224 lines
15 KiB
Markdown
224 lines
15 KiB
Markdown
# ytplayer — project facts for agents
|
||
|
||
## What this is
|
||
Ad-free YouTube player. Three shells share `frontend/`: **web PWA** (Bun + Hono in
|
||
`server/`, the production deployment), Tauri (Windows), zero-native (Linux/macOS).
|
||
The PWA is what runs in production; `legacy/` holds the old native-only docs.
|
||
|
||
## Repo map
|
||
|
||
| Path | What lives there |
|
||
|------|------------------|
|
||
| `frontend/app.js` | The entire UI (~3.6k lines, no framework): player, playlists, search, settings, sync |
|
||
| `frontend/sw.js` + `frontend/sw-update.js` | Service worker + update flow (FRAGILE — see below) |
|
||
| `frontend/opfs.js` / `opfs-worker.js` | OPFS offline audio cache |
|
||
| `frontend/fingerprint.js` | Browser fingerprint used as the sync key |
|
||
| `frontend/async-guard.js` | Stale-async-response guard (unit-tested) |
|
||
| `server/server.js` | Bun + Hono backend — endpoint list is in its header comment |
|
||
| `server/db.js` | libsql schema/queries (`users`, `profiles`, `video_history`, `media_cache`…) |
|
||
| `server/media-cache.js` | Server-side video cache: background fetch jobs, validation gate, x264 lane, LRU |
|
||
| `bin/yt-dlp` | Downloaded by `npm run setup`, gitignored |
|
||
| `scripts/` | icon generation, yt-dlp setup, push helper |
|
||
| `tests/` | Playwright e2e specs · unit tests live next to sources in `frontend/*.test.js` |
|
||
| `legacy/` | Old native-shell docs — do not treat as current |
|
||
|
||
API endpoints: `GET /api/search|channel|streams|download/:id|version|user/data|profile/load`,
|
||
`GET /api/media/:id|media/:id/status|media/stats`, `POST /api/media/:id/redownload`,
|
||
`POST /api/user/sync|profile/create|profile/save`, `GET /sw.js` (BUILD_TAG-injected), `GET /*` static.
|
||
JSON shapes mirror the Tauri Rust bridge exactly — don't change one side alone
|
||
(`/api/streams`' `data.serverCached` is additive and web-only).
|
||
|
||
## Server media cache (`server/media-cache.js`)
|
||
- Every played (`/api/streams`, LOW priority, ≤ `MEDIA_AUTO_MAX_SECONDS`) or saved
|
||
(`/api/download`, HIGH, ≤ 3 h) video gets ONE copy: `$MEDIA_DIR/<id>.<gen>.mp4`
|
||
(≤720p H.264 8-bit + AAC, faststart) + `<id>.<gen>.m4a` audio sidecar for audio-only
|
||
mode. `MEDIA_DIR` defaults to `./data/media` (the `ytplayer-data` volume in prod).
|
||
- Jobs are server-owned — **never pass a request AbortSignal into them**; a client
|
||
closing its tab must not kill a fetch. Downloads still run inside `withSaveSlot`.
|
||
- **Validation gate** (`validateMedia`): h264 yuv420p + AAC, container/stream durations
|
||
cover the source, a full `-c copy` demux pass with zero stderr, head + tail decode.
|
||
The demux pass is what catches a faststart file whose index is intact but whose
|
||
data is cut. Nothing reaches the cache dir without passing it; failures back off
|
||
(15 min · 2^n, max 24 h) and saves fall back to the legacy per-request path.
|
||
- `gen` is in the filename and URL (`/api/media/<id>?g=<gen>`): a URL never serves
|
||
different bytes. A replaced gen is kept 30 min so in-flight Range playback survives.
|
||
- **Compression lane** (rev `OPT_REV` = 2): niced x265 8-bit `-preset medium -crf 28`,
|
||
`hvc1` tag, anime-style tuning (`X265_TUNING`), `-fpsmax 30`, audio copied — kept only
|
||
if ≥15% smaller, and the copy's `vcodec` becomes `hevc`. **Sample-first**: videos ≥60 s
|
||
get two 10-s windows encoded first and compared with the source's own packet bytes
|
||
over the same timestamps; the full encode only runs if the prediction clears the 15%
|
||
bar (a skip costs ~20 s of video; a full encode ~2× realtime on the homelab).
|
||
**Why:** re-encoding YouTube's already-compressed H.264 usually needs MORE bits for
|
||
LOWER quality (generation loss) — on prod 0 of 5 videos shrank at CRF 28, one grew 25%
|
||
(VMAF 93.6 at 126% of source; capping to 60–70% drops VMAF to ~84–87). Only videos
|
||
where YouTube over-spent bits win (a live worship video: −34%). AnimeOut-style sizes
|
||
come from pristine Blu-ray sources, which YouTube never gives us. Bumping `OPT_REV`
|
||
re-queues every cached copy once at boot.
|
||
- **HEVC gating**: an HEVC copy is served only to clients that send `?hevc=1` on
|
||
`/api/streams` and `/api/download` (app.js `hevcCapable()` = canPlayType hvc1, minus a
|
||
per-device `ytpNoHevc` flag set when an HEVC copy fails to play). Everyone else gets
|
||
the pre-cache behaviour (YouTube proxy / legacy H.264 save). Verified: iPhone XR, Galaxy
|
||
S10, Windows Chrome play HEVC; AV1 fails on the XR (no decoder), so it isn't used.
|
||
The validation gate requires `hvc1` (Safari refuses `hev1`) and 8-bit 4:2:0.
|
||
- **Budget**: `MEDIA_CACHE_MAX_BYTES` (10 GiB) LRU by `last_access` (anything played in
|
||
the last 10 min is protected) + `MEDIA_MIN_FREE_BYTES` (5 GiB) disk guard → skip, stream.
|
||
- **Broken**: `POST /api/media/:id/redownload` (now-playing ⚠ Broken button). When a
|
||
client falls back from a cached copy (`/api/streams?nocache=1`) the server also
|
||
re-validates its copy and refetches it if it fails — never trusts one device's error.
|
||
- Ops: `curl https://worship.hesed.sbs/api/media/stats`; files under
|
||
`/app/data/media` in the container.
|
||
|
||
## Local dev
|
||
|
||
```bash
|
||
npm run setup # download bin/yt-dlp (once)
|
||
cd server && bun install
|
||
ln -s ../frontend public # once — the server serves ONLY ./public (Docker copies frontend/ there)
|
||
bun --hot server.js # http://localhost:3000
|
||
node --test frontend/ # unit tests (run from repo root)
|
||
npx playwright test # e2e (see Testing below)
|
||
```
|
||
|
||
Local DB file: `server/data/ytplayer.db` (gitignored). `BUILD_TAG` is computed from `./public` contents.
|
||
|
||
## Production deployment (web PWA)
|
||
- URL: **https://worship.hesed.sbs** (Traefik label in `docker-compose.yml`)
|
||
- Runs on the **homelab** Dokploy remote node; control plane is Dokploy on the VPS
|
||
(`193.160.119.172`, API key in `~/development/.secrets/dokploy-api.env`).
|
||
- Compose ID: **`wprYCM8T51f7JtSHb983p`** (project `ytplayer`, env `production`).
|
||
- **Pushing to git does NOT deploy.** Trigger explicitly (build ≈ 5–6 min):
|
||
```bash
|
||
ssh -i ~/.ssh/tmp_vps/dokploy_session root@193.160.119.172 \
|
||
"curl -s -X POST -H 'x-api-key: $KEY' -H 'Content-Type: application/json' \
|
||
-d '{\"composeId\":\"wprYCM8T51f7JtSHb983p\"}' http://localhost:3000/api/compose.deploy"
|
||
# poll composeStatus via /api/compose.one?composeId=... until done|error
|
||
```
|
||
- Confirm the deploy landed: `curl https://worship.hesed.sbs/api/version` — the
|
||
`buildTag` (content hash of every file under `./public`) must change.
|
||
- Homelab node is NOT always reachable on LAN; SSH via the VPS hop:
|
||
`ssh root@193.160.119.172` → `ssh root@10.8.0.2` (WireGuard). Container name:
|
||
`ytplayer-main-1dihzn-ytplayer-1`. DB: libsql file `/app/data/ytplayer.db`
|
||
(query with `docker exec <c> bun -e '...' `using `@libsql/client`).
|
||
|
||
## Update-flow architecture (fragile — read before touching)
|
||
- `GET /sw.js` is served by the server with the real `BUILD_TAG` **injected by
|
||
regex** over the fallback expression in `frontend/sw.js`. Never switch back to
|
||
an exact-string replace: when the fallback literal was bumped (`v1.0.3`→`v1.0.4`)
|
||
the exact match silently failed, the SW version froze, and **no client ever
|
||
received another update** while `/api/version` kept announcing one — the
|
||
"Update available keeps showing" bug.
|
||
- `BUILD_TAG` hashes **every** file under `./public` recursively. Don't reduce it
|
||
to a file subset; a change to an unlisted shell file would stop busting caches.
|
||
- **The banner has ONE rule** (`maybeShowUpdateBanner` in app.js): show it only
|
||
when the build this page runs differs from `/api/version`. The server stamps
|
||
the running build into index.html (`<meta name="ytp-build">`, at request
|
||
time like sw.js's BUILD_TAG); the SW caches that index.html with the rest of the
|
||
shell, so the meta always describes the code in the tab. The poll, a waiting
|
||
worker and the SW_UPDATE_AVAILABLE broadcast are only *prompts to re-check*.
|
||
This loop was "fixed" three times by chasing individual triggers — don't add
|
||
a trigger that calls `showUpdateBanner()` directly.
|
||
- **Refresh UI** (`frontend/sw-update.js`): `refreshShellInPlace()` re-downloads
|
||
every file the shell caches hold — cache-busted (`?__ytpfresh=`) so even an
|
||
OLD worker's cache-first handler can't answer from its cache, 3 tries per file,
|
||
all-or-nothing — and writes them into every versioned shell cache; then it
|
||
activates a waiting worker (SKIP_WAITING) if any and reloads once. A failed
|
||
download shows an error toast and re-offers later; it never reloads into the
|
||
old shell. `checkUpdateOutcome()` verifies after the reload (sessionStorage,
|
||
max 3 attempts) instead of looping.
|
||
- **Why it kept looping on prod:** the VPS→homelab link is slow and drops
|
||
requests. The SW install (`cache.addAll`, all-or-nothing) failed, Refresh UI
|
||
reloaded into the old cached shell, and the partial `ytplayer-<tag>` cache
|
||
left by the failed install later made activate broadcast "update available"
|
||
to pages that were already current. sw.js now precaches with
|
||
`cache: 'reload'`, retries each file, and deletes its partial cache on failure.
|
||
- Reproduce with the throttling/stalling proxy approach: WebKit (Playwright on
|
||
the Windows side) or Chrome over CDP against a scratch copy of the server,
|
||
stalling every Nth shell request after "deploying" v2. A fast local link never
|
||
shows the bug.
|
||
|
||
## Cache layout & offline thumbnails
|
||
- Three cache families, and the split matters on activate: the **versioned shell
|
||
cache** `ytplayer-<BUILD_TAG>` is evicted on every deploy, while the **utility
|
||
caches** `ytplayer-thumbs` and `ytplayer-fonts` are listed in `UTILITY_CACHES`
|
||
and deliberately survive it. Adding a new utility cache means adding it there
|
||
too, or it gets wiped on the next deploy.
|
||
- **Thumbnails are cache-first, not stale-while-revalidate** — a given thumbnail
|
||
URL is immutable, so revalidating just burns a round trip per image per launch.
|
||
- **The opaque-response trap (this silently emptied the thumb cache for months).**
|
||
An `<img>` to another origin is a **no-cors** request, so `fetch(request)` in the
|
||
SW resolves to an **opaque** response with `status === 0` — not 200. The old
|
||
guard was `if (r.status === 200) cache.put(...)`, which rejected every single
|
||
thumbnail, so `ytplayer-thumbs` was permanently empty and offline showed broken
|
||
images (measured on prod: 0 entries after browsing pages full of visible thumbs).
|
||
Fix in `thumbnail()`: re-issue the request in `cors` mode — ytimg/ggpht all send
|
||
`Access-Control-Allow-Origin: *` — and cache that readable response; an opaque
|
||
one is accepted only as a last resort. **Never reintroduce a bare `status === 200`
|
||
check on a cross-origin subresource.**
|
||
- Thumbnail hosts live in `THUMB_HOSTS`. An unlisted host doesn't error — it just
|
||
bypasses the cache and breaks offline, so add mirrors/avatar hosts there.
|
||
- The thumb cache is capped at `THUMB_CACHE_MAX` (800, oldest-first via the
|
||
insertion-ordered `cache.keys()`). Keep a cap: CacheStorage and the OPFS offline
|
||
audio share one origin quota, and opaque entries are padded to ~7 MB each for
|
||
quota accounting, so an unbounded thumb cache can evict saved audio.
|
||
- App side (`app.js`): `warmThumb()` pulls artwork through the SW when a video is
|
||
saved offline, and `warmOfflineThumbs()` runs a bounded launch backfill
|
||
(`THUMB_WARM_MAX` = 400, 4 at a time) over cached ids + playlist videos so
|
||
libraries saved before this fix repair themselves. Thumbnails only cache when
|
||
something requests them — a device needs one online launch to get offline art.
|
||
- `staleWhileRevalidate()` (fonts) must not `return cached || networkFetch` bare:
|
||
the fetch resolves to `null` offline and `respondWith(null)` throws. It ends
|
||
with `|| Response.error()`.
|
||
|
||
## Data model quirks
|
||
- Client state persists in localStorage key **`_ytpdata`** and syncs (debounced
|
||
400 ms) to `POST /api/user/sync`, keyed by a browser fingerprint.
|
||
- **A-B loop markers are per-song-per-playlist**: stored on the playlist's own
|
||
copy of the video (`entry.ab = {a, b}`) when playback source is that playlist;
|
||
`data.abMarkers[videoId]` is only the fallback for non-playlist playback.
|
||
- **Online profiles** (`profiles` table, `/api/profile/*`): named cross-device
|
||
sync where the lowercase profile NAME is the only credential (passkey-style,
|
||
by design). Client stores `data.profile = {name, syncedAt}`; sync is
|
||
last-write-wins — push debounced on every persist(), pull on app launch when
|
||
the server's `updated_at` is newer than the local `syncedAt`.
|
||
- **Profile share links**: `?profile=<name>` is consumed by `adoptProfileFromUrl()`
|
||
at boot, before any rendering. It strips the param via `replaceState` (so a
|
||
reload can't re-fire it) and confirms first when the device already has
|
||
playlists/history or another profile — adopting *replaces* the synced slice.
|
||
The name comes off the URL untrusted, hence `escapeHtml()` on it.
|
||
- **Empty-home playlist grid**: `renderHomePlaylists()` swaps the branding hero in
|
||
`#playerPlaceholder` for the user's playlists (hero is the no-playlists
|
||
fallback). It is driven from the tail of `renderSidebar()` — not from
|
||
`render()` — so every playlist mutation refreshes both in one place.
|
||
|
||
## Testing
|
||
- Unit: **`node --test frontend/*.test.js`** (sw, sw-update, async-guard, video-edit).
|
||
Server: **`cd server && bun test`** (media-cache: real ffmpeg fixtures + a temp libsql DB).
|
||
Local e2e needs a CURRENT yt-dlp — a 2-month-old one 403s on every download.
|
||
The directory form `node --test frontend/` fails on Node 22 with
|
||
`Cannot find module .../frontend` — it resolves the dir as a module, not a test
|
||
glob. That's the harness, not the tests.
|
||
- E2E: `npx playwright test` — WebKit iPhone-12 profile against a static serve of
|
||
`frontend/` (needs `npx playwright install webkit`). A spurious update banner
|
||
will make the settings-panel specs fail with `#modal intercepts pointer events`
|
||
— that failure mode is a real app bug, not test flake. On the WSL laptop the
|
||
WebKit install fails host validation (missing `libgtk-4`, `libgstreamer*`, …,
|
||
needs `sudo npx playwright install-deps`); chromium is already downloaded, so
|
||
ad-hoc rendering/offline checks can drive it directly instead.
|
||
- Service-worker behaviour (thumb caching, offline) is only provable in a real
|
||
browser: serve `frontend/` statically, let the SW take control (needs a second
|
||
reload), then `context.setOffline(true)` and assert `img.naturalWidth > 0` plus
|
||
the `ytplayer-thumbs` entry count. Asserting against the browser's own HTTP
|
||
cache proves nothing — check the Cache API entry count.
|
||
- Test records on prod use `Probe */Recon *` names; clean via the container DB,
|
||
children (`video_history`) first.
|
||
|
||
## Harness
|
||
|
||
Skills live in `.agents/skills/` (symlinked into `.claude/skills/`):
|
||
- **deploy-prod** — the Dokploy deploy + buildTag verification flow (manual-only; use for any "deploy"/"release" request).
|
||
- **mobile-app-ui-design** — UI/UX design work on the PWA screens.
|
||
|
||
## Commit rules
|
||
One changeset = one commit, single-line imperative message, **no AI attribution
|
||
of any kind** (global rule). `git push origin main` pushes to both remotes.
|