Handle websocket

web/handler.go

@@ -21,76 +21,20 @@ var (
 	validPath = regexp.MustCompile("^/[a-z0-9@_-]*$")
 )
 
-// Handle WebRTC session description exchange via POST
-func viewerPostHandler(w http.ResponseWriter, r *http.Request) {
-	// Limit response body to 128KB
-	r.Body = http.MaxBytesReader(w, r.Body, 131072)
-
-	// Get stream ID from URL, or from domain name
-	path := r.URL.Path[1:]
-	host := r.Host
-	if strings.Contains(host, ":") {
-		realHost, _, err := net.SplitHostPort(r.Host)
-		if err != nil {
-			log.Printf("Failed to split host and port from %s", r.Host)
-			return
-		}
-		host = realHost
-	}
-	host = strings.Replace(host, ".", "-", -1)
-	if streamID, ok := cfg.MapDomainToStream[host]; ok {
-		path = streamID
-	}
-
-	// Decode client description
-	dec := json.NewDecoder(r.Body)
-	dec.DisallowUnknownFields()
-	remoteDescription := webrtc.SessionDescription{}
-	if err := dec.Decode(&remoteDescription); err != nil {
-		http.Error(w, "The JSON WebRTC offer is malformed", http.StatusBadRequest)
+// Handle site index and viewer pages
+func viewerHandler(w http.ResponseWriter, r *http.Request) {
+	// Validation on path
+	if validPath.FindStringSubmatch(r.URL.Path) == nil {
+		http.NotFound(w, r)
+		log.Printf("Replied not found on %s", r.URL.Path)
 		return
 	}
 
-	// Get requested stream
-	stream, err := streams.Get(path)
-	if err != nil {
-		http.Error(w, "Stream not found", http.StatusNotFound)
-		log.Printf("Stream not found: %s", path)
-		return
+	// Check method
+	if r.Method != http.MethodGet {
+		http.Error(w, "Method not allowed.", http.StatusMethodNotAllowed)
 	}
 
-	// Get requested quality
-	// FIXME: extract quality from request
-	qualityName := "source"
-	q, err := stream.GetQuality(qualityName)
-	if err != nil {
-		http.Error(w, "Quality not found", http.StatusNotFound)
-		log.Printf("Quality not found: %s", qualityName)
-		return
-	}
-
-	// Exchange session descriptions with WebRTC stream server
-	q.WebRtcRemoteSdp <- remoteDescription
-	localDescription := <-q.WebRtcLocalSdp
-
-	// Send server description as JSON
-	jsonDesc, err := json.Marshal(localDescription)
-	if err != nil {
-		http.Error(w, "An error occurred while formating response", http.StatusInternalServerError)
-		log.Println("An error occurred while sending session description", err)
-		return
-	}
-	w.Header().Set("Content-Type", "application/json")
-	_, err = w.Write(jsonDesc)
-	if err != nil {
-		log.Println("An error occurred while sending session description", err)
-	}
-
-	// Increment monitoring
-	monitoring.WebSessions.Inc()
-}
-
-func viewerGetHandler(w http.ResponseWriter, r *http.Request) {
 	// Get stream ID from URL, or from domain name
 	path := r.URL.Path[1:]
 	host := r.Host
@@ -137,27 +81,6 @@ func viewerGetHandler(w http.ResponseWriter, r *http.Request) {
 	monitoring.WebViewerServed.Inc()
 }
 
-// Handle site index and viewer pages
-// POST requests are used to exchange WebRTC session descriptions
-func viewerHandler(w http.ResponseWriter, r *http.Request) {
-	// Validation on path
-	if validPath.FindStringSubmatch(r.URL.Path) == nil {
-		http.NotFound(w, r)
-		log.Printf("Replied not found on %s", r.URL.Path)
-		return
-	}
-
-	// Route depending on HTTP method
-	switch r.Method {
-	case http.MethodGet:
-		viewerGetHandler(w, r)
-	case http.MethodPost:
-		viewerPostHandler(w, r)
-	default:
-		http.Error(w, "Sorry, only GET and POST methods are supported.", http.StatusBadRequest)
-	}
-}
-
 func staticHandler() http.Handler {
 	// Set up static files server
 	staticFs := http.FileServer(pkger.Dir("/web/static"))

web/web.go

@@ -88,6 +88,7 @@ func Serve(s *messaging.Streams, c *Options) {
 	mux := http.NewServeMux()
 	mux.HandleFunc("/", viewerHandler)
 	mux.Handle("/static/", staticHandler())
+	mux.HandleFunc("/_ws/", websocketHandler)
 	mux.HandleFunc("/_stats/", statisticsHandler)
 	log.Printf("HTTP server listening on %s", cfg.ListenAddress)
 	log.Fatal(http.ListenAndServe(cfg.ListenAddress, mux))

web/websocket_handler.go

@@ -0,0 +1,66 @@
+package web
+
+import (
+	"log"
+	"net/http"
+
+	"github.com/gorilla/websocket"
+	"gitlab.crans.org/nounous/ghostream/stream/webrtc"
+)
+
+var upgrader = websocket.Upgrader{
+	ReadBufferSize:  1024,
+	WriteBufferSize: 1024,
+}
+
+// clientDescription is sent by new client
+type clientDescription struct {
+	webRtcSdp webrtc.SessionDescription
+	stream    string
+	quality   string
+}
+
+// websocketHandler exchanges WebRTC SDP and viewer count
+func websocketHandler(w http.ResponseWriter, r *http.Request) {
+	// Upgrade client connection to WebSocket
+	conn, err := upgrader.Upgrade(w, r, nil)
+	if err != nil {
+		log.Printf("Failed to upgrade client to websocket: %s", err)
+		return
+	}
+
+	for {
+		// Get client description
+		c := &clientDescription{}
+		err = conn.ReadJSON(c)
+		if err != nil {
+			log.Printf("Failed to receive client description: %s", err)
+			return
+		}
+
+		// Get requested stream
+		stream, err := streams.Get(c.stream)
+		if err != nil {
+			log.Printf("Stream not found: %s", c.stream)
+			return
+		}
+
+		// Get requested quality
+		q, err := stream.GetQuality(c.quality)
+		if err != nil {
+			log.Printf("Quality not found: %s", c.quality)
+			return
+		}
+
+		// Exchange session descriptions with WebRTC stream server
+		// FIXME: Add trickle ICE support
+		q.WebRtcRemoteSdp <- c.webRtcSdp
+		localDescription := <-q.WebRtcLocalSdp
+
+		// Send new local description
+		if err := conn.WriteJSON(localDescription); err != nil {
+			log.Println(err)
+			return
+		}
+	}
+}