Function startControlLoop

main.go:186–243

Starts an infinite loop where we poll for new websocket messages and react to them.

(wsConn *websocket.Conn, peerConnection *webrtc.PeerConnection, pendingCandidates *[]*webrtc.ICECandidate)

// Starts an infinite loop where we poll for new websocket messages and react to them.
func startControlLoop(wsConn *websocket.Conn, peerConnection *webrtc.PeerConnection, pendingCandidates *[]*webrtc.ICECandidate) {
	// Start loop here to read web socket messages
	for {

		messageType, message, err := wsConn.ReadMessage()
		if err != nil {
			log.Printf("Websocket read message error: %v", err)
			log.Printf("Closing Pion websocket control loop.")
			wsConn.Close()
			break
		}
		stringMessage := string(message)

		// We print the recieved messages in a different colour so they are easier to distinguish.
		colorGreen := "\033[32m"
		colorReset := "\033[0m"
		fmt.Println(string(colorGreen), fmt.Sprintf("Received message, (type=%d): %s", messageType, stringMessage), string(colorReset))

		// Transform the raw bytes into a map of string: []byte pairs, we can unmarshall each key/value as needed.
		var objmap map[string]json.RawMessage
		err = json.Unmarshal(message, &objmap)

		if err != nil {
			log.Printf("Error unmarshalling bytes from websocket message. Error: %s", err.Error())
			continue
		}

		// Get the type of message we received from the Unreal Engine side
		var pixelStreamingMessageType string
		err = json.Unmarshal(objmap["type"], &pixelStreamingMessageType)

		if err != nil {
			log.Printf("Error unmarshaling type from pixel streaming message. Error: %s", err.Error())
			continue
		}

		// Based on the "type" of message we received, we react accordingly.
		switch pixelStreamingMessageType {
		case "playerCount":
			var playerCount int
			err = json.Unmarshal(objmap["count"], &playerCount)
			if err != nil {
				log.Printf("Error unmarshaling player count. Error: %s", err.Error())
			}
			fmt.Println(fmt.Sprintf("Player count is: %d", playerCount))
		case "config":
			fmt.Println("Got config message, ToDO: react based on config that was passed.")
		case "answer":
			handleRemoteAnswer(message, peerConnection, wsConn, pendingCandidates)
		case "iceCandidate":
			candidateMsg := objmap["candidate"]
			handleRemoteIceCandidate(candidateMsg, peerConnection)
		default:
			log.Println("Got message we do not specifically handle, type was: " + pixelStreamingMessageType)
		}

	}
}