Subsonic / Navidrome Integration

NullPlayer supports Subsonic-compatible servers (including Navidrome) for music streaming, browsing, and scrobbling.

Architecture

File	Purpose
Subsonic/SubsonicModels.swift	Domain models (Server, Artist, Album, Song, Playlist, MusicFolder) and API DTOs
Subsonic/SubsonicServerClient.swift	HTTP client for Subsonic REST API
Subsonic/SubsonicManager.swift	Singleton managing connections, caching, music folder selection, and track conversion

Authentication

Token-based auth is used (Subsonic API 1.13.0+):

GET /rest/{endpoint}?u={username}&t={md5(password+salt)}&s={salt}&v=1.16.1&c=NullPlayer&f=json

• t = MD5 hash of password + salt
• s = random salt string (16 chars)
• f=json added to all API requests (omitted for stream/binary endpoints)

Music Folders

Navidrome/Subsonic can have multiple music folders (root library directories).

• Fetch: GET /rest/getMusicFolders — returns all configured music folders
• SubsonicMusicFolder: { id: String, name: String }
• SubsonicManager.musicFolders — available folders fetched on connect
• SubsonicManager.currentMusicFolder — nil means all folders; posts musicFolderDidChangeNotification on change
• selectMusicFolder(_ folder:) — sets folder, clears cache, triggers preload
• clearMusicFolderSelection() — resets to nil (all folders), clears cache, triggers preload
• Persisted via SubsonicCurrentMusicFolderID UserDefaults key
• Auto-selection on connect: saved ID → nil (all folders, valid default)
• musicFolderId is passed to getArtists and getAlbumList2 when a folder is selected

Library Browser UI

The "Lib:" zone in the status bar shows the current folder name ("All" when nil). Click to open a folder picker menu.

API Endpoints

Library Browsing

• Artists: GET /rest/getArtists?musicFolderId={id} — indexed A-Z; musicFolderId optional
• Artist detail: GET /rest/getArtist?id={artistId} — returns artist + album list
• Albums: GET /rest/getAlbumList2?type={type}&size={n}&offset={n}&musicFolderId={id} — musicFolderId optional
• Album detail: GET /rest/getAlbum?id={albumId} — returns album + track list
• Song: GET /rest/getSong?id={songId}
• Search: GET /rest/search3?query={q}&artistCount={n}&albumCount={n}&songCount={n}
• Playlists: GET /rest/getPlaylists
• Playlist detail: GET /rest/getPlaylist?id={playlistId}
• Starred: GET /rest/getStarred2

Album List Types (getAlbumList2)

Type	Description
alphabeticalByName	A-Z by album title
alphabeticalByArtist	A-Z by artist
newest	Recently added
frequent	Most played
recent	Recently played
starred	Favorited albums
random	Random selection
byYear	By release year
byGenre	By genre

Streaming & Images

• Stream: GET /rest/stream?id={songId} — omit f=json; Navidrome returns binary
• Cover art: GET /rest/getCoverArt?id={coverArtId}&size={px} — omit f=json

User Actions

• Star: GET /rest/star?id={songId} / albumId={id} / artistId={id}
• Unstar: GET /rest/unstar?id={songId} / albumId={id} / artistId={id}
• Rate: GET /rest/setRating?id={songId}&rating={1-5} (0 = remove)
• Scrobble: GET /rest/scrobble?id={songId}&submission=true

State Persistence

• Current server ID: SubsonicCurrentServerID (UserDefaults)
• Current music folder ID: SubsonicCurrentMusicFolderID (UserDefaults) — nil = all folders
• Credentials: macOS login keychain via KeychainHelper (key: subsonic_servers) — uses permissive SecAccessCreate ACL; do NOT add kSecUseDataProtectionKeychain (breaks ad-hoc DMG builds with -34018)

Notifications

Notification	Posted when
serversDidChangeNotification	servers array changes
connectionStateDidChangeNotification	Connection state changes
libraryContentDidPreloadNotification	Background preload completes
musicFolderDidChangeNotification	currentMusicFolder changes

Track Identification

Subsonic tracks in the playlist are identified by:

• track.subsonicId — the Subsonic song ID
• track.subsonicServerId — which server the track belongs to

Scrobbling

Scrobble threshold: 50% of track duration or 4 minutes, whichever comes first. Reports "now playing" immediately on start via scrobble(id:submission:false).

Casting (Sonos)

Subsonic streaming URLs contain auth query parameters which Sonos cannot handle. NullPlayer proxies audio through LocalMediaServer before casting. Stream URLs also omit f=json so Navidrome returns binary audio data.

Key Gotchas

• f=json on stream endpoints: Always use streamAuthParams() (not authParams()) for stream/image URLs — these omit f=json which would otherwise cause Navidrome to return JSON instead of binary data
• musicFolderId scoping: When a music folder is selected, pass its ID to both getArtists and getAlbumList2. The folder filter is applied server-side; client cache is cleared on folder change to avoid showing stale cross-folder content
• Folder IDs are integers server-side: The Subsonic API returns id as an integer in getMusicFolders. SubsonicMusicFolder stores it as String (converted from Int in the DTO) for consistency with other IDs
• Library selector in browser: The "Lib:" click zone in both ModernLibraryBrowserView and classic PlexBrowserView opens an "All Folders" + folders picker for Subsonic/Navidrome sources. SubsonicManager tracks musicFolders: [SubsonicMusicFolder] and currentMusicFolder: SubsonicMusicFolder? (nil = all folders). Posts musicFolderDidChangeNotification on change; persisted via SubsonicCurrentMusicFolderID UserDefaults key.
• Streaming URL content type (Sonos): Subsonic stream URLs (/rest/stream?id=...) have no file extension, so detectAudioContentType(for:) defaults to audio/mpeg. This breaks Sonos casting for non-MP3 formats and can let high-resolution lossless tracks bypass format filtering. Prefer Track.contentType set by the server client from API metadata. Preserve samplingRate too: strict Sonos compatibility rejects extensionless FLAC/WAV above 48 kHz, and rejects unknown-rate FLAC/WAV conservatively when no sample rate is available.