Spotify API for built-in server

spotilocal.js

'use strict'

const axios = require('axios')

const PORT = 4380
const DEFAULT_RETURN_ON = ['login', 'logout', 'play', 'pause', 'error', 'ap']

// Must use capitalized header
const ORIGIN_HEADER = { 'Origin': 'https://open.spotify.com' }

// ------------------
//      Helpers
// ------------------
const getJson = async (url, params = {}, headers = {}) => {
  const { data } = await axios.get(url, { params, headers })
  return data
}

const url = uri => `http://localhost:${PORT}${uri}`

const spotilocal = async () => {
  const getCsrfToken = async () => {
    const { token } = await getJson(url('/simplecsrf/token.json'), null, ORIGIN_HEADER)
    return token
  }

  const getOauthToken = async () => {
    const { t } = await getJson('https://open.spotify.com/token')
    return t
  }

  const getTokens = async () => {
    const [csrfToken, oauthToken] = await Promise.all([
      getCsrfToken(),
      getOauthToken()
    ])
    return { csrfToken, oauthToken }
  }

  const getVersion = () =>
    getJson(
      url('/service/version.json'),
      { service: 'remote' },
      ORIGIN_HEADER
    )

  const openSpotifyClient = async () =>
    getJson(url('/remote/open.json'), null, ORIGIN_HEADER)

  await openSpotifyClient()
  const { csrfToken, oauthToken } = await getTokens()

  const getStatus = async (returnAfter = 59, returnOn = DEFAULT_RETURN_ON) =>
    getJson(url('/remote/status.json'), {
      oauth: oauthToken,
      csrf: csrfToken,
      returnafter: returnAfter,
      returnon: returnOn.join(',')
    }, ORIGIN_HEADER)

  const pause = async (pause = true) =>
    getJson(url('/remote/pause.json'), {
      oauth: oauthToken,
      csrf: csrfToken,
      pause
    }, ORIGIN_HEADER)

  const unpause = async pause => pause(false)

  const play = async spotifyUri =>
    getJson(url('/remote/play.json'), {
      'oauth': oauthToken,
      'csrf': csrfToken,
      'uri': spotifyUri,
      'context': spotifyUri
    }, ORIGIN_HEADER)

  return {
    getVersion,
    getStatus,
    openSpotifyClient,
    pause,
    unpause,
    play
  }
}

module.exports = spotilocal

// ------------------
//      Example
// ------------------
const onLoad = async spotify => {
  let paused = false

  false && setInterval(() => {
    paused = !paused
    spotify.pause(paused)
  }, 150)

  const songs = [
    'spotify:track:5nAFaDOTL6fkvtlklzviHD',
    'spotify:track:7CpHzlFSAAFegZveUFNHzH',
    'spotify:track:6TUPCXGsj3HQAKn29KcrL4',
    'spotify:track:0t2myRMEMCi2SRyg5TEFLp',
    'spotify:track:6sqo5lYZ3yJRv0auIWBNrm',
    'spotify:track:2w7pHPE7Ak0zc4keLZ2clK',
    'spotify:track:0Z21JPecgmeXFYTzxgdmPq'
  ]

  const playSongs = async (index = 0, timeout = 2000) => {
    if (!songs[index]) index = 0
    try {
      const { track } = await spotify.play(songs[index])
      console.log(track.track_resource.name)
    } catch (e) {
      console.error('ERROR:', e.message)
    } finally {
      setTimeout(() => playSongs(++index), timeout)
    }
  }

  playSongs()

  process.on('SIGINT', async () => {
    await spotify.pause()
    process.exit()
  })
}

;(async () => {
  const spotify = await spotilocal()
  onLoad(spotify)
})()