Jellyfin-compatible API

Rockbox can act as a Jellyfin server for native Jellyfin clients on your LAN. Internally it’s a thin actix-web shim over the same rockbox-library SQLite database the Subsonic API reads from — there’s no separate scan, no separate user store, and no extra daemon to manage.

Enabling

Set jellyfin_port in ~/.config/rockbox.org/settings.toml:

subsonic_username = "admin"
subsonic_password = "changeme"
jellyfin_port     = 8096      # conventional Jellyfin port; pick any free port

Then rockbox restart. The server is disabled when jellyfin_port is missing or when subsonic_password is empty — credentials are shared with the Subsonic side.

Discovery

When enabled, two discovery mechanisms run alongside the HTTP server:

mDNS: _jellyfin._tcp.local. is advertised on the configured port, with a ID=… TXT record matching the server’s stable Jellyfin id.
UDP 7359: the server binds the standard Jellyfin client-discovery port and answers the literal probe "Who is JellyfinServer?" with a JSON response containing the server’s LAN URL.

Both run automatically; nothing to configure.

Tested clients

Client	Platform	Notes
Finamp	Android/iOS	Best-tested music client. Full browse + stream + scrobble.
Symfonium	Android	Paid. Works against the Jellyfin API.
Amcfy Music	Android	Triggers library refresh on `ScheduledTasks/Running`.
Findroid	Android	Video-focused; will show empty libraries because Rockbox is audio-only.
Streamyfin	Android	Polls `/Sessions`; works.
Official app	Android	Not supported — the official app is a WebView around the Jellyfin web UI, which Rockbox doesn’t ship.

For music, use Finamp (or Amcfy / Symfonium).

Endpoint surface

The server implements enough of the Jellyfin OpenAPI to satisfy the native music clients above. All authenticated routes accept the token via X-Emby-Token header, Authorization: MediaBrowser Token="…", or ?api_key=… on streaming URLs. Query parameters work in both camelCase (?parentId=…) and PascalCase (?ParentId=…); repeated keys (?includeItemTypes=Audio&includeItemTypes=MusicAlbum) are concatenated.

Group	Endpoints
System	`GET /System/Info`, `GET /System/Info/Public`, `GET /System/Endpoint`
Auth	`POST /Users/AuthenticateByName` (+ `authenticatebyname` lowercase alias)
Users	`GET /Users`, `GET /Users/Public`, `GET /Users/Me`, `GET /Users/{id}`
Views	`GET /Users/{id}/Views`, `GET /UserViews`, `GET /Library/MediaFolders`
Items	`GET /Items`, `GET /Users/{id}/Items`, `GET /Items/{id}`, `GET /Items/Latest`, `GET /Items/Suggestions`, `GET /Items/{id}/File`, `GET /Items/{id}/Download`, `GET /Items/{id}/Images/{kind}`
Audio	`GET /Audio/{id}/stream`, `/stream.{ext}`, `/universal` (Range-aware)
Artists	`GET /Artists`, `GET /Artists/AlbumArtists`, `GET /Artists/{name}`
Search	`GET /Search/Hints`, `GET /Items?searchTerm=…`
Playback	`GET POST /Items/{id}/PlaybackInfo`
Sessions	`GET /Sessions`, `POST /Sessions/Capabilities/Full`, `POST /Sessions/Playing{,/Progress,/Stopped}`
Tasks	`POST /ScheduledTasks/Running/{id}`, `POST /Library/Refresh`
Discovery	UDP `7359` probe responder, mDNS `_jellyfin._tcp.local.` advertisement

Item IDs are deterministic dashed UUIDs derived from the native Artist/Album/Track ids, and round-tripped via a jf_guids lookup table so subsequent requests resolve back to the right row.

Quick test

# Discover the server (or just `curl http://<host>:8096/System/Info/Public`)
echo -n 'Who is JellyfinServer?' | nc -u -w1 -b 255.255.255.255 7359

# Authenticate
TOKEN=$(curl -s -X POST http://localhost:8096/Users/AuthenticateByName \
  -H 'Content-Type: application/json' \
  -H 'Authorization: MediaBrowser Client="curl", Device="d", DeviceId="i", Version="0.1"' \
  -d '{"Username":"admin","Pw":"changeme"}' \
  | jq -r .AccessToken)

# List libraries (returns the synthetic "Music" CollectionFolder)
curl -s -H "X-Emby-Token: $TOKEN" "http://localhost:8096/Users/me/Views" | jq

# List all artists
curl -s -H "X-Emby-Token: $TOKEN" \
  "http://localhost:8096/Items?includeItemTypes=MusicArtist" | jq '.Items[].Name'

What’s not supported

Video — Rockbox is an audio-only player. Video libraries and the /Videos/{id}/stream endpoint family are not implemented.
Transcoding — only direct play. MediaSource.SupportsTranscoding is false; clients must support the container natively.
WebSocket notifications (/socket) — clients fall back to polling /Sessions, which is supported.
Multi-user — there is a single synthetic user matching subsonic_username. Token storage is real (persisted in jellyfin_tokens), but every token belongs to the same user.
Playlists, lyrics, parental ratings, sync, live TV — out of scope.

Overview

HTTP REST

Enabling

Discovery

Tested clients

Endpoint surface

Quick test

What’s not supported

​Enabling

​Discovery

​Tested clients

​Endpoint surface

​Quick test

​What’s not supported

Enabling

Discovery

Tested clients

Endpoint surface

Quick test

What’s not supported