- PortMessageType union grows 4 → 7 entries adding the D-P2-01 Blob URL
migration triplet (CREATE_DOWNLOAD_URL, DOWNLOAD_URL, REVOKE_DOWNLOAD_URL).
- PortMessage interface gains optional dataBase64, mimeType, url fields
following the same optional-tagged-union pattern as the existing
segments? field. Wire format reuses the D-12 base64 precedent from
src/shared/binary.ts (chrome.runtime.Port JSON-serializes payloads).
- Docstring above the union explains the SW↔offscreen mint/revoke
lifecycle and points to .planning/phases/02-stabilize-export-pipeline/
02-CONTEXT.md D-P2-01 for the full architectural rationale.
- No SessionMetadata changes — meta.urls migration is Plan 02-03 territory.
Pure type-extension step for the Option C architectural refactor of the
offscreen↔SW port lifecycle (.planning/debug/empty-archive-port-race.md).
PortMessage.requestId is optional so PING/PONG keep their no-payload
shape. REQUEST_BUFFER and BUFFER will populate it once the recorder
(offscreen) and getVideoBufferFromOffscreen (SW) are wired up in the
next commits. The narrowing remains structural — every consumer must
still validate `type` before accessing `requestId`.
PONG joins PING as a no-payload liveness signal. The SW echoes PONG on
PING, closing the health-probe loop the offscreen uses to detect a dead
port (replacing the 290 s pre-emptive setTimeout that was the proximate
cause of the H1 race window per the bisect).
No runtime change. 52 tests, 10 RED still RED (waiting for impl).
tsc --noEmit exit 0; type-safety grep clean.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Pure rename pass — zero behavioural change at any call site. The
prior "chunk" naming is a vestige of D-09..D-11's chunk-level
buffer; under D-13 the unit of transfer is a self-contained ~10 s
WebM segment, so the type name now matches the data shape.
Renames propagated atomically:
- src/shared/types.ts
* TransferredVideoChunk → TransferredVideoSegment
(also: the `isFirst?: boolean` field is dropped — D-13 segments
are all implicitly their own header, so the flag is meaningless
and only existed for the retired ring-buffer's pin semantics)
* VideoChunk → VideoSegment (drops `isFirst?` for the same reason)
* PortMessage.chunks? → PortMessage.segments?
* VideoBufferResponse.chunks → VideoBufferResponse.segments
- src/offscreen/recorder.ts
* import type rename
* encodeAndSendBuffer's per-element accumulator + filter type
* the port.postMessage payload field
- src/background/index.ts
* import type rename
* getVideoBufferFromOffscreen reads `(msg as {segments?}).segments`
(matching the new wire field name)
* empty-buffer returns `{ segments: [] }`
* mergeVideoSegments signature takes VideoSegment[]
* createArchive consumes videoBufferResponse.segments
* saveArchive log line says "segments"
Verification:
- npx tsc --noEmit clean.
- npx vitest run → 28 passed / 2 failed (the 2 fixture-empirical
ffmpeg dry-runs; unchanged — they're gated on ./smoke.sh regen).
- npm run build succeeds, all 60 modules transformed.
- grep predicates clean in src/:
* no addChunk / trimAged / firstChunkSaved / isFirst
* no TransferredVideoChunk / VideoChunk (old names)
* 21 occurrences of new names propagated correctly
- Pre-existing port-serialization.test.ts still GREEN: its `isFirst`
references are inside inline-test-scoped objects (not imports
from production types), and its tests assert JSON-roundtrip
behaviour rather than the production type shape.
- Add TransferredVideoChunk { data: string (base64); type: string
(MIME); timestamp: number; isFirst?: boolean } as the
JSON-serializable shape for chunks traversing the offscreen↔SW
chrome.runtime.Port boundary.
- Retarget PortMessage.chunks?: TransferredVideoChunk[] (was
VideoChunk[]). The in-memory VideoChunk type is unchanged — both
the offscreen ring buffer and the SW-side merge step keep using
it after decoding the wire payload.
- No behavior change yet; this commit only lands the type. The
encode/decode call sites land in the next two commits.
Refs: debug session d12-blob-port-transfer-fails.
- Add PortMessageType and PortMessage interface to src/shared/types.ts
for the long-lived port (offscreen ↔ SW; D-17 / Plan 04 wires the
ping loop + REQUEST_BUFFER / BUFFER traffic).
- Remove 'VIDEO_CHUNK' and 'VIDEO_CHUNK_SAVED' from MessageType union
(per D-19 — chunks no longer travel via chrome.runtime.sendMessage;
the IndexedDB SW-side plumbing is the audit P0 #2 broken path).
- OffscreenLogger class was already added alongside Task 2 because
recorder.ts imports it at module top.
Inline SW cleanup (Rule 3 — blocking dependency, plan acceptance gates
on `npx tsc --noEmit` exit 0):
- Remove src/background/index.ts VIDEO_CHUNK + VIDEO_CHUNK_SAVED case
branches (refs to deleted union members).
- Remove now-unreferenced loadChunkFromIndexedDB / openIndexedDB
(only reachable from the deleted VIDEO_CHUNK_SAVED branch).
- Remove now-unreferenced addVideoChunkFromBlob / cleanupVideoBuffer
/ firstChunkSaved / VIDEO_BUFFER_DURATION_MS constant (the SW-side
ring buffer now lives in src/offscreen/recorder.ts per D-16).
- Keep SW-side `videoBuffer: VideoChunk[] = []` as a placeholder; Plan
04 wires it to fetch from offscreen over the keepalive port. The
remaining `getVideoBuffer` + `saveArchive` callers continue to
compile against the empty array until Plan 04 lands.
- Plan 05 owns the broader SW shell cleanup.
Verification (post-commit):
- npx vitest run tests/offscreen/ring-buffer.test.ts tests/offscreen/codec-check.test.ts → 6/6 PASS
- npx tsc --noEmit → exit 0
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
