upstream-pion-webrtc/examples/warp/index.html

<!DOCTYPE html>
<html>
  <!--
		SPDX-FileCopyrightText: 2026 The Pion community <https://pion.ly>
		SPDX-License-Identifier: MIT
	-->
<head>
  <meta charset="utf-8">
  <title>WARP: Faster WebRTC with SNAP and SPED</title>
</head>
<body>
  <h2>📡 WebRTC DataChannel Test</h2>
  <div>
    <label><input type="checkbox" id="dtlsRole" />Act as DTLS client</label>
    <button id="startBtn" onclick="start()">Start</button>
  </div>
  <input id="msg" placeholder="Message">
  <button id="sendBtn" disabled onclick="sendMsg()">Send</button>
  <pre id="log"></pre>

  <script>
    const pc = new RTCPeerConnection();
    const channel = pc.createDataChannel("chat");

    pc.onconnectionstatechange = async () => {
        log(`🔄 Connection state: ${pc.connectionState}`);
        if (pc.connectionState === 'connected') {
            const stats = await pc.getStats();
            const transport = [...stats.values()].find(o => o.type === 'transport');
            if (transport) {
                log(`DTLS role: ${transport.dtlsRole}`);
                const pair = stats.get(transport.selectedCandidatePairId);
                if (pair) {
                    log(`RTT: ${pair.totalRoundTripTime / pair.responsesReceived}`);
                }
            }
        }
    }
    pc.oniceconnectionstatechange = () => log(`🧊 ICE state: ${pc.iceConnectionState}`);
    pc.onsignalingstatechange = () => log(`📞 Signaling state: ${pc.signalingState}`);

    channel.onopen = () => {
      log("✅ DataChannel opened");
      document.getElementById("sendBtn").disabled = false;
    }
    channel.onmessage = e => log(`📩 Server: ${e.data}`);

    pc.onicecandidate = event => {
      if(event.candidate){
        fetch("/candidate", {
          method: "POST",
          headers: {"Content-Type": "application/json"},
          body: JSON.stringify(event.candidate),
        });
      }
    };
    pc.ondatachannel = event => {
        log("Server opened a channel", event.channel.name)
        event.channel.onmessage = (ev) => {
          log(`Server sent: ${ev.data}`)
        }
    };

    async function start(){
      document.getElementById("startBtn").disabled = true;
      document.getElementById("dtlsRole").disabled = true;
      try {
        await pc.setLocalDescription();
        const offer = pc.localDescription;
        if (offer.sdp.indexOf("\na=sctp-init:") !== -1) {
          log("✅ sctp-init found in offer, SNAP is supported");
        }

        const sdp = document.getElementById("dtlsRole").checked
          ? offer.sdp.replace("actpass", "active")
          : offer.sdp;
        // TODO: parameters to disable SPED/SNAP?
        const res = await fetch("/offer", {
          method: "POST",
          headers: {"Content-Type": "application/json"},
          body: JSON.stringify({type: "offer", sdp}),
        })

        if (!res.ok) {
          throw new Error(`HTTP ${res.status}: ${res.statusText}`);
        }

        const answer = await res.json();
        if (answer.sdp.indexOf("\na=sctp-init:") !== -1) {
          log("✅ sctp-init found in answer, SNAP is supported");
        }
        await pc.setRemoteDescription(answer);

      } catch (err) {
        log(`❌ Connection failed: ${err.message}`);
        console.error("Connection error:", err);
      }
    }

    function sendMsg(){
      const msg = document.getElementById("msg").value;

      if (msg.trim()) {
        channel.send(msg);
        log(`You: ${msg}`);
        document.getElementById("msg").value = "";
      }
    }

    function log(msg){
      document.getElementById("log").textContent+=msg+"\n";
    }


  </script>
</body>
</html>