gramps
e37215d9c4
TASK 32·4. A plain MP4 keeps its index (moov) at the end, so a power cut or a killed process left the entire recording unreadable even though every video byte was on disk. The record block now carries `-movflags +frag_keyframe+empty_moov+default_base_moof`: index first, a playable fragment flushed at every keyframe, so an interrupted take plays to the last fragment. Record block only — the FLV stream output has no index and never gets the flags. Rename-on-stop is untouched. Test: `Args_RecordBlock_IsFragmentedMp4_SoACrashKeepsTheFile` asserts the flags on the record block and their absence from the streaming block. Not yet proven on a real interrupted take (kill ffmpeg mid-recording, play the result); the args test is by construction. Docs: task-32 slice 4 ticked with that caveat, TASKS row, output.md record note, HANDOFF. verify.sh: 550 passed (mouse-injection test excluded, desktop in use), 0 warnings.
3.5 KiB
3.5 KiB
TASK 32 — Stream resilience (queued 2026-09-01 — merges the orphaned TASK 2 resume clause into the pills/signs architecture)
Catalog:
TASKS.md— status and requirements live here.
Goal: a dropped stream heals itself when physically possible, tells the truth when it isn't, and gets the creator back on air in one click. The ON-AIR sign + primary button in the top bar are the surface — they already mean "reality" (pills = intent, lights = reality, TASK 18/30); reality just isn't two-state. Resumption of a completed broadcast is explicitly out of scope (impossible via the API — creator ruling 2026-09-01): no lying in the copy.
Slices (one integration test each, in order):
- ☐ Blip retry — app-side encoder restart: push dies while live (ProcessFailed / stdin backpressure death) → bounded-backoff relaunch (2s/5s/10s, N attempts) against the cached constant reusable-stream ingest URL. Success = push running again while the broadcast is still live; viewers never know. Fixes the map's stale "ffmpeg does reconnect" claim (corrected 2026-09-01: reconnect flags are input-side only). Test: fake process fails once then starts → pump recovers without surfacing to the VM.
- ☐ Measured grace + the sign — while the push is dead, escalate the existing health poll
(30s → ~5s). ON-AIR dot goes amber "RECONNECTING" with a mm:ss countdown to the observed
YouTube cutoff; the grace length is a measured, pinned constant — probe it on a real private
test stream, cite the observation (spin-guard rule; do NOT invent a number). Poll reports the
broadcast
complete→ dot red "OFF AIR", primary button relabels "● Back on air" and pulses. Test: fake status provider drives the dot through live → reconnecting → cut-off. - ☐ One-click Back on air — the relabeled button fires the existing go-live path with saved
Broadcast.*+ cached stream, dialog skipped: new broadcast, new VOD (accepted cost, stated in-product). Test: seeded saved form + fake stream service → click creates + pushes, no dialog. - ✅ Crash-safe recording (shipped 2026-11-05) — fragmented MP4 on the record block (
-movflags frag_keyframe+empty_moov+default_base_moof): plain MP4's trailing moov atom means a power loss kills the WHOLE file. Rename-on-stop unchanged. Closes the TASK 18 "MKV as an option" design-note remnant (fragmented MP4 chosen over MKV: single container, YouTube-upload-native — verify player/ editor tolerance, cite the research). Test:Args_RecordBlock_IsFragmentedMp4_SoACrashKeepsTheFile— the flags are on the record block and absent from the streaming block. Verified by construction only: the file still needs one real interrupted-take check on Windows (kill ffmpeg mid-recording, play the result). - ☐ Pre-flight — before broadcast insert, one TCP probe to the ingest host:1935 (~2s timeout). Unreachable → Error toast, no insert, no ghost broadcast ("check VPN/network"). The "forgot the VPN" story, solved as prevention instead of recovery. Test: fake probe failure aborts go-live before any API call.
Design decisions
- The sign is the status, the button is the action — no new chrome, no log lines, no spinners.
- Honest windows: countdown = observed grace; at zero we say OFF AIR, we don't pretend to reconnect.
- Why us > incumbents: constant reusable stream + persisted form make retry/restart cheap; OBS shows a reconnecting log line and Streamlabs silently dies.