Show which song you're currently listening to on your website.
Visit the Spotify Developer site, create an app and note your Client ID and Client Secret down somewhere or add it to the JSON file I'm providing. Also add a redirect uri. Example would be https://www.google.com/. Just make sure to encode the URL for step 2.
Update this link with your client_id:
https://accounts.spotify.com/authorize?response_type=code&client_id=CLIENTIDGOESHERE&scope=playlist-modify-private&redirect_uri=https%3A%2F%2Fwww.google.de%2F -> modify the scope if needed.
The access code should be now seen in the URL. https://www.google.com/?code=YOURCODESHOULDBEHERE Write the access code down somewhere or add it to the JSON file I'm providing.
Running this CURL command should return a JSON string with your refresh token inside.
curl -d client_id=CLIENTIDGOESHERE -d client_secret=CLIENTSECRETGOESHERE -d grant_type=authorization_code -d code=CODE -d redirect_uri=https%3A%2F%2Fwww.google.de%2F https://accounts.spotify.com/api/token
Place the refresh token into the JSON file I'm providing and you're good to go!