api.js

1	const apiExpiry = 3600 * 1000; // 1 hour
2
3	function createCallbackState(processedCount, totalCount) {
4	return {
5	processedCount: processedCount,
6	totalCount: totalCount
7	};
8	}
9
10	async function getAlbums(statusCallback) {
11	const db = await openDb();
12	const cacheKey = 'albums';
13	const cachedAlbums = await getWithExpiry(db, cacheKey);
14	if (cachedAlbums) {
15	if (statusCallback) {
16	statusCallback(createCallbackState(cachedAlbums.length, cachedAlbums.length))
17	}
18	return cachedAlbums;
19	}
20
21	const accessToken = await getAccessToken();
22	const albums = [];
23	let url = 'https://api.spotify.com/v1/me/albums?limit=50';
24	while (url) {
25	const response = await fetch(url, {
26	headers: {
27	Authorization: 'Bearer ' + accessToken
28	}
29	});
30	const data = await response.json();
31	albums.push(...data.items);
32	if (statusCallback) {
33	statusCallback(createCallbackState(albums.length, data.total))
34	}
35	url = data.next;
36	}
37
38	await setWithExpiry(db, cacheKey, albums, apiExpiry);
39	return albums;
40	}
41
42	async function batchGetTracks(albumIds, statusCallback) {
43	const batchSize = 20
44	if (albumIds.length == 0) {
45	return [];
46	}
47	if (albumIds.length > batchSize) {
48	const allTracks = []
49	while (albumIds.length > 0) {
50	const batch = albumIds.splice(0, batchSize);
51	albumIds = albumIds.splice(batchSize);
52	const tracks = await batchGetTracks(batch, statusCallback);
53	allTracks.push(...tracks);
54	}
55	return allTracks;
56	}
57
58	const db = await openDb();
59	const cacheKey = `tracks-${albumIds.join('-')}`;
60	const cachedTracks = await getWithExpiry(db, cacheKey);
61	if (cachedTracks) {
62	if (statusCallback) {
63	statusCallback(createCallbackState(cachedTracks.length, cachedTracks.length))
64	}
65	return cachedTracks;
66	}
67
68	const tracks = [];
69	const accessToken = await getAccessToken();
70	let url = `https://api.spotify.com/v1/albums?ids=${albumIds.join(',')}&market=from_token`;
71	while (url) {
72	const response = await fetch(url, {
73	headers: {
74	Authorization: 'Bearer ' + accessToken
75	}
76	});
77	const data = await response.json();
78	data.albums.forEach(album => {
79	// combine the album data with the track data
80	tracks.push(...album.tracks.items.map(track => {
81	track.album = {
82	id: album.id,
83	name: album.name,
84	images: album.images,
85	external_urls: album.external_urls
86	}
87	return track;
88	}));
89	});
90	if (statusCallback) {
91	statusCallback(createCallbackState(tracks.length, tracks.length))
92	}
93	url = data.next;
94	}
95
96	await setWithExpiry(db, cacheKey, tracks, apiExpiry);
97	return tracks;
98	}
99
100	async function getTracks(albumId, statusCallback) {
101	const db = await openDb();
102	const cacheKey = `tracks-${albumId}`;
103	const cachedTracks = await getWithExpiry(db, cacheKey);
104	if (cachedTracks) {
105	if (statusCallback) {
106	statusCallback(createCallbackState(cachedTracks.length, cachedTracks.length))
107	}
108	return cachedTracks;
109	}
110
111	const tracks = [];
112	const accessToken = await getAccessToken();
113	let url = `https://api.spotify.com/v1/albums/${albumId}/tracks?limit=50`;
114	while (url) {
115	const response = await fetch(url, {
116	headers: {
117	Authorization: 'Bearer ' + accessToken
118	}
119	});
120	const data = await response.json();
121	tracks.push(...data.items);
122	if (statusCallback) {
123	statusCallback(createCallbackState(tracks.length, data.total))
124	}
125	url = data.next;
126	}
127
128	await setWithExpiry(db, cacheKey, tracks, apiExpiry);
129	return tracks;
130	}
131
132	async function playTrack(trackId) {
133	let accessToken = await getAccessToken();
134	console.info(`Playing track ${trackId}`);
135	const response = await fetch(`https://api.spotify.com/v1/me/player/play`, {
136	method: 'PUT',
137	headers: {
138	Authorization: 'Bearer ' + accessToken
139	},
140	body: JSON.stringify({
141	uris: [`spotify:track:${trackId}`]
142	})
143	});
144	if (response.status != 204) {
145	const json = await response.json();
146	throw new Error(`Failed to play track ${trackId}: ${response.status}\n${JSON.stringify(json)}`);
147	}
148	}
149
150	async function getPlayingTrack() {
151	const accessToken = await getAccessToken();
152	const response = await fetch("https://api.spotify.com/v1/me/player", {
153	headers: {
154	Authorization: 'Bearer ' + accessToken
155	}
156	});
157
158	if (response.status == 204) {
159	return null;
160	}
161
162	const data = await response.json();
163	return data;
164	}
165
166	async function play() {
167	const accessToken = await getAccessToken();
168	await fetch("https://api.spotify.com/v1/me/player/play", {
169	method: "PUT",
170	headers: {
171	Authorization: 'Bearer ' + accessToken
172	}
173	});
174	}
175
176	async function pause() {
177	const accessToken = await getAccessToken();
178	await fetch("https://api.spotify.com/v1/me/player/pause", {
179	method: "PUT",
180	headers: {
181	Authorization: 'Bearer ' + accessToken
182	}
183	});
184	}
185
186	async function getAvailableDevices() {
187	const accessToken = await getAccessToken();
188	const response = await fetch("https://api.spotify.com/v1/me/player/devices", {
189	headers: {
190	Authorization: 'Bearer ' + accessToken
191	}
192	});
193	const data = await response.json();
194	return data.devices;
195	}
196
197	async function transferPlayback(deviceId) {
198	const accessToken = await getAccessToken();
199	const response = await fetch("https://api.spotify.com/v1/me/player", {
200	method: "PUT",
201	headers: {
202	Authorization: 'Bearer ' + accessToken
203	},
204	body: JSON.stringify({
205	device_ids: [deviceId]
206	})
207	});
208	if (response.status != 204) {
209	const json = await response.json();
210	throw new Error(`Failed to transfer playback to ${deviceId}: ${response.status}\n${JSON.stringify(json)}`);
211	}
212	}