31:T27ba,// Adapted From: https://codelabs.developers.google.com/codelabs/webrtc-web/#4 { //cell start init(); return html`⏎ Click cell to see Peer to Peer WebRTC`; function init(){ // Set up media stream constant and parameters. // In this codelab, you will be streaming video only: "video: true". // Audio will not be streamed because it is set to "audio: false" by default. const mediaStreamConstraints = { video: true, width: 200, height: 200 }; // Set up to exchange only video. const offerOptions = { offerToReceiveVideo: 1, }; // Define initial start time of the call (defined as connection between peers). let startTime = null; // Define peer connections, streams and video elements. //const localVideo = document.getElementById('localVideo'); //const remoteVideo = document.getElementById('remoteVideo'); const localVideo = appRTC.querySelector('#localVideo'); const remoteVideo = appRTC.querySelector('#remoteVideo'); let localStream; let remoteStream; let localPeerConnection; let remotePeerConnection; // Define MediaStreams callbacks. // Sets the MediaStream as the video element src. function gotLocalMediaStream(mediaStream) { localVideo.srcObject = mediaStream; localStream = mediaStream; trace('Received local stream.'); callButton.disabled = false; // Enable call button. } // Handles error by logging a message to the console. function handleLocalMediaStreamError(error) { trace(`navigator.getUserMedia error: ${error.toString()}.`); } // Handles remote MediaStream success by adding it as the remoteVideo src. function gotRemoteMediaStream(event) { const mediaStream = event.stream; remoteVideo.srcObject = mediaStream; remoteStream = mediaStream; trace('Remote peer connection received remote stream.'); } // Add behavior for video streams. // Logs a message with the id and size of a video element. function logVideoLoaded(event) { const video = event.target; trace(`${video.id} videoWidth: ${video.videoWidth}px, ` + `videoHeight: ${video.videoHeight}px.`); } // Logs a message with the id and size of a video element. // This event is fired when video begins streaming. function logResizedVideo(event) { logVideoLoaded(event); if (startTime) { const elapsedTime = window.performance.now() - startTime; startTime = null; trace(`Setup time: ${elapsedTime.toFixed(3)}ms.`); } } localVideo.addEventListener('loadedmetadata', logVideoLoaded); remoteVideo.addEventListener('loadedmetadata', logVideoLoaded); remoteVideo.addEventListener('onresize', logResizedVideo); // Define RTC peer connection behavior. // Connects with new peer candidate. function handleConnection(event) { const peerConnection = event.target; const iceCandidate = event.candidate; if (iceCandidate) { const newIceCandidate = new RTCIceCandidate(iceCandidate); const otherPeer = getOtherPeer(peerConnection); otherPeer.addIceCandidate(newIceCandidate) .then(() => { handleConnectionSuccess(peerConnection); }).catch((error) => { handleConnectionFailure(peerConnection, error); }); trace(`${getPeerName(peerConnection)} ICE candidate:\n` + `${event.candidate.candidate}.`); } } // Logs that the connection succeeded. function handleConnectionSuccess(peerConnection) { trace(`${getPeerName(peerConnection)} addIceCandidate success.`); }; // Logs that the connection failed. function handleConnectionFailure(peerConnection, error) { trace(`${getPeerName(peerConnection)} failed to add ICE Candidate:\n`+ `${error.toString()}.`); } // Logs changes to the connection state. function handleConnectionChange(event) { const peerConnection = event.target; console.log('ICE state change event: ', event); trace(`${getPeerName(peerConnection)} ICE state: ` + `${peerConnection.iceConnectionState}.`); } // Logs error when setting session description fails. function setSessionDescriptionError(error) { trace(`Failed to create session description: ${error.toString()}.`); } // Logs success when setting session description. function setDescriptionSuccess(peerConnection, functionName) { const peerName = getPeerName(peerConnection); trace(`${peerName} ${functionName} complete.`); } // Logs success when localDescription is set. function setLocalDescriptionSuccess(peerConnection) { setDescriptionSuccess(peerConnection, 'setLocalDescription'); } // Logs success when remoteDescription is set. function setRemoteDescriptionSuccess(peerConnection) { setDescriptionSuccess(peerConnection, 'setRemoteDescription'); } // Logs offer creation and sets peer connection session descriptions. function createdOffer(description) { trace(`Offer from localPeerConnection:\n${description.sdp}`); trace('localPeerConnection setLocalDescription start.'); localPeerConnection.setLocalDescription(description) .then(() => { setLocalDescriptionSuccess(localPeerConnection); }).catch(setSessionDescriptionError); trace('remotePeerConnection setRemoteDescription start.'); remotePeerConnection.setRemoteDescription(description) .then(() => { setRemoteDescriptionSuccess(remotePeerConnection); }).catch(setSessionDescriptionError); trace('remotePeerConnection createAnswer start.'); remotePeerConnection.createAnswer() .then(createdAnswer) .catch(setSessionDescriptionError); } // Logs answer to offer creation and sets peer connection session descriptions. function createdAnswer(description) { trace(`Answer from remotePeerConnection:\n${description.sdp}.`); trace('remotePeerConnection setLocalDescription start.'); remotePeerConnection.setLocalDescription(description) .then(() => { setLocalDescriptionSuccess(remotePeerConnection); }).catch(setSessionDescriptionError); trace('localPeerConnection setRemoteDescription start.'); localPeerConnection.setRemoteDescription(description) .then(() => { setRemoteDescriptionSuccess(localPeerConnection); }).catch(setSessionDescriptionError); } // Define and add behavior to buttons. // Define action buttons. /* const startButton = document.getElementById('startButton'); const callButton = document.getElementById('callButton'); const hangupButton = document.getElementById('hangupButton'); */ const startButton = appRTC.querySelector('#startButton'); const callButton = appRTC.querySelector('#callButton'); const hangupButton = appRTC.querySelector('#hangupButton'); // Set up initial action buttons status: disable call and hangup. callButton.disabled = true; hangupButton.disabled = true; // Handles start button action: creates local MediaStream. function startAction() { startButton.disabled = true; navigator.mediaDevices.getUserMedia(mediaStreamConstraints) .then(gotLocalMediaStream).catch(handleLocalMediaStreamError); trace('Requesting local stream.'); } // Handles call button action: creates peer connection. function callAction() { callButton.disabled = true; hangupButton.disabled = false; trace('Starting call.'); startTime = window.performance.now(); // Get local media stream tracks. const videoTracks = localStream.getVideoTracks(); const audioTracks = localStream.getAudioTracks(); if (videoTracks.length > 0) { trace(`Using video device: ${videoTracks[0].label}.`); } if (audioTracks.length > 0) { trace(`Using audio device: ${audioTracks[0].label}.`); } const servers = null; // Allows for RTC server configuration. // Create peer connections and add behavior. localPeerConnection = new RTCPeerConnection(servers); trace('Created local peer connection object localPeerConnection.'); localPeerConnection.addEventListener('icecandidate', handleConnection); localPeerConnection.addEventListener( 'iceconnectionstatechange', handleConnectionChange); remotePeerConnection = new RTCPeerConnection(servers); trace('Created remote peer connection object remotePeerConnection.'); remotePeerConnection.addEventListener('icecandidate', handleConnection); remotePeerConnection.addEventListener( 'iceconnectionstatechange', handleConnectionChange); remotePeerConnection.addEventListener('addstream', gotRemoteMediaStream); // Add local stream to connection and create offer to connect. localPeerConnection.addStream(localStream); trace('Added local stream to localPeerConnection.'); trace('localPeerConnection createOffer start.'); localPeerConnection.createOffer(offerOptions) .then(createdOffer).catch(setSessionDescriptionError); } // Handles hangup action: ends up call, closes connections and resets peers. function hangupAction() { localPeerConnection.close(); remotePeerConnection.close(); localPeerConnection = null; remotePeerConnection = null; hangupButton.disabled = true; callButton.disabled = false; trace('Ending call.'); } // Add click event handlers for buttons. startButton.addEventListener('click', startAction); callButton.addEventListener('click', callAction); hangupButton.addEventListener('click', hangupAction); // Define helper functions. // Gets the "other" peer connection. function getOtherPeer(peerConnection) { return (peerConnection === localPeerConnection) ? remotePeerConnection : localPeerConnection; } // Gets the name of a certain peer connection. function getPeerName(peerConnection) { return (peerConnection === localPeerConnection) ? 'localPeerConnection' : 'remotePeerConnection'; } // Logs an action (text) and the time when it happened on the console. function trace(text) { text = text.trim(); const now = (window.performance.now() / 1000).toFixed(3); console.log(now, text); } } //init } //cell end 32:[] 2f:{"title":"Hello RTCPeerConnection","cells":[{"id":0,"value":"md`# Hello RTCPeerConnection\nAn Observable implementation of Google's [*Stream video with RTCPeerConnection*](https://codelabs.developers.google.com/codelabs/webrtc-web/#4) code lab`","pinned":false,"hidden":false,"mode":"ojs"},{"id":74,"value":"appRTC = html`\n\n\n\n

\n\n \n \n \n \n \n \n \n

Local	Remote

\n \n \n \n

\n`","pinned":false,"hidden":false,"mode":"ojs"},{"id":222,"value":"md`## Code:`","pinned":false,"hidden":false,"mode":"ojs"},{"id":182,"value":"$31","pinned":false,"hidden":false,"mode":"ojs"},{"id":276,"value":"//As per lab's recommendation:\nrequire(\"https://webrtc.github.io/adapter/adapter-latest.js\")","pinned":false,"hidden":false,"mode":"ojs"}],"files":"$W32","stdlib":"1","titling":"auto"}