Audiobook.js

let clientID = '<client_id>'
let clientSecret = '<client_secret>'
let cred = clientID + ':' + clientSecret
let credEncoded = Data.fromString(cred).toBase64String()
let auth = 'Basic ' + credEncoded

// Get token
let tokenURL = 'https://accounts.spotify.com/api/token'
var reqToken = new Request(tokenURL)
reqToken.method = 'POST'
reqToken.body = 'grant_type=client_credentials&undefined='
reqToken.headers = {
  'Content-Type': 'application/x-www-form-urlencoded',
  'Authorization': auth
}

let res = await reqToken.loadJSON()
let token = res['access_token']
let auth2 = 'Bearer ' + token

// Params
var num = URLScheme.parameter('number')
var q = ''
if (parseInt(num) < 10 ) {
    q = encodeURI(':00' + num + '/')
} else if (parseInt(num) < 100) {
    q = encodeURI(':0' + num + '/')
  } else if (parseInt(num) < 1000) {
    q = encodeURI(':') + encodeURI(num) + '/'
} 

let artist = encodeURI(':Die drei ???')
let endpoint = 'https://api.spotify.com/v1/search?q=album' + q + '&artist' + artist + '&type=album&limit=1' 
let method = 'GET'
let headers = {
  'Accept': 'application/json',
  'Content-Type': 'application/json',
  'Authorization': auth2
}

// Make the request
let req = new Request(endpoint)
req.method = method
req.headers = headers

// Get the track URL
let json = await req.loadJSON()
console.log(json)

var finalURL = json['albums']['items'][0]['external_urls']['spotify']

// Open the track on Spotify
Safari.open(finalURL)