WebSocket relay

The relay is an outbound WebSocket from Encore to a server you run. Every event Soloist emits is republished to it, and every message the server sends back is passed to Soloist as a command.

Use it to get live playback and full control into a web app hosted somewhere else. The Pi connects out, so you don't open any inbound ports or poll the Spotify Web API.

Spotify app ──Connect──▶ Soloist ⇄ Encore ══ outbound wss:// ══▶ your server ⇄ your users

Set it up in Settings → WebSocket Relay.

Options

Setting	Config key	Notes
Relay URL	relay.url	ws:// or wss://. Empty turns the relay off.
Authorization Header	relay.authorization	Optional. Sent verbatim as the Authorization header when connecting, e.g. Bearer abc123.
Pusher protocol	relay.pusher	Wraps frames in the Pusher protocol. See Pusher & Laravel Reverb.
Channel	relay.channel	Pusher only.
App key / App secret	relay.app_key, relay.app_secret	Pusher only, for signing private and presence channels.

The section shows the connection state and last error. If the connection drops, Encore reconnects with backoff.

What's sent

In plain mode, Soloist's frames are forwarded verbatim: the same JSON that clients of the control WebSocket receive, such as track_changed, playback_state and volume_changed. Messages your server sends are passed straight to Soloist, so they use Soloist's command format. See the Soloist documentation.

Security

The relay server has full control

Anything your relay server sends is executed by Soloist: play, pause, skip, volume. There's no per-message check. Treat the server like a client holding the auth token. Use wss:// and an Authorization header, and only point the relay at a server you control.

relay:
  url: "wss://example.com/relay"
  authorization: "Bearer change-me"
  pusher: false