websocket

Overview ¶

Package websocket upgrades HTTP connections to WebSocket connections and manages the resulting connection. It has no business logic: callers write their own read loop, decide what messages mean, and own any application concepts (rooms, hubs, auth) on top of the raw Conn.

WebSocket.Upgrade performs the HTTP-to-WebSocket handshake and returns a Conn. Conn.ReadMessage blocks for the next inbound frame and must be used from a single goroutine. Write, WriteMessage, and WriteJSON are safe for concurrent use: a mutex serializes them onto the underlying connection and each call blocks until its frame is written or WriteTimeout elapses. A background goroutine pings the peer every PingInterval; a peer that stops answering trips the read deadline, which surfaces as an error from ReadMessage.

Basic usage:

ws, err := websocket.New(&websocket.Config{AllowedOrigins: []string{"https://example.com"}})
if err != nil {
	log.Fatal(err)
}

e.GET("/ws", func(c echo.Context) error {
	conn, err := ws.Upgrade(c.Response(), c.Request())
	if err != nil {
		return err
	}
	defer conn.Close()

	for {
		_, data, err := conn.ReadMessage()
		if err != nil {
			return nil
		}
		// caller decides what data means
	}
})