Support spotify's get-audio-features api endpoint

[ikirmitz]

Is your feature request related to a problem? Please describe.
Spotify calculates and stores a host of audio features for a track which are retrievable through the get-audio-features api
Currently there doesn't seems to be a way to retrieve these features using the API provided by librespot-java

Describe the solution you'd like
Allow retrieval of a track's audio features through the /metadata/{type}/{uri} or /metadata/{uri} endpoints or maybe through a completely new endpoint such as /audio-features/{uri}

Additional resources
More info here https://developer.spotify.com/documentation/web-api/reference/tracks/get-audio-features/

[devgianlu]

Unluckily this data isn't provided inside the client with an internal API endpoint. You need to use the public API to retrieve audio features.

[ikirmitz]

Yeah that's what I meant. Hence the Feature request. Apologies if that wasn't clear :(
Hopefully that's something you'll consider adding but until then I'll keep using the public spotify api
Thank you for your prompt response as always

[devgianlu]

What I could do is add an endpoint that resolves all the endpoints from the public API. Would that be a solution for you?

You could do POST http://localhost:24879/web-api/v1/audio-features/{id} and librespot-java will add the Authorization header.

[ikirmitz]

That is an amazing solution. Non having to deal a separate authentication is ideal!!

[devgianlu]

@ikirmitz I've made the changes, let me know if it works for you.

[ikirmitz]

It works perfectly. Thank you!