go's `html/template` is stripping them out during rendering. Why?
Ahh, I got it! In Go's html/template, `<script>` content is parsed as JavaScript. And Go's JS tokenizer... hmm, actually I just remembered: Go's html/template has known behavior regarding comments in `<script>` β no wait, that's not it. Let me think.
Actually β I think the problem is something else. Let me look at the rendered output again:
```
var jobID = "job-1";
var log = document.getElementById("log");
```
The comment lines are rendered as whitespace-only lines (the indentation is preserved, but the `// ...` text is gone). Interesting β the indentation is preserved but the comment text is stripped.
Hmm, wait... is this because of the em dash `β` (M-bM-^@M-^T)? No, that's not it β the first comment block doesn't have an em dash... no wait, it does: "instead of on the *_start event β that's what keeps a".
Hmm, but the second comment in onDelta: `// whitespace so far: no block yet` β no em dash β is also stripped.
Let me test what html/template does with script comments. Actually, I just remembered! Go's html/template JS context: when it encounters `//` inside a script, it treats it as a comment and... no, it should preserve it.
Wait, wait. Let me look at the rendered output one more time, very carefully:
```
b.buf += delta;
if (b.buf.trim() === "") return;
b.body = newBlock(kind, kind === "reasoning" ? "Thinking" : null);
```
`return; ` has a trailing space β the comment `// whitespace so far: no block yet` was on the same line after `return;`. So the comment text was stripped, but the space before it was preserved.
And multi-line comments became empty lines (indentation preserved).
So html/template is stripping `//` comments inside `<script>`?! That seems strange... let me quickly verify with a minimal Go program.
Actually β oh. I think I get it now! The template is parsed with `template.New("").Parse(templates)`, and then `ExecuteTemplate(w, name, data)` is called. The `templates` constant contains all the template definitions. The job_detail template is... let me check how the templates are defined. `{{define "layout_head"}}` and so on. The script is inside the job_detail template.
Hmm, but why would comments be stripped? Let me write a minimal reproduction:
```go
package main
import (
"html/template"
"os"
)
func main() {
t := template.Must(template.New("x").Parse(`<script>
var a = 1; // comment
var b = 2;
</script>`))
t.Execute(os.Stdout, nil)
}
```
Let me run this and check.
The comments exist in the file but are being stripped during rendering. Let me try to reproduce this minimal behavior of html/template:
Tool
π§ bash
{"command": "cd /tmp && mkdir -p tpltest && cd tpltest && cat > main.go <<'EOF'\npackage main\n\nimport (\n\t\"html/template\"\n\t\"os\"\n)\n\nfunc main() {\n\tt := template.Must(template.New(\"x\").Parse(`<script>\nvar a = 1; // comment\nvar b = 2;\n/* block comment */\nvar c = 3;\n</script>`))\n\tt.Execute(os.Stdout, nil)\n}\nEOF\ngo mod init tpltest >/dev/null 2>&1; go run main.go"}
Arguments
{"command": "cd /tmp && mkdir -p tpltest && cd tpltest && cat > main.go <<'EOF'\npackage main\n\nimport (\n\t\"html/template\"\n\t\"os\"\n)\n\nfunc main() {\n\tt := template.Must(template.New(\"x\").Parse(`<script>\nvar a = 1; // comment\nvar b = 2;\n/* block comment */\nvar c = 3;\n</script>`))\n\tt.Execute(os.Stdout, nil)\n}\nEOF\ngo mod init tpltest >/dev/null 2>&1; go run main.go"}
Result
<script>
var a = 1;
var b = 2;
var c = 3;
</script>
Thinking
Confirmed! Go's `html/template` strips `//` comments and `/* */` comments inside `<script>` blocks. This is known behavior: html/template tokenizes JS and discards comments (treating them as ignorable tokens β in fact, the JS tokenizer in x/net/html/template/js has historically discarded comments).
In other words, the existing codebase already had this behavior β let me check the original script: it had a comment:
```js
case "reasoning_end":
// Model output routinely starts/ends with newlines; drop them
// so the finished block matches the static (trimmed) view.
if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();
```
That comment was also being stripped in the rendered output (a blank line). So this is existing behavior β comments inside the script don't reach the browser. My comments are harmless (they just don't get rendered), but they don't serve their documentation purpose on the client side either. That said, they do exist in the source.
Hmm, but this creates a visual problem: the rendered script has a bunch of blank lines where the comments used to be. It's a cosmetic issue, not a correctness one. The JS is functionally identical.
Options:
1. Leave the comments in the source (they document the code for developers reading templates.go) and accept the blank lines in the rendered output.
2. Remove the comments from the script.
The existing code had one comment (the reasoning_end one) and it was being stripped the same way. So option 1 is consistent with the existing style. The rendered blank lines are harmless (they're inside a script tag).
Actually, wait β let me double-check that the rendered JS is still valid with the blank lines: yes, blank lines in JS are fine.
But hmm, one thing to be careful about: could comment stripping break JS in edge cases? For example, if a string literal contains `//`β¦ html/template's JS tokenizer should handle strings correctly (it's a real tokenizer). The existing code has strings like "block block-" + kind β no problem. My code: `"/jobs/" + jobID + "/events"` β no `//` inside the stringβ¦ wait, what about URLs like "https://..."? There aren't any in the script. OK.
Actually, wait, there's a subtle danger: what if a string literal contains a sequence that the tokenizer misparses? The existing code has been working fine, and my additions don't introduce anything exotic. No problem.
So: the rendered JS is valid (comments β blank lines). My TestJobDetailLiveScript asserts on code fragments (not comments), so it passes.
Now, since I can't use node, let me do a more rigorous syntax sanity check of the rendered JS. I could write a small JS syntax checker in Go, butβ¦ that's overkill. Alternative: check the balance of curly braces, parentheses, and square brackets, and visually inspect the structure (already done above β it looks correct).
Let me do a quick balance check with a small Go program against the rendered script (stripping strings first to avoid counting braces inside strings). Actually, the rendered script has strings like "block block-" + kind, "π§ ", "Thinking", etc. β no braces inside strings. Let me just count the braces/parens in the raw script:
From the dump:
- (function() { ... })(); β balanced.
Let me run a quick count in Python (is python available?).
Confirmed β Go's `html/template` strips JS comments inside `<script>` (existing behavior; the old `reasoning_end` comment was also being stripped in the same way). The rendered JS is functionally fine (comments become blank lines). Let's do a syntax sanity check on the rendered script β checking the balance of curly braces / parentheses / square brackets:
Tool
π§ bash
{"command": "cd /project && go test ./internal/web/ -run TestDumpLiveScript -v 2>&1 | sed -n '/SCRIPT_START/,/SCRIPT_END/p' | sed '1d;$d' > /tmp/live.js && python3 - <<'EOF'\nimport re\nsrc = open('/tmp/live.js').read()\n# strip string literals and line comments (none left) before counting\nstripped = re.sub(r'\"(?:[^\"\\\\]|\\\\.)*\"', '\"\"', src)\nfor o, c in [('{','}'), ('(',')'), ('[',']')]:\n print(o, stripped.count(o), c, stripped.count(c), 'OK' if stripped.count(o)==stripped.count(c) else 'MISMATCH')\n# check semicolon-terminated statements look sane: count 'function' declarations\nprint('functions:', re.findall(r'function (\\w+)', stripped))\nEOF"}
Arguments
{"command": "cd /project && go test ./internal/web/ -run TestDumpLiveScript -v 2>&1 | sed -n '/SCRIPT_START/,/SCRIPT_END/p' | sed '1d;$d' > /tmp/live.js && python3 - <<'EOF'\nimport re\nsrc = open('/tmp/live.js').read()\n# strip string literals and line comments (none left) before counting\nstripped = re.sub(r'\"(?:[^\"\\\\]|\\\\.)*\"', '\"\"', src)\nfor o, c in [('{','}'), ('(',')'), ('[',']')]:\n print(o, stripped.count(o), c, stripped.count(c), 'OK' if stripped.count(o)==stripped.count(c) else 'MISMATCH')\n# check semicolon-terminated statements look sane: count 'function' declarations\nprint('functions:', re.findall(r'function (\\w+)', stripped))\nEOF"}
Result
{ 21 } 21 OK
( 73 ) 73 OK
[ 2 ] 2 OK
functions: ['nearBottom', 'newBlock', 'newToolBlock', 'resyncPage', 'onDelta', 'onEnd']
Thinking
The balance is fine. Next, let me simulate the client's state machine logic in Python and verify the behavior against the main scenarios:
1. Whitespace-only content turn β no block is created, no empty shell.
2. Normal content turn β block is created on the first non-whitespace delta, and trimmed on end.
3. Gap (missing seq) β resyncPage (reload).
4. Reconnect with empty buffer + resync ahead β reload.
5. Reconnect with empty buffer + resync in sync β no reload.
6. Reconnect with replay buffer that repairs (contiguous) β rendered, no reload.
7. Reconnect with duplicate replay β reload (safe fallback).
Let me write a Python simulation of the JS logic and run the scenarios.
Balance is good. Now let me simulate the client state machine in Python to verify the behavior across the key scenarios:
Tool
π§ bash
{"command": "cat > /tmp/sim.py <<'EOF'\n# Simulation of the rendered JS client logic (issue #60 fix).\nclass Client:\n def __init__(self):\n self.blocks = {\"reasoning\": {\"body\": None, \"buf\": \"\"},\n \"content\": {\"body\": None, \"buf\": \"\"}}\n self.lastSeq = 0\n self.dom = [] # list of (kind, text) blocks in DOM\n self.reloads = 0\n\n def resyncPage(self):\n self.reloads += 1\n\n def newBlock(self, kind, label):\n body = {\"kind\": kind, \"label\": label, \"text\": \"\"}\n self.dom.append(body)\n return body\n\n def onDelta(self, kind, delta):\n b = self.blocks[kind]\n if b[\"body\"]:\n b[\"body\"][\"text\"] += delta\n return\n b[\"buf\"] += delta\n if b[\"buf\"].strip() == \"\":\n return\n b[\"body\"] = self.newBlock(kind, \"Thinking\" if kind == \"reasoning\" else None)\n b[\"body\"][\"text\"] = b[\"buf\"]\n b[\"buf\"] = \"\"\n\n def onEnd(self, kind):\n b = self.blocks[kind]\n if b[\"body\"]:\n b[\"body\"][\"text\"] = b[\"body\"][\"text\"].strip()\n if b[\"body\"][\"text\"] == \"\":\n self.dom.remove(b[\"body\"])\n b[\"body\"] = None\n b[\"buf\"] = \"\"\n\n def onmessage(self, ev):\n if ev[\"type\"] == \"resync\":\n if self.lastSeq != 0 and (not isinstance(ev.get(\"seq\"), int) or ev[\"seq\"] != self.lastSeq):\n self.resyncPage()\n return\n if isinstance(ev.get(\"seq\"), int):\n if self.lastSeq == 0:\n self.lastSeq = ev[\"seq\"]\n elif ev[\"seq\"] == self.lastSeq + 1:\n self.lastSeq = ev[\"seq\"]\n else:\n self.resyncPage()\n return\n t = ev[\"type\"]\n if t == \"reasoning_start\":\n self.blocks[\"reasoning\"] = {\"body\": None, \"buf\": \"\"}\n elif t == \"reasoning_delta\":\n self.onDelta(\"reasoning\", ev[\"text\"])\n elif t == \"reasoning_end\":\n self.onEnd(\"reasoning\")\n elif t == \"content_start\":\n self.blocks[\"content\"] = {\"body\": None, \"buf\": \"\"}\n elif t == \"content_delta\":\n self.onDelta(\"content\", ev[\"text\"])\n elif t == \"content_end\":\n self.onEnd(\"content\")\n elif t == \"tool\":\n pass\n elif t == \"status\":\n self.resyncPage()\n return\n\ndef feed(c, events):\n for ev in events:\n c.onmessage(ev)\n\ndef check(name, cond):\n print((\"PASS\" if cond else \"FAIL\"), name)\n return cond\n\nok = True\n\n# 1. Whitespace-only content turn: no block shell at all.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"\\n\"},\n {\"type\":\"content_end\",\"seq\":3}])\nok &= check(\"whitespace-only turn leaves no block\", c.dom == [] and c.reloads == 0)\n\n# 2. Normal content turn with leading/trailing newlines: one trimmed block.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"\\n\"},\n {\"type\":\"content_delta\",\"seq\":3,\"text\":\"Let me check the tools package\"},\n {\"type\":\"content_delta\",\"seq\":4,\"text\":\" (for testability).\"},\n {\"type\":\"content_end\",\"seq\":5}])\nok &= check(\"normal turn -> one trimmed block\",\n c.dom == [{\"kind\":\"content\",\"label\":None,\"text\":\"Let me check the tools package (for testability).\"}] and c.reloads == 0)\n\n# 3. Gap: dropped delta (seq jump) -> reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"He\"},\n # seq 3 dropped\n {\"type\":\"content_delta\",\"seq\":4,\"text\":\"llo\"},\n {\"type\":\"content_end\",\"seq\":5}])\nok &= check(\"gap triggers reload\", c.reloads == 1)\n\n# 4. Reconnect, empty buffer, hub ahead -> resync triggers reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}])\nfeed(c, [{\"type\":\"resync\",\"seq\":7}])\nok &= check(\"resync ahead of lastSeq triggers reload\", c.reloads == 1)\n\n# 5. Reconnect, empty buffer, hub exactly at lastSeq -> in sync, no reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}])\nfeed(c, [{\"type\":\"resync\",\"seq\":2}])\nok &= check(\"resync in sync does not reload\", c.reloads == 0)\n\n# 6. Fresh page joins mid-replay (buffered block): renders, no reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":10},\n {\"type\":\"content_delta\",\"seq\":11,\"text\":\"\\n\"},\n {\"type\":\"content_delta\",\"seq\":12,\"text\":\"Hello\"},\n {\"type\":\"content_end\",\"seq\":13}])\nok &= check(\"fresh page renders replayed block\",\n c.dom == [{\"kind\":\"content\",\"label\":None,\"text\":\"Hello\"}] and c.reloads == 0)\n\n# 7. Reconnect with duplicate replay (already rendered) -> safe reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}])\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}])\nok &= check(\"duplicate replay triggers reload (safe)\", c.reloads == 1)\n\n# 8. Reconnect where replay heals: in-flight events still in buffer, contiguous.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"He\"}])\n# connection dropped; buffer replays from checkpoint (seq 1) incl. in-flight:\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"He\"},\n {\"type\":\"content_delta\",\"seq\":3,\"text\":\"llo\"},\n {\"type\":\"content_end\",\"seq\":4}])\nok &= check(\"healing replay: first dup triggers reload (safe, no corruption)\", c.reloads == 1)\n\n# 9. Reasoning lazy creation + trim.\nc = Client()\nfeed(c, [{\"type\":\"reasoning_start\",\"seq\":1},\n {\"type\":\"reasoning_delta\",\"seq\":2,\"text\":\" \\n\"},\n {\"type\":\"reasoning_delta\",\"seq\":3,\"text\":\"Thinking...\"},\n {\"type\":\"reasoning_end\",\"seq\":4}])\nok &= check(\"reasoning block lazy-created and trimmed\",\n c.dom == [{\"kind\":\"reasoning\",\"label\":\"Thinking\",\"text\":\"Thinking...\"}] and c.reloads == 0)\n\n# 10. Tool event mid-stream does not disturb block state.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"Using a tool\"},\n {\"type\":\"tool\",\"seq\":3,\"name\":\"bash\"},\n {\"type\":\"content_end\",\"seq\":4}])\nok &= check(\"tool event coexists with open block\",\n c.dom == [{\"kind\":\"content\",\"label\":None,\"text\":\"Using a tool\"}] and c.reloads == 0)\n\n# 11. status event -> reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"x\"}])\nfeed(c, [{\"type\":\"status\",\"seq\":3,\"status\":\"done\"}])\nok &= check(\"status triggers reload\", c.reloads == 1)\n\n# 12. Two consecutive turns: blocks close and reopen cleanly.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"First\"},\n {\"type\":\"content_end\",\"seq\":3},\n {\"type\":\"content_start\",\"seq\":4},\n {\"type\":\"content_delta\",\"seq\":5,\"text\":\"Second\"},\n {\"type\":\"content_end\",\"seq\":6}])\nok &= check(\"consecutive turns -> two blocks\",\n [b[\"text\"] for b in c.dom] == [\"First\", \"Second\"] and c.reloads == 0)\n\nprint(\"ALL PASS\" if ok else \"SOME FAILED\")\nEOF\npython3 /tmp/sim.py"}
Arguments
{"command": "cat > /tmp/sim.py <<'EOF'\n# Simulation of the rendered JS client logic (issue #60 fix).\nclass Client:\n def __init__(self):\n self.blocks = {\"reasoning\": {\"body\": None, \"buf\": \"\"},\n \"content\": {\"body\": None, \"buf\": \"\"}}\n self.lastSeq = 0\n self.dom = [] # list of (kind, text) blocks in DOM\n self.reloads = 0\n\n def resyncPage(self):\n self.reloads += 1\n\n def newBlock(self, kind, label):\n body = {\"kind\": kind, \"label\": label, \"text\": \"\"}\n self.dom.append(body)\n return body\n\n def onDelta(self, kind, delta):\n b = self.blocks[kind]\n if b[\"body\"]:\n b[\"body\"][\"text\"] += delta\n return\n b[\"buf\"] += delta\n if b[\"buf\"].strip() == \"\":\n return\n b[\"body\"] = self.newBlock(kind, \"Thinking\" if kind == \"reasoning\" else None)\n b[\"body\"][\"text\"] = b[\"buf\"]\n b[\"buf\"] = \"\"\n\n def onEnd(self, kind):\n b = self.blocks[kind]\n if b[\"body\"]:\n b[\"body\"][\"text\"] = b[\"body\"][\"text\"].strip()\n if b[\"body\"][\"text\"] == \"\":\n self.dom.remove(b[\"body\"])\n b[\"body\"] = None\n b[\"buf\"] = \"\"\n\n def onmessage(self, ev):\n if ev[\"type\"] == \"resync\":\n if self.lastSeq != 0 and (not isinstance(ev.get(\"seq\"), int) or ev[\"seq\"] != self.lastSeq):\n self.resyncPage()\n return\n if isinstance(ev.get(\"seq\"), int):\n if self.lastSeq == 0:\n self.lastSeq = ev[\"seq\"]\n elif ev[\"seq\"] == self.lastSeq + 1:\n self.lastSeq = ev[\"seq\"]\n else:\n self.resyncPage()\n return\n t = ev[\"type\"]\n if t == \"reasoning_start\":\n self.blocks[\"reasoning\"] = {\"body\": None, \"buf\": \"\"}\n elif t == \"reasoning_delta\":\n self.onDelta(\"reasoning\", ev[\"text\"])\n elif t == \"reasoning_end\":\n self.onEnd(\"reasoning\")\n elif t == \"content_start\":\n self.blocks[\"content\"] = {\"body\": None, \"buf\": \"\"}\n elif t == \"content_delta\":\n self.onDelta(\"content\", ev[\"text\"])\n elif t == \"content_end\":\n self.onEnd(\"content\")\n elif t == \"tool\":\n pass\n elif t == \"status\":\n self.resyncPage()\n return\n\ndef feed(c, events):\n for ev in events:\n c.onmessage(ev)\n\ndef check(name, cond):\n print((\"PASS\" if cond else \"FAIL\"), name)\n return cond\n\nok = True\n\n# 1. Whitespace-only content turn: no block shell at all.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"\\n\"},\n {\"type\":\"content_end\",\"seq\":3}])\nok &= check(\"whitespace-only turn leaves no block\", c.dom == [] and c.reloads == 0)\n\n# 2. Normal content turn with leading/trailing newlines: one trimmed block.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"\\n\"},\n {\"type\":\"content_delta\",\"seq\":3,\"text\":\"Let me check the tools package\"},\n {\"type\":\"content_delta\",\"seq\":4,\"text\":\" (for testability).\"},\n {\"type\":\"content_end\",\"seq\":5}])\nok &= check(\"normal turn -> one trimmed block\",\n c.dom == [{\"kind\":\"content\",\"label\":None,\"text\":\"Let me check the tools package (for testability).\"}] and c.reloads == 0)\n\n# 3. Gap: dropped delta (seq jump) -> reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"He\"},\n # seq 3 dropped\n {\"type\":\"content_delta\",\"seq\":4,\"text\":\"llo\"},\n {\"type\":\"content_end\",\"seq\":5}])\nok &= check(\"gap triggers reload\", c.reloads == 1)\n\n# 4. Reconnect, empty buffer, hub ahead -> resync triggers reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}])\nfeed(c, [{\"type\":\"resync\",\"seq\":7}])\nok &= check(\"resync ahead of lastSeq triggers reload\", c.reloads == 1)\n\n# 5. Reconnect, empty buffer, hub exactly at lastSeq -> in sync, no reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}])\nfeed(c, [{\"type\":\"resync\",\"seq\":2}])\nok &= check(\"resync in sync does not reload\", c.reloads == 0)\n\n# 6. Fresh page joins mid-replay (buffered block): renders, no reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":10},\n {\"type\":\"content_delta\",\"seq\":11,\"text\":\"\\n\"},\n {\"type\":\"content_delta\",\"seq\":12,\"text\":\"Hello\"},\n {\"type\":\"content_end\",\"seq\":13}])\nok &= check(\"fresh page renders replayed block\",\n c.dom == [{\"kind\":\"content\",\"label\":None,\"text\":\"Hello\"}] and c.reloads == 0)\n\n# 7. Reconnect with duplicate replay (already rendered) -> safe reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}])\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"hi\"}])\nok &= check(\"duplicate replay triggers reload (safe)\", c.reloads == 1)\n\n# 8. Reconnect where replay heals: in-flight events still in buffer, contiguous.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"He\"}])\n# connection dropped; buffer replays from checkpoint (seq 1) incl. in-flight:\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"He\"},\n {\"type\":\"content_delta\",\"seq\":3,\"text\":\"llo\"},\n {\"type\":\"content_end\",\"seq\":4}])\nok &= check(\"healing replay: first dup triggers reload (safe, no corruption)\", c.reloads == 1)\n\n# 9. Reasoning lazy creation + trim.\nc = Client()\nfeed(c, [{\"type\":\"reasoning_start\",\"seq\":1},\n {\"type\":\"reasoning_delta\",\"seq\":2,\"text\":\" \\n\"},\n {\"type\":\"reasoning_delta\",\"seq\":3,\"text\":\"Thinking...\"},\n {\"type\":\"reasoning_end\",\"seq\":4}])\nok &= check(\"reasoning block lazy-created and trimmed\",\n c.dom == [{\"kind\":\"reasoning\",\"label\":\"Thinking\",\"text\":\"Thinking...\"}] and c.reloads == 0)\n\n# 10. Tool event mid-stream does not disturb block state.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"Using a tool\"},\n {\"type\":\"tool\",\"seq\":3,\"name\":\"bash\"},\n {\"type\":\"content_end\",\"seq\":4}])\nok &= check(\"tool event coexists with open block\",\n c.dom == [{\"kind\":\"content\",\"label\":None,\"text\":\"Using a tool\"}] and c.reloads == 0)\n\n# 11. status event -> reload.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1}, {\"type\":\"content_delta\",\"seq\":2,\"text\":\"x\"}])\nfeed(c, [{\"type\":\"status\",\"seq\":3,\"status\":\"done\"}])\nok &= check(\"status triggers reload\", c.reloads == 1)\n\n# 12. Two consecutive turns: blocks close and reopen cleanly.\nc = Client()\nfeed(c, [{\"type\":\"content_start\",\"seq\":1},\n {\"type\":\"content_delta\",\"seq\":2,\"text\":\"First\"},\n {\"type\":\"content_end\",\"seq\":3},\n {\"type\":\"content_start\",\"seq\":4},\n {\"type\":\"content_delta\",\"seq\":5,\"text\":\"Second\"},\n {\"type\":\"content_end\",\"seq\":6}])\nok &= check(\"consecutive turns -> two blocks\",\n [b[\"text\"] for b in c.dom] == [\"First\", \"Second\"] and c.reloads == 0)\n\nprint(\"ALL PASS\" if ok else \"SOME FAILED\")\nEOF\npython3 /tmp/sim.py"}
Result
PASS whitespace-only turn leaves no block
PASS normal turn -> one trimmed block
FAIL gap triggers reload
PASS resync ahead of lastSeq triggers reload
PASS resync in sync does not reload
PASS fresh page renders replayed block
FAIL duplicate replay triggers reload (safe)
FAIL healing replay: first dup triggers reload (safe, no corruption)
PASS reasoning block lazy-created and trimmed
PASS tool event coexists with open block
PASS status triggers reload
PASS consecutive turns -> two blocks
SOME FAILED
Thinking
3 failures β let me analyze:
**Test 3 (gap triggers reload):**
```python
feed(c, [{"type":"content_start","seq":1},
{"type":"content_delta","seq":2,"text":"He"},
# seq 3 dropped
{"type":"content_delta","seq":4,"text":"llo"},
{"type":"content_end","seq":5}])
```
Expected: reload on seq 4 (gap). But it failed. Why?
Ah, wait β I found a bug in my simulationβ¦ no wait, let me trace through:
- seq 1: lastSeq=0 β lastSeq=1. Render start.
- seq 2: == lastSeq+1 β lastSeq=2. Render delta "He".
- seq 4: lastSeq=2, 4 != 3 β resyncPage β reloads=1. β Should pass!
Hmm, wait, why did it fail? Let me check the condition: `c.reloads == 1`. After seq 4 β reload. Then seq 5: `isinstance(ev.get("seq"), int)` β lastSeq=2, 5 != 3 β resyncPage again β reloads=2! So reloads == 2, not 1. My test's assertion was wrong β the client keeps processing subsequent events after a "reload" (in reality the page would be reloaded and the JS state would be reset, but in the simulation it continues). So the assertion should be `c.reloads >= 1`.
**Test 7 (duplicate replay):**
```python
feed(c, [{"type":"content_start","seq":1}, {"type":"content_delta","seq":2,"text":"hi"}])
feed(c, [{"type":"content_start","seq":1}, {"type":"content_delta","seq":2,"text":"hi"}])
```
- First feed: lastSeq=2.
- Second feed: seq 1: lastSeq=2, 1 != 3 β resyncPage β reloads=1. seq 2: 2 != 3 β resyncPage β reloads=2.
So reloads == 2, not 1. Same issue β the assertion should be >= 1.
**Test 8 (healing replay):**
```python
feed(c, [{"type":"content_start","seq":1}, {"type":"content_delta","seq":2,"text":"He"}])
feed(c, [{"type":"content_start","seq":1}, ...])
```
- First feed: lastSeq=2, DOM has a block with "He".
- Second feed: seq 1 β 1 != 3 β reload (1). seq 2 β 2 != 3 β reload (2). seq 3 β 3 == 3 β lastSeq=3, render "llo" (appended to the existing block body β "Hello"). seq 4 β end β trim.
- reloads == 2, not 1. Assertion `c.reloads == 1` fails.
So all 3 "failures" are due to my simulation's assertion counting multiple resyncPage calls (in the real browser, location.reload() would reset everything after the first call). The important behavior β that a reload is triggered β is correct. Let me fix the assertions to `>= 1` and re-run.
Actually, this reveals a real (minor) consideration: in the real browser, `location.reload()` is asynchronous β the JS keeps executing subsequent events until the page actually unloads, and each anomalous event calls resyncPage again (es.close() + location.reload() again). es.close() is idempotent, and calling location.reload() multiple times is harmless (the first one takes effect). So this is fine.
Let me fix the simulation's assertions.
The 3 "failures" are artifacts of the simulation: after the first `resyncPage()`, the actual browser reloads (state reset), but my simulation keeps feeding events, so `resyncPage` fires again on each subsequent anomalous event. The reload *is* triggered β my assertion was just too strict. Fixing the assertion:
Tool
π§ bash
{"command": "cd /tmp && sed -i 's/ok &= check(\"gap triggers reload\", c.reloads == 1)/ok \\&= check(\"gap triggers reload\", c.reloads >= 1)/; s/ok &= check(\"duplicate replay triggers reload (safe)\", c.reloads == 1)/ok \\&= check(\"duplicate replay triggers reload (safe)\", c.reloads >= 1)/; s/ok &= check(\"healing replay: first dup triggers reload (safe, no corruption)\", c.reloads == 1)/ok \\&= check(\"healing replay: first dup triggers reload (safe, no corruption)\", c.reloads >= 1)/' sim.py && python3 sim.py"}
Arguments
{"command": "cd /tmp && sed -i 's/ok &= check(\"gap triggers reload\", c.reloads == 1)/ok \\&= check(\"gap triggers reload\", c.reloads >= 1)/; s/ok &= check(\"duplicate replay triggers reload (safe)\", c.reloads == 1)/ok \\&= check(\"duplicate replay triggers reload (safe)\", c.reloads >= 1)/; s/ok &= check(\"healing replay: first dup triggers reload (safe, no corruption)\", c.reloads == 1)/ok \\&= check(\"healing replay: first dup triggers reload (safe, no corruption)\", c.reloads >= 1)/' sim.py && python3 sim.py"}
Result
PASS whitespace-only turn leaves no block
PASS normal turn -> one trimmed block
PASS gap triggers reload
PASS resync ahead of lastSeq triggers reload
PASS resync in sync does not reload
PASS fresh page renders replayed block
PASS duplicate replay triggers reload (safe)
PASS healing replay: first dup triggers reload (safe, no corruption)
PASS reasoning block lazy-created and trimmed
PASS tool event coexists with open block
PASS status triggers reload
PASS consecutive turns -> two blocks
ALL PASS
Thinking
All 12 scenarios pass. The client logic is correct.
Next, clean up the temporary dump test and run the full test suite. After that, review the entire diff.
All scenarios pass. Now remove the temporary dump test and run the full test suite:
Tool
π§ remove_file
{"path": "internal/web/dump_test.go"}
Arguments
{"path": "internal/web/dump_test.go"}
Result
File removed successfully
Thinking
Next, I'll run the full test suite (excluding the Docker integration tests that require a Docker daemon β let me check which tests require Docker).
Tool
π§ bash
{"command": "cd /project && go build ./... && go vet ./... && go test ./... 2>&1 | tail -15"}
Arguments
{"command": "cd /project && go build ./... && go vet ./... && go test ./... 2>&1 | tail -15"}
Result
? github.com/abrander/zoo/cmd/zoo [no test files]
ok github.com/abrander/zoo/internal/agentrun 0.004s
ok github.com/abrander/zoo/internal/config 0.006s
ok github.com/abrander/zoo/internal/forgejo 1.241s
ok github.com/abrander/zoo/internal/livelog (cached)
ok github.com/abrander/zoo/internal/llm 0.003s
ok github.com/abrander/zoo/internal/scheduler 2.756s
ok github.com/abrander/zoo/internal/store 1.668s
ok github.com/abrander/zoo/internal/tools 0.003s
ok github.com/abrander/zoo/internal/web (cached)
Thinking
All tests passed. Let me check the final diff to make sure everything is clean and consistent.
All green. Let me review the complete diff:
Tool
π§ bash
{"command": "cd /project && git diff --stat && git diff"}
Arguments
{"command": "cd /project && git diff --stat && git diff"}
Result
internal/livelog/hub.go | 42 +++++++++++++++----
internal/livelog/hub_test.go | 70 ++++++++++++++++++++++++++++---
internal/web/templates.go | 99 +++++++++++++++++++++++++++++++++++++-------
internal/web/web.go | 15 ++++++-
internal/web/web_test.go | 86 ++++++++++++++++++++++++++++++++++++++
5 files changed, 283 insertions(+), 29 deletions(-)
diff --git a/internal/livelog/hub.go b/internal/livelog/hub.go
index 8f58356..20274f5 100644
--- a/internal/livelog/hub.go
+++ b/internal/livelog/hub.go
@@ -18,10 +18,22 @@ const (
ContentEnd Type = "content_end"
Tool Type = "tool"
Status Type = "status"
+
+ // Resync is never published through Publish; the web layer sends it
+ // as the first message of a subscription that starts with an empty
+ // replay buffer, carrying the job's current sequence number, so the
+ // client can tell whether it missed events since its last
+ // (re)connect.
+ Resync Type = "resync"
)
type Event struct {
- Type Type `json:"type"`
+ Type Type `json:"type"`
+ // Seq is the job's monotonically increasing sequence number,
+ // assigned by Publish. Clients use it to detect dropped events
+ // (gaps in the sequence) and fall back to the static page, which
+ // is always complete.
+ Seq uint64 `json:"seq,omitempty"`
Text string `json:"text,omitempty"`
Name string `json:"name,omitempty"`
Arguments string `json:"arguments,omitempty"`
@@ -32,8 +44,11 @@ type Event struct {
// subChanBuffer bounds how many events a slow subscriber can lag behind
// by before new events are dropped for it. Generous for a single-user
-// local dashboard; a dropped event just means a subscriber's browser
-// tab misses a chunk and catches up on the next one, never a hang.
+// local dashboard. A dropped event is recoverable rather than silent:
+// every event carries a monotonically increasing Seq, so a client that
+// misses one detects the gap in the sequence and falls back to the
+// static page instead of rendering a desynced (empty or truncated)
+// block.
const subChanBuffer = 256
// maxBufferedEvents caps the per-job replay buffer as a safety net
@@ -45,6 +60,7 @@ type stream struct {
mu sync.Mutex
buf []Event
subs map[chan Event]struct{}
+ seq uint64
}
// Hub fans out per-job Events to any number of live subscribers.
@@ -72,13 +88,17 @@ func (h *Hub) get(jobID string) *stream {
// Publish appends ev to jobID's replay buffer and fans it out to every
// current subscriber. Never blocks: a subscriber whose channel is full
-// simply misses this event.
+// simply misses this event (the client detects the resulting gap in
+// Seq and falls back to the static page).
func (h *Hub) Publish(jobID string, ev Event) {
s := h.get(jobID)
s.mu.Lock()
defer s.mu.Unlock()
+ s.seq++
+ ev.Seq = s.seq
+
s.buf = append(s.buf, ev)
if len(s.buf) > maxBufferedEvents {
s.buf = s.buf[len(s.buf)-maxBufferedEvents:]
@@ -107,16 +127,20 @@ func (h *Hub) Checkpoint(jobID string) {
}
// Subscribe returns the events currently buffered for jobID (i.e. not
-// yet checkpointed) plus a channel of everything published from this
-// point on. The returned cancel func must be called when the caller is
-// done reading, to unregister and close the channel.
-func (h *Hub) Subscribe(jobID string) (buffered []Event, ch <-chan Event, cancel func()) {
+// yet checkpointed), the job's current sequence number (the Seq of the
+// most recently published event, 0 if none), and a channel of
+// everything published from this point on. The buffer snapshot and the
+// seq are taken under one lock, so the seq is always >= every buffered
+// event's Seq. The returned cancel func must be called when the caller
+// is done reading, to unregister and close the channel.
+func (h *Hub) Subscribe(jobID string) (buffered []Event, seq uint64, ch <-chan Event, cancel func()) {
s := h.get(jobID)
s.mu.Lock()
defer s.mu.Unlock()
buffered = append([]Event(nil), s.buf...)
+ seq = s.seq
c := make(chan Event, subChanBuffer)
s.subs[c] = struct{}{}
@@ -135,7 +159,7 @@ func (h *Hub) Subscribe(jobID string) (buffered []Event, ch <-chan Event, cancel
})
}
- return buffered, c, cancelFn
+ return buffered, seq, c, cancelFn
}
// Close publishes a terminal Status event, disconnects every current
diff --git a/internal/livelog/hub_test.go b/internal/livelog/hub_test.go
index 2c980cc..07a9060 100644
--- a/internal/livelog/hub_test.go
+++ b/internal/livelog/hub_test.go
@@ -28,7 +28,7 @@ func TestSubscribeReplaysBufferedEvents(t *testing.T) {
h.Publish("job-1", Event{Type: ContentStart})
h.Publish("job-1", Event{Type: ContentDelta, Text: "hi"})
- buffered, ch, cancel := h.Subscribe("job-1")
+ buffered, seq, ch, cancel := h.Subscribe("job-1")
defer cancel()
if len(buffered) != 2 {
@@ -37,6 +37,9 @@ func TestSubscribeReplaysBufferedEvents(t *testing.T) {
if buffered[1].Text != "hi" {
t.Fatalf("unexpected buffered event: %+v", buffered[1])
}
+ if seq != 2 {
+ t.Fatalf("expected current seq 2, got %d", seq)
+ }
h.Publish("job-1", Event{Type: ContentDelta, Text: " there"})
@@ -44,6 +47,63 @@ func TestSubscribeReplaysBufferedEvents(t *testing.T) {
if ev.Text != " there" {
t.Fatalf("expected live delta %q, got %+v", " there", ev)
}
+ if ev.Seq != 3 {
+ t.Fatalf("expected live delta to carry seq 3, got %+v", ev)
+ }
+}
+
+// TestPublishAssignsMonotonicSeqs verifies that every published event
+// gets the job's next sequence number, and that seqs are per-job: a
+// client uses them to detect dropped events (gaps) and fall back to
+// the static page (issue #60).
+func TestPublishAssignsMonotonicSeqs(t *testing.T) {
+ h := NewHub()
+
+ h.Publish("job-1", Event{Type: ContentStart})
+ h.Publish("job-1", Event{Type: ContentDelta, Text: "hi"})
+ h.Publish("job-2", Event{Type: ContentStart})
+
+ buffered, seq, _, cancel := h.Subscribe("job-1")
+ defer cancel()
+
+ if seq != 2 {
+ t.Fatalf("expected job-1's current seq to be 2, got %d", seq)
+ }
+ for i, ev := range buffered {
+ if ev.Seq != uint64(i+1) {
+ t.Fatalf("expected buffered event %d to have seq %d, got %+v", i, i+1, ev)
+ }
+ }
+
+ // job-2 has its own seq space, independent of job-1's.
+ buffered2, seq2, _, cancel2 := h.Subscribe("job-2")
+ defer cancel2()
+
+ if seq2 != 1 || len(buffered2) != 1 || buffered2[0].Seq != 1 {
+ t.Fatalf("expected job-2 to have its own seq space, got seq=%d buffered=%+v", seq2, buffered2)
+ }
+}
+
+// TestSubscribeSeqTracksLatestPublished verifies that the seq returned
+// by Subscribe is 0 for a fresh job and follows publishes, so the web
+// layer can send a resync marker that lets a reconnecting client tell
+// whether it missed events.
+func TestSubscribeSeqTracksLatestPublished(t *testing.T) {
+ h := NewHub()
+
+ _, seq, _, cancel := h.Subscribe("job-1")
+ defer cancel()
+
+ if seq != 0 {
+ t.Fatalf("expected seq 0 for a fresh job, got %d", seq)
+ }
+
+ h.Publish("job-1", Event{Type: ContentDelta, Text: "hi"})
+
+ _, seq, _, _ = h.Subscribe("job-1")
+ if seq != 1 {
+ t.Fatalf("expected seq 1 after one publish, got %d", seq)
+ }
}
func TestCheckpointClearsBuffer(t *testing.T) {
@@ -53,7 +113,7 @@ func TestCheckpointClearsBuffer(t *testing.T) {
h.Publish("job-1", Event{Type: ContentDelta, Text: "hi"})
h.Checkpoint("job-1")
- buffered, _, cancel := h.Subscribe("job-1")
+ buffered, _, _, cancel := h.Subscribe("job-1")
defer cancel()
if len(buffered) != 0 {
@@ -64,7 +124,7 @@ func TestCheckpointClearsBuffer(t *testing.T) {
func TestCloseTerminatesSubscribers(t *testing.T) {
h := NewHub()
- _, ch, cancel := h.Subscribe("job-1")
+ _, _, ch, cancel := h.Subscribe("job-1")
defer cancel()
h.Close("job-1")
@@ -90,7 +150,7 @@ func TestSubscribeAfterCloseGetsEmptyBuffer(t *testing.T) {
h.Publish("job-1", Event{Type: ContentDelta, Text: "hi"})
h.Close("job-1")
- buffered, ch, cancel := h.Subscribe("job-1")
+ buffered, _, ch, cancel := h.Subscribe("job-1")
defer cancel()
if len(buffered) != 0 {
@@ -107,7 +167,7 @@ func TestSubscribeAfterCloseGetsEmptyBuffer(t *testing.T) {
func TestCancelUnregistersSubscriber(t *testing.T) {
h := NewHub()
- _, ch, cancel := h.Subscribe("job-1")
+ _, _, ch, cancel := h.Subscribe("job-1")
cancel()
select {
diff --git a/internal/web/templates.go b/internal/web/templates.go
index c64e61b..e2f336f 100644
--- a/internal/web/templates.go
+++ b/internal/web/templates.go
@@ -881,8 +881,29 @@ const templates = `
(function() {
var jobID = {{.Job.ID}};
var log = document.getElementById("log");
- var reasoningBody = null;
- var contentBody = null;
+
+ // Per-block-kind rendering state: the open block's body (null
+ // while none is open) and a buffer of deltas received before the
+ // block was created. Model output routinely starts with
+ // newlines, and a block that ends up whitespace-only must not
+ // render at all (the static view drops those blocks too), so a
+ // block is created lazily on its first non-whitespace text
+ // instead of on the *_start event β that's what keeps a
+ // whitespace-only turn from flashing an empty block shell
+ // (issue #60).
+ var blocks = {
+ reasoning: {body: null, buf: ""},
+ content: {body: null, buf: ""}
+ };
+
+ // lastSeq is the sequence number of the last event rendered. The
+ // server numbers every event per job and sends a "resync" marker
+ // (with the hub's current number) when a subscription starts with
+ // nothing to replay. Any break in the sequence β a gap from
+ // dropped events, or a replay of an event we already rendered β
+ // means the block state above can no longer be trusted, so we
+ // fall back to the static page, which is always complete.
+ var lastSeq = 0;
function nearBottom() {
return (window.innerHeight + window.scrollY) >= (document.body.offsetHeight - 80);
@@ -954,41 +975,91 @@ const templates = `
log.appendChild(details);
}
+ function resyncPage() {
+ es.close();
+ location.reload();
+ }
+
+ function onDelta(kind, delta) {
+ var b = blocks[kind];
+ if (b.body) {
+ b.body.textContent += delta;
+ return;
+ }
+ b.buf += delta;
+ if (b.buf.trim() === "") return; // whitespace so far: no block yet
+ b.body = newBlock(kind, kind === "reasoning" ? "Thinking" : null);
+ b.body.textContent = b.buf;
+ b.buf = "";
+ }
+
+ function onEnd(kind) {
+ var b = blocks[kind];
+ if (b.body) {
+ // Model output routinely starts/ends with newlines; drop them
+ // so the finished block matches the static (trimmed) view,
+ // and drop the block entirely if nothing is left.
+ b.body.textContent = b.body.textContent.trim();
+ if (b.body.textContent === "") b.body.parentElement.remove();
+ b.body = null;
+ }
+ b.buf = "";
+ }
+
var es = new EventSource("/jobs/" + jobID + "/events");
es.onmessage = function(e) {
var ev = JSON.parse(e.data);
+
+ if (ev.type === "resync") {
+ // The subscription started with nothing to replay, and the
+ // hub is at seq ev.seq. If we last rendered something else,
+ // we missed events that are no longer replayable.
+ if (lastSeq !== 0 && (typeof ev.seq !== "number" || ev.seq !== lastSeq)) {
+ resyncPage();
+ }
+ return;
+ }
+
+ if (typeof ev.seq === "number") {
+ if (lastSeq === 0) {
+ lastSeq = ev.seq; // first event: fresh page, or joining a replay
+ } else if (ev.seq === lastSeq + 1) {
+ lastSeq = ev.seq; // contiguous: render
+ } else {
+ resyncPage(); // gap (dropped events) or duplicate replay
+ return;
+ }
+ }
+
var shouldScroll = nearBottom();
switch (ev.type) {
case "reasoning_start":
- reasoningBody = newBlock("reasoning", "Thinking");
+ blocks.reasoning.body = null;
+ blocks.reasoning.buf = "";
break;
case "reasoning_delta":
- if (reasoningBody) reasoningBody.textContent += ev.text;
+ onDelta("reasoning", ev.text);
break;
case "reasoning_end":
- // Model output routinely starts/ends with newlines; drop them
- // so the finished block matches the static (trimmed) view.
- if (reasoningBody) reasoningBody.textContent = reasoningBody.textContent.trim();
- reasoningBody = null;
+ onEnd("reasoning");
break;
case "content_start":
- contentBody = newBlock("content", null);
+ blocks.content.body = null;
+ blocks.content.buf = "";
break;
case "content_delta":
- if (contentBody) contentBody.textContent += ev.text;
+ onDelta("content", ev.text);
break;
case "content_end":
- if (contentBody) contentBody.textContent = contentBody.textContent.trim();
- contentBody = null;
+ onEnd("content");
break;
case "tool":
newToolBlock(ev);
break;
case "status":
- es.close();
- location.reload();
+ resyncPage();
return;
}
diff --git a/internal/web/web.go b/internal/web/web.go
index 55ab97f..1a850f9 100644
--- a/internal/web/web.go
+++ b/internal/web/web.go
@@ -302,7 +302,7 @@ func (s *Server) handleJobEvents(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Connection", "keep-alive")
w.WriteHeader(http.StatusOK)
- buffered, ch, cancel := s.hub.Subscribe(id)
+ buffered, seq, ch, cancel := s.hub.Subscribe(id)
defer cancel()
write := func(ev livelog.Event) bool {
@@ -320,6 +320,19 @@ func (s *Server) handleJobEvents(w http.ResponseWriter, r *http.Request) {
return true
}
+ // If there is nothing to replay, tell the client where the hub is
+ // at: if the hub is ahead of the client's last rendered event, the
+ // client missed events that are no longer replayable and must fall
+ // back to the static page. If there is something to replay, no
+ // marker is needed β the replayed events' Seqs are the continuity
+ // check (the client renders them if contiguous with what it has
+ // and reloads otherwise).
+ if len(buffered) == 0 {
+ if !write(livelog.Event{Type: livelog.Resync, Seq: seq}) {
+ return
+ }
+ }
+
for _, ev := range buffered {
if !write(ev) {
return
diff --git a/internal/web/web_test.go b/internal/web/web_test.go
index ded09b2..7e60664 100644
--- a/internal/web/web_test.go
+++ b/internal/web/web_test.go
@@ -104,6 +104,92 @@ func TestJobsAndDetail(t *testing.T) {
}
}
+// TestJobEventsSequenceNumbers verifies that the SSE stream numbers
+// every event (per job, monotonically) and opens with a resync marker
+// carrying the hub's current seq when there is nothing to replay, so a
+// client can detect dropped events and fall back to the static page
+// (issue #60).
+func TestJobEventsSequenceNumbers(t *testing.T) {
+ s, st := testServer(t)
+ ctx := context.Background()
+
+ if err := st.CreateJob(ctx, store.Job{ID: "job-1", EventKind: "issue:new", Agent: "leon", Owner: "acme", Repo: "widgets", IssueIndex: 1}); err != nil {
+ t.Fatal(err)
+ }
+
+ // Nothing buffered: the stream must open with a resync marker
+ // carrying the hub's current seq (0 for a fresh job, so omitted).
+ evCtx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
+ defer cancel()
+
+ rr := httptest.NewRecorder()
+ s.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/jobs/job-1/events", nil).WithContext(evCtx))
+ if rr.Code != http.StatusOK {
+ t.Fatalf("expected 200, got %d: %s", rr.Code, rr.Body.String())
+ }
+ if !strings.HasPrefix(rr.Body.String(), `data: {"type":"resync"}`) {
+ t.Fatalf("expected stream to open with a resync marker, got: %s", rr.Body.String())
+ }
+
+ // After a block is published, a new subscriber gets the buffered
+ // events numbered contiguously from 1, with no resync marker: the
+ // replayed seqs are the continuity check.
+ s.hub.Publish("job-1", livelog.Event{Type: livelog.ContentStart})
+ s.hub.Publish("job-1", livelog.Event{Type: livelog.ContentDelta, Text: "hi"})
+
+ evCtx2, cancel2 := context.WithTimeout(context.Background(), 100*time.Millisecond)
+ defer cancel2()
+
+ rr = httptest.NewRecorder()
+ s.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/jobs/job-1/events", nil).WithContext(evCtx2))
+ body := rr.Body.String()
+
+ if !strings.Contains(body, `{"type":"content_start","seq":1}`) ||
+ !strings.Contains(body, `{"type":"content_delta","seq":2,"text":"hi"}`) {
+ t.Fatalf("expected buffered events numbered 1 and 2, got: %s", body)
+ }
+ if strings.Contains(body, "resync") {
+ t.Fatalf("did not expect a resync marker with a non-empty buffer, got: %s", body)
+ }
+}
+
+// TestJobDetailLiveScript verifies the live view's script creates
+// reasoning/content blocks lazily (on the first non-whitespace delta,
+// not on the *_start event) and enforces event-sequence continuity, so
+// a whitespace-only turn leaves no empty block shell and dropped
+// events trigger a fallback to the static page (issue #60).
+func TestJobDetailLiveScript(t *testing.T) {
+ s, st := testServer(t)
+ ctx := context.Background()
+
+ if err := st.CreateJob(ctx, store.Job{ID: "job-1", EventKind: "issue:new", Agent: "leon", Owner: "acme", Repo: "widgets", IssueIndex: 1}); err != nil {
+ t.Fatal(err)
+ }
+ if err := st.MarkJobStarted(ctx, "job-1"); err != nil {
+ t.Fatal(err)
+ }
+
+ rr := httptest.NewRecorder()
+ s.Handler().ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/jobs/job-1", nil))
+ if rr.Code != http.StatusOK {
+ t.Fatalf("expected 200, got %d: %s", rr.Code, rr.Body.String())
+ }
+
+ body := rr.Body.String()
+
+ for _, want := range []string{
+ `var lastSeq = 0;`,
+ `if (ev.type === "resync")`,
+ `ev.seq === lastSeq + 1`,
+ `if (b.buf.trim() === "") return;`,
+ `if (b.body.textContent === "") b.body.parentElement.remove();`,
+ } {
+ if !strings.Contains(body, want) {
+ t.Fatalf("expected live script to contain %q", want)
+ }
+ }
+}
+
// TestJobDetailTrimsBlockWhitespace verifies that reasoning/content
// blocks are rendered without the leading/trailing newlines the model
// routinely emits: the block body uses white-space: pre-wrap, so those
Thinking
The diff looks clean. A few final things to confirm:
1. **`TestJobDetailLiveScript`** asserts `if (b.buf.trim() === "") return;` β but the actual line in the template is `if (b.buf.trim() === "") return; // whitespace so far: no block yet`. Since the test passed, the substring match is working. β
2. One point to double-check: in `onDelta`, when a block is lazily created, `b.body.textContent = b.buf` β b.buf may contain leading whitespace (e.g., "\n\nHello"). This matches the legacy behavior (the block displays the raw leading whitespace during streaming, and it gets trimmed on end). β
3. **Edge case: `resyncPage()` is called, and then `return`** β in the seq check branch, we `return` after `resyncPage()`. In the resync branch, we `return` unconditionally. β
4. **`status` case**: `resyncPage(); return;` β same as before. β
5. What about the `shouldScroll` variable β it's computed after the seq check, so no scroll happens on resync/reload. β
6. **Go template**: `{{.Job.ID}}` β jobID is a uuid string. β
7. **JSON `seq,omitempty`** β for a resync with seq=0, the JSON is `{"type":"resync"}`. The client handles the missing seq: `typeof ev.seq !== "number"` β if lastSeq !== 0, treat as out of sync. β
One more consideration β **the `Event` struct field alignment**: I changed `Type Type` and added `Seq uint64` β gofmt should align the tags. Let me run gofmt to confirm the formatting is correct.
Also, let me double-check that `go vet` passed (it did). I'll run gofmt -l to check for formatting issues.
The diff is clean. Let me verify gofmt compliance and run the full suite one final time:
Tool
π§ bash
{"command": "cd /project && gofmt -l . && echo \"---gofmt clean---\" && go build ./... && go test ./... 2>&1 | tail -12"}
Arguments
{"command": "cd /project && gofmt -l . && echo \"---gofmt clean---\" && go build ./... && go test ./... 2>&1 | tail -12"}
Result
---gofmt clean---
? github.com/abrander/zoo/cmd/zoo [no test files]
ok github.com/abrander/zoo/internal/agentrun (cached)
ok github.com/abrander/zoo/internal/config (cached)
ok github.com/abrander/zoo/internal/forgejo (cached)
ok github.com/abrander/zoo/internal/livelog (cached)
ok github.com/abrander/zoo/internal/llm (cached)
ok github.com/abrander/zoo/internal/scheduler (cached)
ok github.com/abrander/zoo/internal/store (cached)
ok github.com/abrander/zoo/internal/tools (cached)
ok github.com/abrander/zoo/internal/web (cached)
Thinking
Everything is clean and green. Let's commit and push.
Wait β before committing, let me reconsider one more potential issue: the `TestJobsAndDetail` test in web_test.go has a section that publishes a ContentDelta and expects the body to contain "streaming". With my changes, the SSE stream now first writes a resync marker (buffer is empty at subscribe time... no wait β the publish happens before the request, so at subscribe time the buffer is not empty β no resync, just the delta event with seq. Body = `data: {"type":"content_delta","seq":1,"text":"streaming"}\n\n`. Contains "streaming" β (test passed).
Another check β the `handleJobEvents` for a non-live job returns before subscribing (no resync). β (TestJobsAndDetail checks for an empty body for job-2 β).
Now, one more scenario I want to think through: **multiple simultaneous subscribers** (two browser tabs). Each has its own channel; seq is shared. Both receive the same seq. β Independent lastSeq per tab. β
And **a new tab opened mid-run**: static page (checkpointed blocks) + SSE: buffer replay (current block) with seq; client's lastSeq=0 β accepts the first replayed seq; contiguous β renders. β
**A new tab opened exactly at a checkpoint boundary**: buffer is empty β resync (seq=S). Client's lastSeq=0 β no-op. Next event (S+1) β accepted (lastSeq=0). β
I'm confident in this design. Let's commit and push, then open a PR.
Commit message:
```
Fix empty block bodies in the live job log view
The live (SSE) view could render a .block-body with no text in it,
while the static view (and the stored log) had the text β or the block
was missing entirely. Two causes:
1. Whitespace-only model output. The live JS created a block on
content_start/reasoning_start and trimmed it on *_end; when the
model's message was whitespace-only (e.g. "\n", common on
tool-call turns), an empty shell was left in the DOM. The static
view drops such blocks (buildBlocks), so the shell vanished on
reload.
2. Dropped SSE events. The hub deliberately drops events for slow
subscribers (full channel), and the client's start/delta/end state
machine could not recover from a gap: dropped deltas left empty or
truncated blocks, a dropped *_end left an untrimmed (over-padded)
block and orphaned it on the next turn.
Fix:
- Create reasoning/content blocks lazily, on the first non-whitespace
delta, and drop the block on *_end if nothing is left β the live
view now matches the static view for whitespace-only turns.
- Number every hub event with a per-job monotonically increasing Seq;
when a subscription starts with an empty replay buffer, the SSE
handler sends a "resync" marker with the hub's current seq. The
client enforces sequence continuity and falls back to the static
page (always complete) on any gap or duplicate replay.
Fixes #60
```
Let's commit, push, and open a PR.
Everything is green. Let me commit and push:
Tool
π§ bash
{"command": "cd /project && git add -A && git commit -m \"Fix empty block bodies in the live job log view\n\nThe live (SSE) view could render a .block-body with no text in it,\nwhile the stored log had the text β or the block was missing entirely.\nTwo causes:\n\n1. Whitespace-only model output. The live JS created a block on\n content_start/reasoning_start and trimmed it on *_end; when the\n model's message was whitespace-only (e.g. a bare newline, common on\n tool-call turns), an empty shell was left in the DOM. The static\n view drops such blocks (buildBlocks), so the shell vanished on\n reload.\n\n2. Dropped SSE events. The hub deliberately drops events for slow\n subscribers (full channel), and the client's start/delta/end state\n machine could not recover from a gap: dropped deltas left empty or\n truncated blocks, and a dropped *_end left an untrimmed (over-\n padded) block that the next turn then orphaned.\n\nFix:\n- Create reasoning/content blocks lazily, on the first non-whitespace\n delta, and drop the block on *_end if nothing is left β the live\n view now matches the static view for whitespace-only turns.\n- Number every hub event with a per-job monotonically increasing Seq;\n when a subscription starts with an empty replay buffer, the SSE\n handler sends a \\\"resync\\\" marker with the hub's current seq. The\n client enforces sequence continuity and falls back to the static\n page (which is always complete) on any gap or duplicate replay.\n\nFixes #60\" && git push origin issue-60-greg 2>&1 | tail -3"}
Arguments
{"command": "cd /project && git add -A && git commit -m \"Fix empty block bodies in the live job log view\n\nThe live (SSE) view could render a .block-body with no text in it,\nwhile the stored log had the text β or the block was missing entirely.\nTwo causes:\n\n1. Whitespace-only model output. The live JS created a block on\n content_start/reasoning_start and trimmed it on *_end; when the\n model's message was whitespace-only (e.g. a bare newline, common on\n tool-call turns), an empty shell was left in the DOM. The static\n view drops such blocks (buildBlocks), so the shell vanished on\n reload.\n\n2. Dropped SSE events. The hub deliberately drops events for slow\n subscribers (full channel), and the client's start/delta/end state\n machine could not recover from a gap: dropped deltas left empty or\n truncated blocks, and a dropped *_end left an untrimmed (over-\n padded) block that the next turn then orphaned.\n\nFix:\n- Create reasoning/content blocks lazily, on the first non-whitespace\n delta, and drop the block on *_end if nothing is left β the live\n view now matches the static view for whitespace-only turns.\n- Number every hub event with a per-job monotonically increasing Seq;\n when a subscription starts with an empty replay buffer, the SSE\n handler sends a \\\"resync\\\" marker with the hub's current seq. The\n client enforces sequence continuity and falls back to the static\n page (which is always complete) on any gap or duplicate replay.\n\nFixes #60\" && git push origin issue-60-greg 2>&1 | tail -3"}
Result
[issue-60-greg e24ca15] Fix empty block bodies in the live job log view
5 files changed, 283 insertions(+), 29 deletions(-)
To https://code.stdio.dk/abrander/zoo.git
* [new branch] issue-60-greg -> issue-60-greg
Thinking
Push complete. Next, I'll open a pull request to main.
Now let me open the pull request:
Tool
π§ open_pull_request
{"base": "main", "body": "## What was wrong\n\nThe empty `block-body` divs are a **live (SSE) view** artifact β the static view (old logs) can't produce them: `buildBlocks` trims block text and drops whitespace-only blocks entirely, and the static template always renders `block-body` inline with its (non-empty) text. The issue's empty example is also unindented JS-created DOM, not the static template.\n\nTwo root causes:\n\n1. **Whitespace-only model output β empty block shell.** The live JS created a block on `content_start`/`reasoning_start` and trimmed the accumulated text on `*_end`. When the model emits a message whose content is only whitespace (e.g. a bare `\"\\n\"` β common on tool-call turns), the block was left as an empty shell in the DOM. The static view drops such blocks, so the shell vanished on reload β which is why it looked like \"maybe just when streaming\".\n2. **Dropped SSE events desync the live view.** `livelog.Hub` deliberately drops events for slow subscribers (full 256-slot channel β background tab, network stall). The client's start/delta/end state machine can't recover from a gap: dropped deltas β empty or truncated block (\"there should be some text in there\"); dropped `*_end` β untrimmed block with excess vertical space (the issue's second example) that the next turn then orphans.\n\n## The fix\n\n- **Lazy block creation** (`internal/web/templates.go`): reasoning/content blocks are now created on the first *non-whitespace* delta instead of on the `*_start` event, and dropped on `*_end` if nothing is left. A whitespace-only turn no longer produces an empty shell at all, and the live view matches the static view.\n- **Event sequence numbers** (`internal/livelog/hub.go`, `internal/web/web.go`): every published event gets a per-job monotonically increasing `Seq`. When a subscription starts with an empty replay buffer, the SSE handler sends a `resync` marker carrying the hub's current seq. The client enforces strict sequence continuity and falls back to the static page β which is always complete β on any gap or duplicate replay, instead of rendering a desynced block.\n\n## Tests\n\n- `livelog`: seqs are monotonic and per-job; `Subscribe` returns the current seq atomically with the buffer snapshot.\n- `web`: the SSE stream opens with a `resync` marker when there's nothing to replay, and buffered events are numbered contiguously; the live script contains the lazy-creation and continuity logic.\n- The client state machine was additionally verified against 12 scenarios (whitespace-only turns, gaps, reconnects with/without replay, duplicate replays, consecutive turns, tool events, status) via a simulation of the rendered JS β all pass.\n\n`go build`, `go vet`, and the full test suite are green.\n\nFixes #60", "head": "issue-60-greg", "title": "Fix empty block bodies in the live job log view"}
Arguments
{"base": "main", "body": "## What was wrong\n\nThe empty `block-body` divs are a **live (SSE) view** artifact β the static view (old logs) can't produce them: `buildBlocks` trims block text and drops whitespace-only blocks entirely, and the static template always renders `block-body` inline with its (non-empty) text. The issue's empty example is also unindented JS-created DOM, not the static template.\n\nTwo root causes:\n\n1. **Whitespace-only model output β empty block shell.** The live JS created a block on `content_start`/`reasoning_start` and trimmed the accumulated text on `*_end`. When the model emits a message whose content is only whitespace (e.g. a bare `\"\\n\"` β common on tool-call turns), the block was left as an empty shell in the DOM. The static view drops such blocks, so the shell vanished on reload β which is why it looked like \"maybe just when streaming\".\n2. **Dropped SSE events desync the live view.** `livelog.Hub` deliberately drops events for slow subscribers (full 256-slot channel β background tab, network stall). The client's start/delta/end state machine can't recover from a gap: dropped deltas β empty or truncated block (\"there should be some text in there\"); dropped `*_end` β untrimmed block with excess vertical space (the issue's second example) that the next turn then orphans.\n\n## The fix\n\n- **Lazy block creation** (`internal/web/templates.go`): reasoning/content blocks are now created on the first *non-whitespace* delta instead of on the `*_start` event, and dropped on `*_end` if nothing is left. A whitespace-only turn no longer produces an empty shell at all, and the live view matches the static view.\n- **Event sequence numbers** (`internal/livelog/hub.go`, `internal/web/web.go`): every published event gets a per-job monotonically increasing `Seq`. When a subscription starts with an empty replay buffer, the SSE handler sends a `resync` marker carrying the hub's current seq. The client enforces strict sequence continuity and falls back to the static page β which is always complete β on any gap or duplicate replay, instead of rendering a desynced block.\n\n## Tests\n\n- `livelog`: seqs are monotonic and per-job; `Subscribe` returns the current seq atomically with the buffer snapshot.\n- `web`: the SSE stream opens with a `resync` marker when there's nothing to replay, and buffered events are numbered contiguously; the live script contains the lazy-creation and continuity logic.\n- The client state machine was additionally verified against 12 scenarios (whitespace-only turns, gaps, reconnects with/without replay, duplicate replays, consecutive turns, tool events, status) via a simulation of the rendered JS β all pass.\n\n`go build`, `go vet`, and the full test suite are green.\n\nFixes #60", "head": "issue-60-greg", "title": "Fix empty block bodies in the live job log view"}
Result
Pull request opened
Thinking
The PR has been opened. Next, I'll leave a comment on the issue summarizing what I did.
Now let me leave a comment on the issue summarizing the investigation and fix:
Tool
π§ comment
{"body": "Investigated β the empty `block-body` divs are a **live (streaming) view** artifact, not a problem with the stored log. The static view (old logs) can't produce them: `buildBlocks` trims block text and drops whitespace-only blocks entirely, and the static template always renders the body inline with its (non-empty) text. Your empty example is also unindented JS-created DOM, not the static template β consistent with \"maybe just when streaming\".\n\n**Two root causes:**\n\n1. **Whitespace-only model output β empty block shell.** The live JS created a block on `content_start`/`reasoning_start` and trimmed the accumulated text on `*_end`. When the model emits a message whose content is only whitespace (e.g. a bare `\"\\n\"` β common on tool-call turns), the block was left as an empty shell in the DOM. The static view drops such blocks, so the shell vanished on reload.\n2. **Dropped SSE events desync the live view.** The `livelog` hub deliberately drops events for slow subscribers (full 256-event channel β background tab, network stall). The client's start/delta/end state machine can't recover from a gap: dropped deltas β empty or truncated block (\"there should be some text in there\"); a dropped `*_end` β untrimmed block with excess vertical space (your second example) that the next turn then orphans.\n\n**The fix (PR opened):**\n\n- Reasoning/content blocks are now created **lazily, on the first non-whitespace delta**, and dropped on `*_end` if nothing is left β a whitespace-only turn no longer produces an empty shell at all, and the live view matches the static view.\n- Every hub event now carries a **per-job sequence number**; when a subscription starts with an empty replay buffer the server sends a `resync` marker with the hub's current seq. The client enforces strict sequence continuity and **falls back to the static page (always complete) on any gap or duplicate replay**, instead of rendering a desynced block.\n\nTests added for the seq/resync contract and the live script; the client state machine was also verified against 12 scenarios (whitespace-only turns, gaps, reconnects with/without replay, consecutive turns, tool events, status). Full suite green."}
Arguments
{"body": "Investigated β the empty `block-body` divs are a **live (streaming) view** artifact, not a problem with the stored log. The static view (old logs) can't produce them: `buildBlocks` trims block text and drops whitespace-only blocks entirely, and the static template always renders the body inline with its (non-empty) text. Your empty example is also unindented JS-created DOM, not the static template β consistent with \"maybe just when streaming\".\n\n**Two root causes:**\n\n1. **Whitespace-only model output β empty block shell.** The live JS created a block on `content_start`/`reasoning_start` and trimmed the accumulated text on `*_end`. When the model emits a message whose content is only whitespace (e.g. a bare `\"\\n\"` β common on tool-call turns), the block was left as an empty shell in the DOM. The static view drops such blocks, so the shell vanished on reload.\n2. **Dropped SSE events desync the live view.** The `livelog` hub deliberately drops events for slow subscribers (full 256-event channel β background tab, network stall). The client's start/delta/end state machine can't recover from a gap: dropped deltas β empty or truncated block (\"there should be some text in there\"); a dropped `*_end` β untrimmed block with excess vertical space (your second example) that the next turn then orphans.\n\n**The fix (PR opened):**\n\n- Reasoning/content blocks are now created **lazily, on the first non-whitespace delta**, and dropped on `*_end` if nothing is left β a whitespace-only turn no longer produces an empty shell at all, and the live view matches the static view.\n- Every hub event now carries a **per-job sequence number**; when a subscription starts with an empty replay buffer the server sends a `resync` marker with the hub's current seq. The client enforces strict sequence continuity and **falls back to the static page (always complete) on any gap or duplicate replay**, instead of rendering a desynced block.\n\nTests added for the seq/resync contract and the live script; the client state machine was also verified against 12 scenarios (whitespace-only turns, gaps, reconnects with/without replay, consecutive turns, tool events, status). Full suite green."}
Result
Comment posted
Thinking
Done. Let me do a final check to make sure everything is in place:
1. β
Investigated the issue and identified two root causes
2. β
Implemented the fix (lazy block creation + seq/resync gap detection)
3. β
Added tests (hub seq test, web SSE contract test, live script test)
4. β
All tests passing, gofmt clean, go vet clean
5. β
Committed and pushed to issue-60-greg
6. β
Opened a PR
7. β
Commented on the issue
Let me do a final check to make sure the branch state is clean.
Tool
π§ bash
{"command": "cd /project && git status && git log --oneline -2"}
Arguments
{"command": "cd /project && git status && git log --oneline -2"}
Result
On branch issue-60-greg
nothing to commit, working tree clean
e24ca15 Fix empty block bodies in the live job log view
98298f6 Merge pull request 'Fix excessive vertical space in job view blocks (#53)' (#55) from issue-53-greg into main
Thinking
Everything is complete:
1. **Investigation**: Identified the two root causes of the empty `block-body` div:
- Whitespace-only model output β empty block shells in the live JS view
- Dropped SSE events desynchronizing the client's block state machine
2. **Fixes**:
- Lazy block creation in the live JS (create only on the first non-whitespace delta, and remove if empty on end)
- Per-job event sequence numbers + resync markers + strict continuity check with fallback to the static page
3. **Tests**: Added hub seq tests, web SSE contract tests, and live script tests. Simulated 12 client scenarios β all passing.
4. **Deliverables**: Committed, pushed, opened a PR, and commented on the issue.
Working tree is clean, and the branch has been pushed. Done.
Done. Summary of the work on issue #60 ("Empty block-body"):
**Diagnosis** β the empty `block-body` divs are a **live (SSE) view** artifact, not a stored-log problem (the static view trims text and drops whitespace-only blocks, and the issue's empty example is unindented JS-created DOM). Two root causes:
1. **Whitespace-only model output** (e.g. a bare `"\n"` on tool-call turns): the live JS created a block on `content_start`, trimmed to `""` on `content_end` β empty shell left in the DOM (vanishes on reload, since the static view drops such blocks).
2. **Dropped SSE events**: the `livelog` hub deliberately drops events for slow subscribers (full 256-slot channel), and the client's start/delta/end state machine couldn't recover β dropped deltas β empty/truncated blocks ("there should be some text in there"); dropped `*_end` β untrimmed, over-padded blocks (the issue's second example).
**Fix** (branch `issue-60-greg`, PR opened):
- `internal/web/templates.go` β reasoning/content blocks are created **lazily on the first non-whitespace delta** and dropped on `*_end` if empty, so the live view matches the static view; the client also enforces **event-sequence continuity** and falls back to the static page (always complete) on any gap or duplicate replay.
- `internal/livelog/hub.go` β every published event gets a per-job monotonically increasing `Seq`; `Subscribe` returns the current seq atomically with the buffer snapshot; new `Resync` event type.
- `internal/web/web.go` β the SSE handler sends a `resync` marker (with the hub's current seq) when a subscription starts with an empty replay buffer, so a reconnecting client can detect it fell behind even when nothing is replayable.
**Verification** β new tests for the seq/resync contract and live script; the client state machine additionally verified against 12 simulated scenarios (whitespace-only turns, gaps, reconnects with/without replay, duplicate replays, consecutive turns, tool events, status). `go build`, `go vet`, `gofmt`, and the full test suite are green.