ComunicRTCProxy/ws.go

// Websocket controller
//
// @author Pierre HUBERT

package main

import (
	"encoding/json"
	"fmt"
	"log"
	"os"
	"os/signal"

	"github.com/gorilla/websocket"
)

// WsMessage is a message from or to the api server
type WsMessage struct {
	Title    string      `json:"title"`
	CallHash string      `json:"callHash"`
	PeerID   string      `json:"peerId"`
	Data     interface{} `json:"data"`
}

var outMsgChan = make(chan interface{})

// Open websocket connection
func openWs(conf *Config) {

	// Auto-close connection when the system request it
	interrupt := make(chan os.Signal, 1)
	signal.Notify(interrupt, os.Interrupt)

	u := conf.getURL()
	log.Printf("Connecting to %s", u.String())

	// Connect to Websocket
	c, _, err := websocket.DefaultDialer.Dial(u.String(), nil)
	if err != nil {
		log.Println("dial:", err)
		return
	}
	defer c.Close()

	// Wait for interrupt signal
	go func() {
		<-interrupt
		c.Close()
	}()

	// Send outgoing messages
	go func() {
		for {
			c.WriteJSON(<-outMsgChan)
		}
	}()

	// Read remote messages
	for {

		_, message, err := c.ReadMessage()

		if err != nil {
			log.Printf("WS Read error: %s", err.Error())
			return
		}

		// Process incoming messages

		// Decode JSON
		var msg WsMessage
		json.Unmarshal(message, &msg)

		switch msg.Title {

		// call configuration
		case "config":
			println("Got call configuration")
			setCallConfig(msg.Data.(map[string]interface{}))
			fmt.Println("Enable video calls:", callConf.allowVideo)
			break

		// Remote signal
		case "signal":
			onSignal(msg.CallHash, msg.PeerID, msg.Data.(map[string]interface{}))
			break

		// Request an offer
		case "request_offer":
			onRequestOffer(msg.CallHash, msg.PeerID)
			break

		// Close a connection
		case "close_conn":
			onCloseConnection(msg.CallHash, msg.PeerID)
			break

		default:
			println("Received unkown message type!")
			log.Printf("recv: %s", message)
			break
		}
	}

}

/// Send a signal to the API
func sendSignal(callHash, peerID string, data interface{}) {

	msg := WsMessage{
		Title:    "signal",
		PeerID:   peerID,
		CallHash: callHash,
		Data:     data,
	}

	outMsgChan <- msg
}