feat: subsonic library pagination

server/src/subsonic.ts

@@ -71,4 +71,25 @@ export class SubsonicClient {
   async ping(): Promise<void> {
     await this.request('ping')
   }
+
+  async getAllAlbums(
+    onProgress?: (albums: SubsonicAlbum[], done: number) => void
+  ): Promise<SubsonicAlbum[]> {
+    const all: SubsonicAlbum[] = []
+    const pageSize = 500
+    for (let offset = 0; ; offset += pageSize) {
+      const envelope = await this.request('getAlbumList2', {
+        type: 'alphabeticalByName',
+        size: String(pageSize),
+        offset: String(offset),
+      })
+      const list: any[] = envelope.albumList2?.album ?? []
+      for (const a of list) {
+        all.push({ id: String(a.id), title: a.name ?? a.title ?? '', artist: a.artist ?? '' })
+      }
+      onProgress?.(all, all.length)
+      if (list.length < pageSize || all.length > 20000) break
+    }
+    return all
+  }
 }

server/test/subsonic.test.ts

@@ -0,0 +1,99 @@
+import { describe, it, expect } from 'vitest'
+import { SubsonicClient, SubsonicError } from '../src/subsonic.js'
+
+function subsonicResponse(body: object, status = 200): Response {
+  return new Response(JSON.stringify(body), {
+    status,
+    headers: { 'content-type': 'application/json' },
+  })
+}
+
+function albumPage(count: number, offset: number) {
+  return {
+    'subsonic-response': {
+      status: 'ok',
+      albumList2: {
+        album: Array.from({ length: count }, (_, i) => ({
+          id: offset + i + 1,
+          name: `Album ${offset + i + 1}`,
+          artist: `Artist ${Math.floor((offset + i) / 10)}`,
+        })),
+      },
+    },
+  }
+}
+
+describe('SubsonicClient', () => {
+  it('ping sends auth params and succeeds', async () => {
+    const seen: string[] = []
+    const c = new SubsonicClient({
+      url: 'http://navidrome.local',
+      username: 'sam',
+      password: 'pass',
+      fetchImpl: (async (input: any) => {
+        seen.push(String(input))
+        return subsonicResponse({ 'subsonic-response': { status: 'ok' } })
+      }) as typeof fetch,
+    })
+    await c.ping()
+    expect(seen[0]!).toContain('/rest/ping')
+    expect(seen[0]!).toContain('u=sam')
+    expect(seen[0]!).toContain('v=1.16.1')
+    expect(seen[0]!).toContain('c=record-shop')
+    expect(seen[0]!).toContain('f=json')
+    expect(seen[0]!).toMatch(/t=[0-9a-f]{32}/)
+  })
+
+  it('ping raises auth error on failed status with code 40', async () => {
+    const c = new SubsonicClient({
+      url: 'http://x',
+      username: 'sam',
+      password: 'bad',
+      fetchImpl: (async () =>
+        subsonicResponse({
+          'subsonic-response': {
+            status: 'failed',
+            error: { code: 40, message: 'Wrong username or password.' },
+          },
+        })) as typeof fetch,
+    })
+    const err = await c.ping().catch((e) => e)
+    expect(err).toBeInstanceOf(SubsonicError)
+    expect((err as SubsonicError).code).toBe('auth')
+  })
+
+  it('getAllAlbums paginates until a short page', async () => {
+    const seen: string[] = []
+    const c = new SubsonicClient({
+      url: 'http://navidrome.local',
+      username: 'sam',
+      password: 'pass',
+      fetchImpl: (async (input: any) => {
+        const url = new URL(String(input))
+        seen.push(url.searchParams.get('offset') ?? '')
+        const offset = Number(url.searchParams.get('offset') ?? 0)
+        // first page: 500 albums, second: 3, third never requested
+        return subsonicResponse(offset === 0 ? albumPage(500, 0) : albumPage(3, 500))
+      }) as typeof fetch,
+    })
+    const albums = await c.getAllAlbums()
+    expect(seen).toEqual(['0', '500'])
+    expect(albums).toHaveLength(503)
+    expect(albums[0]!).toEqual({ id: '1', title: 'Album 1', artist: 'Artist 0' })
+  })
+
+  it('getAllAlbums reports progress', async () => {
+    const c = new SubsonicClient({
+      url: 'http://x',
+      username: 'sam',
+      password: 'pass',
+      fetchImpl: (async (input: any) => {
+        const offset = Number(new URL(String(input)).searchParams.get('offset') ?? 0)
+        return subsonicResponse(offset === 0 ? albumPage(500, 0) : albumPage(3, 500))
+      }) as typeof fetch,
+    })
+    const progress: number[] = []
+    await c.getAllAlbums((_albums, done) => progress.push(done))
+    expect(progress[progress.length - 1]!).toBe(503)
+  })
+})