Move server to server-webrtc.

To make room for the WebSocket server we're actually going to use as a
primary server. Move server-webrtc docs to server-webrtc/README.md.

server-webrtc/http.go

@@ -0,0 +1,67 @@
+// An HTTP-based signaling channel for the WebRTC server. It imitates the
+// broker as seen by clients, but it doesn't connect them to an
+// intermediate WebRTC proxy, rather connects them directly to this WebRTC
+// server. This code should be deleted when we have proxies in place.
+
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+
+	"github.com/keroserene/go-webrtc"
+)
+
+type httpHandler struct {
+	config *webrtc.Configuration
+}
+
+func (h *httpHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	switch req.Method {
+	case "GET":
+		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte(`HTTP signaling channel
+
+Send a POST request containing an SDP offer. The response will
+contain an SDP answer.
+`))
+		return
+	case "POST":
+		break
+	default:
+		http.Error(w, "Bad request.", http.StatusBadRequest)
+		return
+	}
+
+	// POST handling begins here.
+	body, err := ioutil.ReadAll(http.MaxBytesReader(w, req.Body, 100000))
+	if err != nil {
+		http.Error(w, "Bad request.", http.StatusBadRequest)
+		return
+	}
+	offer := webrtc.DeserializeSessionDescription(string(body))
+	if offer == nil {
+		http.Error(w, "Bad request.", http.StatusBadRequest)
+		return
+	}
+
+	pc, err := makePeerConnectionFromOffer(offer, h.config)
+	if err != nil {
+		http.Error(w, fmt.Sprintf("Cannot create offer: %s", err), http.StatusInternalServerError)
+		return
+	}
+
+	log.Println("answering HTTP POST")
+
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte(pc.LocalDescription().Serialize()))
+}
+
+func receiveSignalsHTTP(addr string, config *webrtc.Configuration) error {
+	http.Handle("/", &httpHandler{config})
+	log.Printf("listening HTTP on %s", addr)
+	return http.ListenAndServe(addr, nil)
+}