waltz

README

Waltz

Transfer your playlists from Spotify to Youtube Music written in Go. Self hosted.

Usage

It's necessary to setup the API for Youtube and Spotify:

Spotify

Create a new project on developers.spotify.com. Make sure the redirect URI is: http://localhost:8080/auth/callback?provider=spotify. Add the client id and secret to the environment variables: SPOTIFY_ID, SPOTIFY_SECRET.

YouTube

Create a new project on console.cloud.google.com/. Under API & Services -> Credentials create a new OAuth Client Id, choose Web Application. Make sure the urls are these:

Under API & Allowed Services add Youtube Data Api V3. Add the client id and secret to the environment variables: GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET

Then just run the project with go run . and access the app on localhost:8080.

Limitations

Youtube gives a daily quota of 10.000 with each API call having a different cost. Currently for each playlist the operations costs are:

Operation	Intent	Cost
list playlists	Find if playlist already exists	1
insert playlist	Create playlist if it doesn't exist	50
list playlist items	Get existing tracks to not insert repeated tracks	1 for every 50 tracks
search	find videoId by name. Necessary to insert track	100
insert playlist item	Creates the track on the playlist	50

Which is limited to around 66 tracks daily. Even if the read data comes from another source, like a scrapper, the number would improve to only 200 at best.