主要架构
1 peerA 向着 服务端发送join信令
// 获取本地流 promise 的then
function openLocalStream(stream) {
console.log('Open local stream');
doJoin(roomId);
localVideo.srcObject = stream;
localStream = stream;
}
function doJoin(roomId) {
var jsonMsg = {
'cmd': 'join',
'roomId': roomId,
'uid': localUserId,
};
var message = JSON.stringify(jsonMsg);
//通过封装好的 sendmessage发送
zeroRTCEngine.sendMessage(message);
console.info("doJoin message: " + message);
}
2 peerB 向着 服务端发送join信令
// 获取本地流 promise 的then
function openLocalStream(stream) {
console.log('Open local stream');
doJoin(roomId);
localVideo.srcObject = stream;
localStream = stream;
}
function doJoin(roomId) {
var jsonMsg = {
'cmd': 'join',
'roomId': roomId,
'uid': localUserId,
};
var message = JSON.stringify(jsonMsg);
zeroRTCEngine.sendMessage(message);
console.info("doJoin message: " + message);
}
3 - 4 信令服务器向着双方返回 new-peer 和resp-join 信令
服务器信令处理
// join 主动加入房间
// leave 主动离开房间
// new-peer 有人加入房间，通知已经在房间的人
// peer-leave 有人离开房间，通知已经在房间的人
// offer 发送offer给对端peer
// answer发送offer给对端peer
// candidate 发送candidate给对端peer
const SIGNAL_TYPE_JOIN = "join";
const SIGNAL_TYPE_RESP_JOIN = "resp-join"; // 告知加入者对方是谁
const SIGNAL_TYPE_LEAVE = "leave";
const SIGNAL_TYPE_NEW_PEER = "new-peer";
const SIGNAL_TYPE_PEER_LEAVE = "peer-leave";
const SIGNAL_TYPE_OFFER = "offer";
const SIGNAL_TYPE_ANSWER = "answer";
const SIGNAL_TYPE_CANDIDATE = "candidate";
服务器对于信令处理的整体
var server = ws.createServer(function(conn){
console.log("创建一个新的连接--------")
conn.client = null; // 对应的客户端信息
// conn.sendText("我收到你的连接了....");
conn.on("text", function(str) {
// console.info("recv msg:" + str);
var jsonMsg = JSON.parse(str);
switch (jsonMsg.cmd) {
case SIGNAL_TYPE_JOIN:
conn.client = handleJoin(jsonMsg, conn);
break;
case SIGNAL_TYPE_LEAVE:
handleLeave(jsonMsg);
break;
case SIGNAL_TYPE_OFFER:
handleOffer(jsonMsg);
break;
case SIGNAL_TYPE_ANSWER:
handleAnswer(jsonMsg);
break;
case SIGNAL_TYPE_CANDIDATE:
handleCandidate(jsonMsg);
break;
}
});
处理Join 信令
function handleJoin(message, conn) {
var roomId = message.roomId;
var uid = message.uid;
console.info("uid: " + uid + "try to join room " + roomId);
var roomMap = roomTableMap.get(roomId);
if (roomMap == null) {
roomMap = new ZeroRTCMap();
roomTableMap.put(roomId, roomMap);
}
if(roomMap.size() >= 2) {
console.error("roomId:" + roomId + " 已经有两人存在，请使用其他房间");
// 加信令通知客户端，房间已满
也可以 设计一个full 信令比如:
var jsonMsg = {
'cmd': SIGNAL_TYPE_PEER_FULL,
'remoteUid': uid
};
msg = JSON.stringify(jsonMsg);
然后发送 console.info("room_full: " + msg);
conn.sendText(msg);
return null;
}
var client = new Client(uid, conn, roomId);
roomMap.put(uid, client);
if(roomMap.size() > 1) {
// 房间里面已经有人了，加上新进来的人，那就是>=2了，所以要通知对方
var clients = roomMap.getEntrys();
for(var i in clients) {
var remoteUid = clients[i].key;
if (remoteUid != uid) {
var jsonMsg = {
//通知第一个进房间的人 有人进来了
'cmd': SIGNAL_TYPE_NEW_PEER,
'remoteUid': uid
};
var msg = JSON.stringify(jsonMsg);
var remoteClient =roomMap.get(remoteUid);
console.info("new-peer: " + msg);
remoteClient.conn.sendText(msg);
jsonMsg = {
//返回 后进房间的这个人 已经进来房间人的id
'cmd':SIGNAL_TYPE_RESP_JOIN,
'remoteUid': remoteUid
};
msg = JSON.stringify(jsonMsg);
console.info("resp-join: " + msg);
conn.sendText(msg);
}
}
}
return client;
}
5 A收到new-peer 信令后 B 收到resp——join信令以后
B收到以后
function handleResponseJoin(message) {
console.info("handleResponseJoin, remoteUid: " + message.remoteUid);
remoteUserId = message.remoteUid;
}
A收到以后
function handleRemoteNewPeer(message) {
console.info("handleRemoteNewPeer, remoteUid: " + message.remoteUid);
保存远端id
remoteUserId = message.remoteUid;
为双方交换sdp做准备
doOffer();
}
6 A -> offer->信令服务器
当A收到B加入房间后 就开始为了双方通讯做准备（具体函数doffer）
doffer
function doOffer() {
// 创建RTCPeerConnection
if (pc == null) {
createPeerConnection();
}
pc.createOffer().then(createOfferAndSendMessage).catch(handleCreateOfferError);
}
1 如果没有rtcPeerConnection创建 具体参数前面说了
function createPeerConnection() {
var defaultConfiguration = {
bundlePolicy: "max-bundle",
rtcpMuxPolicy: "require",
iceTransportPolicy:"relay",//relay 或者 all
// 修改ice数组测试效果，需要进行封装
iceServers: [
{
"urls": [
"turn:公网ip/域名?transport=udp",
"turn:公网ip/域名?transport=tcp" // 可以插入多个进行备选
],
"username": "test", coturn 设置的
"credential": "123456"
},
{
"urls": [
"stun:公网ip/域名"
]
}
]
};
pc = new RTCPeerConnection(defaultConfiguration);
pc.onicecandidate = handleIceCandidate; //回调Candidate 函数
pc.ontrack = handleRemoteStreamAdd; //回调处理远端流的函数
pc.onconnectionstatechange = handleConnectionStateChange;
pc.oniceconnectionstatechange = handleIceConnectionStateChange
localStream.getTracks().forEach((track) => pc.addTrack(track, localStream)); // 给video本地的绑定本地流 中的对应轨 WebRtc不同于ffmpeg一流可以多轨 一轨== 一个音视频ffmpeg流那种
}
2 创建好了 就发送创建本地offer success然后调用 createOfferAndSendMessage 失败就是xxx 上面有
session 就是 pc.createOffer() 返回值了
function createOfferAndSendMessage(session) {
pc.setLocalDescription(session)
.then(function () {
var jsonMsg = {
'cmd': 'offer',
'roomId': roomId,
'uid': localUserId,
'remoteUid': remoteUserId,
'msg': JSON.stringify(session)
};
var message = JSON.stringify(jsonMsg);
zeroRTCEngine.sendMessage(message);
// console.info("send offer message: " + message);
console.info("send offer message");
})
.catch(function (error) {
console.error("offer setLocalDescription failed: " + error);
});
}
7 服务器收到A的offer
服务直接转发了 所以信令的cmd 没变还是 offer
function handleOffer(message) {
var roomId = message.roomId;
var uid = message.uid;
var remoteUid = message.remoteUid;
console.info("handleOffer uid: " + uid + "transfer offer to remoteUid" + remoteUid);
// 找房间
var roomMap = roomTableMap.get(roomId);
if (roomMap == null) {
console.error("handleOffer can't find then roomId " + roomId);
return;
}
// 找人
if(roomMap.get(uid) == null) {
console.error("handleOffer can't find then uid " + uid);
return;
}
// 找到以后发送
var remoteClient = roomMap.get(remoteUid);
if(remoteClient) {
var msg = JSON.stringify(message);
remoteClient.conn.sendText(msg);
} else {
console.error("can't find remoteUid： " + remoteUid);
}
}
8 信令服务器发送offer 给 B
逻辑同上 但是这里 先 pc.setRemoteDescription(desc); 罢了
然后就说doAnswer();
function handleRemoteOffer(message) {
console.info("handleRemoteOffer");
if(pc == null) {
createPeerConnection();
}
var desc = JSON.parse(message.msg);
pc.setRemoteDescription(desc);
doAnswer();
}
doAnswer() 逻辑同上doffer
function doAnswer() {
pc.createAnswer().then(createAnswerAndSendMessage).catch(handleCreateAnswerError);
}
function createAnswerAndSendMessage(session) {
pc.setLocalDescription(session)
.then(function () {
var jsonMsg = {
'cmd': 'answer',
'roomId': roomId,
'uid': localUserId,
'remoteUid': remoteUserId,
'msg': JSON.stringify(session)
};
var message = JSON.stringify(jsonMsg);
zeroRTCEngine.sendMessage(message);
// console.info("send answer message: " + message);
console.info("send answer message");
})
.catch(function (error) {
console.error("answer setLocalDescription failed: " + error);
});
}
9-10 服务器接收answer 并且转发answer 逻辑同上offer
服务器接收answer
function handleAnswer(message) {
var roomId = message.roomId;
var uid = message.uid;
var remoteUid = message.remoteUid;
console.info("handleAnswer uid: " + uid + "transfer answer to remoteUid" + remoteUid);
var roomMap = roomTableMap.get(roomId);
if (roomMap == null) {
console.error("handleAnswer can't find then roomId " + roomId);
return;
}
if(roomMap.get(uid) == null) {
console.error("handleAnswer can't find then uid " + uid);
return;
}
var remoteClient = roomMap.get(remoteUid);
if(remoteClient) {
var msg = JSON.stringify(message);
remoteClient.conn.sendText(msg);
} else {
console.error("can't find remoteUid： " + remoteUid);
}
}
A收到服端发送过的Answer
function handleRemoteAnswer(message) {
console.info("handleRemoteAnswer");
var desc = JSON.parse(message.msg);
pc.setRemoteDescription(desc);
}
现在会触发创建RTCPeerConnection 时候绑定的回调函数（ontrack也触发了不过没有数据传输过来不显示罢了）
10 A 向服务器传递 condidate(通过初始化RTCPeerconnection 对于Conturn服务器配置 内部通过ice request 得到了自己的地址 ) 11 信令服务器转发向B
A 向服务器传递 condidate
function handleIceCandidate(event) {
console.info("handleIceCandidate");
if (event.candidate) {
var jsonMsg = {
'cmd': 'candidate',
'roomId': roomId,
'uid': localUserId,
'remoteUid': remoteUserId,
'msg': JSON.stringify(event.candidate)
};
var message = JSON.stringify(jsonMsg);
zeroRTCEngine.sendMessage(message);
// console.info("handleIceCandidate message: " + message);
console.info("send candidate message");
} else {
console.warn("End of candidates");
}
}
信令服务器转发A的condidate向B 逻辑同offer
function handleAnswer(message) {
var roomId = message.roomId;
var uid = message.uid;
var remoteUid = message.remoteUid;
console.info("handleAnswer uid: " + uid + "transfer answer to remoteUid" + remoteUid);
var roomMap = roomTableMap.get(roomId);
if (roomMap == null) {
console.error("handleAnswer can't find then roomId " + roomId);
return;
}
if(roomMap.get(uid) == null) {
console.error("handleAnswer can't find then uid " + uid);
return;
}
var remoteClient = roomMap.get(remoteUid);
if(remoteClient) {
var msg = JSON.stringify(message);
remoteClient.conn.sendText(msg);
} else {
console.error("can't find remoteUid： " + remoteUid);
}
}
function handleCandidate(message) {
var roomId = message.roomId;
var uid = message.uid;
var remoteUid = message.remoteUid;
console.info("handleCandidate uid: " + uid + "transfer candidate to remoteUid" + remoteUid);
var roomMap = roomTableMap.get(roomId);
if (roomMap == null) {
console.error("handleCandidate can't find then roomId " + roomId);
return;
}
if(roomMap.get(uid) == null) {
console.error("handleCandidate can't find then uid " + uid);
return;
}
var remoteClient = roomMap.get(remoteUid);
if(remoteClient) {
var msg = JSON.stringify(message);
remoteClient.conn.sendText(msg);
} else {
console.error("can't find remoteUid： " + remoteUid);
}
}
12 - 13 B接收服务器转发到A的condidate B向着信令服务器发送A的condidate
pc.addIceCandidate(candidate) 通过该函数保存对端 condidate 信息 然后触发handleIceCandidate（） 发送数据向服务器
function handleRemoteCandidate(message) {
console.info("handleRemoteCandidate");
var candidate = JSON.parse(message.msg);
pc.addIceCandidate(candidate).catch(e => {
console.error("addIceCandidate failed:" + e.name);
});
}
function handleIceCandidate(event) {
console.info("handleIceCandidate");
if (event.candidate) {
var jsonMsg = {
'cmd': 'candidate',
'roomId': roomId,
'uid': localUserId,
'remoteUid': remoteUserId,
'msg': JSON.stringify(event.candidate)
};
var message = JSON.stringify(jsonMsg);
zeroRTCEngine.sendMessage(message);
// console.info("handleIceCandidate message: " + message);
console.info("send candidate message");
} else {
console.warn("End of candidates");
}
}
14 -15 A收到B的condidate 后续处理都是一样的 然后就condidate配对 一般3对 成功一个就开始音视频通话了（如果P2P能成功则进行P2P通话，如果P2P不成功则进行中继转发通话）
16 leave处理
客户端
function handleRemotePeerLeave(message) {
console.info("handleRemotePeerLeave, remoteUid: " + message.remoteUid);
remoteVideo.srcObject = null;
if(pc != null) {
pc.close();
pc = null;
}
}
服务端
function handleLeave(message) {
var roomId = message.roomId;
var uid = message.uid;
console.info("uid: " + uid + "leave room " + roomId);
var roomMap = roomTableMap.get(roomId);
if (roomMap == null) {
console.error("handleLeave can't find then roomId " + roomId);
return;
}
roomMap.remove(uid); // 删除发送者
if(roomMap.size() >= 1) {
var clients = roomMap.getEntrys();
for(var i in clients) {
var jsonMsg = {
'cmd': 'peer-leave',
'remoteUid': uid // 谁离开就填写谁
};
var msg = JSON.stringify(jsonMsg);
var remoteUid = clients[i].key;
var remoteClient = roomMap.get(remoteUid);
if(remoteClient) {
console.info("notify peer:" + remoteClient.uid + ", uid:" + uid + " leave");
remoteClient.conn.sendText(msg);
}
}
}
}
function handleForceLeave(client) {
var roomId = client.roomId;
var uid = client.uid;
// 1. 先查找房间号
var roomMap = roomTableMap.get(roomId);
if (roomMap == null) {
console.warn("handleForceLeave can't find then roomId " + roomId);
return;
}
// 2. 判别uid是否在房间
if (!roomMap.contains(uid)) {
console.info("uid: " + uid +" have leave roomId " + roomId);
return;
}
// 3.走到这一步，说明客户端没有正常离开，所以我们要执行离开程序
console.info("uid: " + uid + " force leave room " + roomId);
roomMap.remove(uid); // 删除发送者
if(roomMap.size() >= 1) {
var clients = roomMap.getEntrys();
for(var i in clients) {
var jsonMsg = {
'cmd': 'peer-leave',
'remoteUid': uid // 谁离开就填写谁
};
var msg = JSON.stringify(jsonMsg);
var remoteUid = clients[i].key;
var remoteClient = roomMap.get(remoteUid);
if(remoteClient) {
console.info("notify peer:" + remoteClient.uid + ", uid:" + uid + " leave");
remoteClient.conn.sendText(msg);
}
}
}
}