WebRTC 服務器之Janus視頻會議插件信令交互

?1.基礎知識回顧

WebRTC 服務器之Janus概述和環境搭建-CSDN博客

WebRTC 服務器之Janus架構分析-CSDN博客

2.插件使用流程

我們要使?janus的功能時，通常要執?以下操作：

1. 在你的??引入 Janus.js 庫，即是包含janus.js；

<!-- 網頁頭部或 body 底部引入 -->
<script src="https://your-cdn-path/janus.js"></script>

2. 初始化 Janus 庫，并傳遞其依賴項(依賴項可選)；

Janus.init({debug: true,    // 開啟調試日志dependencies: {// 可選依賴（如 adapter.js 用于跨瀏覽器兼容）adapter: adapter},callback: function() {console.log("Janus 庫初始化完成");// 初始化完成后連接服務器connectToJanusServer();}
});

3. 連接服務器 & 創建會話?連接到janus server并創建create?個會話session；

let janusSession;function connectToJanusServer() {const serverUrl = "wss://your-janus-server:8989/janus";new Janus({server: serverUrl,success: function(session) {janusSession = session;console.log("會話創建成功:", session.getId());// 創建插件句柄（例如加入視頻房間）attachToVideoRoomPlugin();},error: function(error) {console.error("連接失敗:", error);}});
}

4. 創建插件句柄 (Handle)?創建?個或多個handle 以attach到插件(plugin)（例如videoroom、videocall等插件）；

let pluginHandle;function attachToVideoRoomPlugin() {janusSession.attach({plugin: "janus.plugin.videoroom",  // 插件名稱success: function(handle) {pluginHandle = handle;console.log("成功附加到插件，句柄 ID:", handle.getId());// 發送加入房間請求joinVideoRoom();},error: function(error) {console.error("附加插件失敗:", error);}});
}

5. 信令交互示例 - 加入視頻房間?與創建交互（發送/接收消息，協商PeerConnection）；

function joinVideoRoom() {const joinMsg = {request: "join",room: 1234,       // 房間 IDptype: "publisher",display: "用戶1"};pluginHandle.send({ message: joinMsg });
}// 處理服務器事件（如房間通知）
pluginHandle.on("message", (msg, jsep) => {console.log("收到服務器消息:", msg);if (msg["videoroom"] === "joined") {console.log("成功加入房間!");// 處理媒體協商（如創建 Offer）startWebRTCNegotiation();}
});

6. ?WebRTC 協商流程?

function startWebRTCNegotiation() {// 創建媒體配置const mediaConfig = {audio: true,video: true,data: true};// 準備 PeerConnectionpluginHandle.createOffer({media: mediaConfig,success: function(sdp) {// 發送 SDP OfferpluginHandle.sendSDP(sdp);},error: function(error) {console.error("創建 Offer 失敗:", error);}});
}// 處理 ICE Candidate
pluginHandle.on("ice", (candidate) => {// 發送候選到服務器pluginHandle.trickle(candidate);
});

7. 最后關閉所有的handles并關閉相關的相應的PeerConnections；?消耗destroy會話session。

function cleanup() {// 1. 銷毀插件句柄if (pluginHandle) {pluginHandle.detach();pluginHandle = null;}// 2. 銷毀會話if (janusSession) {janusSession.destroy();janusSession = null;}
}// 頁面關閉時觸發清理
window.onbeforeunload = cleanup;

?完整流程總結

初始化
Janus.init({ debug: true, callback: createJanusSession });
會話與插件
創建會話 (createSession) → 創建插件句柄 (createHandle) → 注冊事件監聽 (eventHandler).?
信令交互
發送消息 (sendMessage) 加入房間 → 接收服務器事件 (handleEvent).
WebRTC 協商
創建 Offer (createOffer) → 發送 SDP (sendSDP) → 接收 Answer → 創建 Answer (createAnswer).
收發av數據
資源釋放
銷毀句柄 (destroyHandle) → 銷毀會話 (destroySession).

2.1 協議基本類型

"janus"后?的字符串代表消息的類型，主要有：

create：創建?個Janus會話命令；
attach：attach?個插件到Janus會話命令；
success：?個命令的成功結果；
error：?個命令的失敗結果；
ack：?個命令的ack，因為不能直接返回結果，先回ack，后續的結果通過event返回；
event：推送給客戶端的異步事件，主要由插件發出，這些事件需要插件來??定義；
message：客戶端發給插件的消息，message和event就構成了應?協議；
trickle：客戶端發送的candidate，會傳遞給ICE句柄；
keepalive：客戶端發送的?跳；
webrtcup：ICE成功建?通道的通知；
media：?頻、視頻媒體的接收通知；
slowlink：鏈路惡化通知；
hangup：掛斷通知；
detached：插件從Janus會話detach的通知，釋放了?個插件句柄。

3.videoroom插件信令交互分析

Janus中所有插件都遵循以下基本數據流程：

客戶端發送create創建一個Janus會話；
Janus回復success返回Janus會話句柄；
客戶端發送attach命令在Janus會話上attach指定插件；
Janus回復success返回插件的句柄；
客戶端給指定的插件發送message進行信令控制；
Janus上的插件發送event通知事件給客戶端；
客戶端收集candidate并通過trickle消息發送給插件綁定的ICE通道；
Janus發送webrtcup通知ICE通道建立；
客戶端發送媒體數據；
Janus發送media消息通知媒體數據的第一次到達；
Janus進行媒體數據轉發。

3.總體邏輯

Janus客戶端->Janus網關: Janus客戶端發送create請求創建會話
- ```
JBJ-WEBSOCKET RECV: {"janus":"create","transaction":"aAMxRfsTsVVQ"}
```

Janus網關–>>Janus客戶端: Janus網關創建會話，并返回會話IDJ

JBJ-WEBSOCKET responses:Sending Janus API response(
{"janus": "success","transaction": "aAMxRfsTsVVQ","data": {"id": 5109637625847547}
}
) to janus.transport.websockets (0x7f5cd400d3c0)

Janus客戶端->Janus網關: 客戶端發送attach命令在Janus會話上attach指定插件；

JBJ-WEBSOCKET RECV: {"janus": "attach","plugin": "janus.plugin.videoroom","opaque_id": "videoroomtest-jIAzP2ZkPUrn","transaction": "2kuM6pzfX4Zh","session_id": 5109637625847547
}

Janus網關–>>Janus客戶端:? Janus回復success返回插件的句柄；


JBJ-WEBSOCKET responses:Sending Janus API response({"janus": "success","session_id": 5109637625847547,"transaction": "2kuM6pzfX4Zh","data": {"id": 6769547295474368}
}) to janus.transport.websockets (0x7f5cd400d3c0)

Janus客戶端->Janus網關:?Janus客戶端給指定插件發送message（Join）

JBJ-WEBSOCKET RECV: {"janus": "message","body": {"request": "join","room": 1234,"ptype": "publisher","display": "321"},"transaction": "11JDzIbsbK91","session_id": 5109637625847547,"handle_id": 6769547295474368
}

JBJ-WEBSOCKET responses:Sending Janus API response({"janus": "ack","session_id": 5109637625847547,"transaction": "11JDzIbsbK91"
}) to janus.transport.websockets (0x7f5cd400d3c0)

Janus網關–>>Janus客戶端: Janus網關處理message，并將結果通過event事件發送給客戶端

Preparing JSON event as a reply
JBJ-video.room.event: [6769547295474368] Sending event is: {"janus": "event","session_id": 5109637625847547,"transaction": "11JDzIbsbK91","sender": 6769547295474368,"plugindata": {"plugin": "janus.plugin.videoroom","data": {"videoroom": "joined","room": 1234,"description": "Demo Room","id": 6538458198168085,"private_id": 1041514801,"publishers": []}}} to transport...
Sending event to janus.transport.websockets (0x7f5cd400d3c0)>> 0 (Success)

Janus客戶端->Janus網關: Janus客戶端給指定插件發送message（Configure & offer）

####################Configure & offer
JBJ-WEBSOCKETRECV: {"janus": "message","body": {"request": "configure","audio": true,"video": true},"transaction": "MHTliRCHqY5y","jsep": {"type": "offer","sdp": "v=0\r\no=- 6239954181818903803 2 IN IP4 127.0.0.1\r\ns=-\r\nt=0 0\r\na=group:BUNDLE 0 1\r\na=extmap-allow-mixed\r\na=msid-semantic: WMS 900722df-7e7a-4951-b1bf-1902cb7fe6e0\r\nm=audio 9 UDP/TLS/RTP/SAVPF 111 63 9 0 8 13 110 126\r\nc=IN IP4 0.0.0.0\r\na=rtcp:9 IN IP4 0.0.0.0\r\na=ice-ufrag:eHT/\r\na=ice-pwd:aAxznBSHiqTXMkZAzJs5xv3B\r\na=ice-options:trickle\r\na=fingerprint:sha-256 75:80:26:F9:EB:47:14:51:61:D3:CD:8B:60:C1:5E:F5:67:53:1E:88:9C:45:53:3B:32:D0:D2:5F:CD:45:63:7F\r\na=setup:actpass\r\na=mid:0\r\na=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level\r\na=extmap:2 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:3 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:4 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=sendonly\r\na=msid:900722df-7e7a-4951-b1bf-1902cb7fe6e0 9718362e-2152-4c32-9e79-da62a8a609c5\r\na=rtcp-mux\r\na=rtcp-rsize\r\na=rtpmap:111 opus/48000/2\r\na=rtcp-fb:111 transport-cc\r\na=fmtp:111 minptime=10;useinbandfec=1\r\na=rtpmap:63 red/48000/2\r\na=fmtp:63 111/111\r\na=rtpmap:9 G722/8000\r\na=rtpmap:0 PCMU/8000\r\na=rtpmap:8 PCMA/8000\r\na=rtpmap:13 CN/8000\r\na=rtpmap:110 telephone-event/48000\r\na=rtpmap:126 telephone-event/8000\r\na=ssrc:2665350871 cname:+3Rknr5a6Axa5msx\r\na=ssrc:2665350871 msid:900722df-7e7a-4951-b1bf-1902cb7fe6e0 9718362e-2152-4c32-9e79-da62a8a609c5\r\nm=video 9 UDP/TLS/RTP/SAVPF 96 97 103 104 107 108 109 114 115 116 117 118 39 40 45 46 98 99 100 101 119 120 123 124 125\r\nc=IN IP4 0.0.0.0\r\na=rtcp:9 IN IP4 0.0.0.0\r\na=ice-ufrag:eHT/\r\na=ice-pwd:aAxznBSHiqTXMkZAzJs5xv3B\r\na=ice-options:trickle\r\na=fingerprint:sha-256 75:80:26:F9:EB:47:14:51:61:D3:CD:8B:60:C1:5E:F5:67:53:1E:88:9C:45:53:3B:32:D0:D2:5F:CD:45:63:7F\r\na=setup:actpass\r\na=mid:1\r\na=extmap:14 urn:ietf:params:rtp-hdrext:toffset\r\na=extmap:2 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time\r\na=extmap:13 urn:3gpp:video-orientation\r\na=extmap:3 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:5 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap:6 http://www.webrtc.org/experiments/rtp-hdrext/video-content-type\r\na=extmap:7 http://www.webrtc.org/experiments/rtp-hdrext/video-timing\r\na=extmap:8 http://www.webrtc.org/experiments/rtp-hdrext/color-space\r\na=extmap:4 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:10 urn:ietf:params:rtp-hdrext:sdes:rtp-stream-id\r\na=extmap:11 urn:ietf:params:rtp-hdrext:sdes:repaired-rtp-stream-id\r\na=sendonly\r\na=msid:900722df-7e7a-4951-b1bf-1902cb7fe6e0 d97d2702-4a0f-4693-8499-71c66f8c03fe\r\na=rtcp-mux\r\na=rtcp-rsize\r\na=rtpmap:96 VP8/90000\r\na=rtcp-fb:96 goog-remb\r\na=rtcp-fb:96 transport-cc\r\na=rtcp-fb:96 ccm fir\r\na=rtcp-fb:96 nack\r\na=rtcp-fb:96 nack pli\r\na=rtpmap:97 rtx/90000\r\na=fmtp:97 apt=96\r\na=rtpmap:103 H264/90000\r\na=rtcp-fb:103 goog-remb\r\na=rtcp-fb:103 transport-cc\r\na=rtcp-fb:103 ccm fir\r\na=rtcp-fb:103 nack\r\na=rtcp-fb:103 nack pli\r\na=fmtp:103 level-asymmetry-allowed=1;packetization-mode=1;profile-level-id=42001f\r\na=rtpmap:104 rtx/90000\r\na=fmtp:104 apt=103\r\na=rtpmap:107 H264/90000\r\na=rtcp-fb:107 goog-remb\r\na=rtcp-fb:107 transport-cc\r\na=rtcp-fb:107 ccm fir\r\na=rtcp-fb:107 nack\r\na=rtcp-fb:107 nack pli\r\na=fmtp:107 level-asymmetry-allowed=1;packetization-mode=0;profile-level-id=42001f\r\na=rtpmap:108 rtx/90000\r\na=fmtp:108 apt=107\r\na=rtpmap:109 H264/90000\r\na=rtcp-fb:109 goog-remb\r\na=rtcp-fb:109 transport-cc\r\na=rtcp-fb:109 ccm fir\r\na=rtcp-fb:109 nack\r\na=rtcp-fb:109 nack pli\r\na=fmtp:109 level-asymmetry-allowed=1;packetization-mode=1;profile-level-id=42e01f\r\na=rtpmap:114 rtx/90000\r\na=fmtp:114 apt=109\r\na=rtpmap:115 H264/90000\r\na=rtcp-fb:115 goog-remb\r\na=rtcp-fb:115 transport-cc\r\na=rtcp-fb:115 ccm fir\r\na=rtcp-fb:115 nack\r\na=rtcp-fb:115 nack pli\r\na=fmtp:115 level-asymmetry-allowed=1;packetization-mode=0;profile-level-id=42e01f\r\na=rtpmap:116 rt
}JBJ-video.room.event: [6769547295474368] Sending event is: {"janus": "event","session_id": 5109637625847547,"transaction": "MHTliRCHqY5y","sender": 6769547295474368,"plugindata": {"plugin": "janus.plugin.videoroom","data": {"videoroom": "event","room": 1234,"configured": "ok","audio_codec": "opus","video_codec": "vp8"}},"jsep": {"type": "answer","sdp": "v=0\r\no=- 6239954181818903803 2 IN IP4 117.72.13.81\r\ns=VideoRoom 1234\r\nt=0 0\r\na=group:BUNDLE 0 1\r\na=msid-semantic: WMS janus\r\nm=audio 9 UDP/TLS/RTP/SAVPF 111\r\nc=IN IP4 117.72.13.81\r\na=recvonly\r\na=mid:0\r\na=rtcp-mux\r\na=ice-ufrag:0pFN\r\na=ice-pwd:wGcEE+9WQLoHULcXGP8KFn\r\na=ice-options:trickle\r\na=fingerprint:sha-256 C7:C1:43:EE:67:07:A0:6D:42:33:6A:CA:4E:EA:95:E0:55:17:03:CB:88:FD:B6:37:AB:1C:7B:85:65:9A:95:C6\r\na=setup:active\r\na=rtpmap:111 opus/48000/2\r\na=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level\r\na=extmap:3 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:4 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=msid:janus janusa0\r\na=ssrc:3338353236 cname:janus\r\na=ssrc:3338353236 msid:janus janusa0\r\na=ssrc:3338353236 mslabel:janus\r\na=ssrc:3338353236 label:janusa0\r\na=candidate:1 1 udp 2013266431 117.72.13.81 53576 typ host\r\na=candidate:2 1 udp 1677722111 117.72.13.81 53576 typ srflx raddr 172.16.0.4 rport 53576\r\na=candidate:3 1 udp 503316991 172.16.0.4 54497 typ relay raddr 172.16.0.4 rport 53576\r\na=end-of-candidates\r\nm=video 9 UDP/TLS/RTP/SAVPF 96 97\r\nc=IN IP4 117.72.13.81\r\na=recvonly\r\na=mid:1\r\na=rtcp-mux\r\na=ice-ufrag:0pFN\r\na=ice-pwd:wGcEE+9WQLoHULcXGP8KFn\r\na=ice-options:trickle\r\na=fingerprint:sha-256 C7:C1:43:EE:67:07:A0:6D:42:33:6A:CA:4E:EA:95:E0:55:17:03:CB:88:FD:B6:37:AB:1C:7B:85:65:9A:95:C6\r\na=setup:active\r\na=rtpmap:96 VP8/90000\r\na=rtcp-fb:96 ccm fir\r\na=rtcp-fb:96 nack\r\na=rtcp-fb:96 nack pli\r\na=rtcp-fb:96 goog-remb\r\na=rtcp-fb:96 transport-cc\r\na=extmap:13 urn:3gpp:video-orientation\r\na=extmap:3 http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01\r\na=extmap:5 http://www.webrtc.org/experiments/rtp-hdrext/playout-delay\r\na=extmap:4 urn:ietf:params:rtp-hdrext:sdes:mid\r\na=extmap:10 urn:ietf:params:rtp-hdrext:sdes:rtp-stream-id\r\na=extmap:11 urn:ietf:params:rtp-hdrext:sdes:repaired-rtp-stream-id\r\na=rtpmap:97 rtx/90000\r\na=fmtp:97 apt=96\r\na=msid:janus janusv0\r\na=ssrc:3467980833 cname:janus\r\na=ssrc:3467980833 msid:janus janusv0\r\na=ssrc:3467980833 mslabel:janus\r\na=ssrc:3467980833 label:janusv0\r\na=ssrc:3074101642 cname:janus\r\na=ssrc:3074101642 msid:janus janusv0\r\na=ssrc:3074101642 mslabel:janus\r\na=ssrc:3074101642 label:janusv0\r\na=candidate:1 1 udp 2013266431 117.72.13.81 53576 typ host\r\na=candidate:2 1 udp 1677722111 117.72.13.81 53576 typ srflx raddr 172.16.0.4 rport 53576\r\na=candidate:3 1 udp 503316991 172.16.0.4 54497 typ relay raddr 172.16.0.4 rport 53576\r\na=end-of-candidates\r\n"}
}#######################trickle
JBJ-WEBSOCKET RECV: {"janus": "trickle","candidate": {"candidate": "candidate:980779705 1 udp 2122260223 192.168.126.1 60475 typ host generation 0 ufrag eHT/ network-id 2","sdpMid": "0","sdpMLineIndex": 0},"transaction": "0WWSoZXbCxhA","session_id": 5109637625847547,"handle_id": 6769547295474368
}JBJ-WEBSOCKET RECV: {"janus": "trickle","candidate": {"candidate": "candidate:3993315412 1 udp 2122194687 192.168.248.1 60476 typ host generation 0 ufrag eHT/ network-id 3","sdpMid": "0","sdpMLineIndex": 0},"transaction": "DddvxlDlWuZN","session_id": 5109637625847547,"handle_id": 6769547295474368
}
JBJ-WEBSOCKET RECV: {"janus": "trickle","candidate": {"candidate": "candidate:2923601174 1 udp 2122129151 172.25.0.107 60477 typ host generation 0 ufrag eHT/ network-id 1 network-cost 10","sdpMid": "0","sdpMLineIndex": 0},"transaction": "HCdvw7ihHaaZ","session_id": 5109637625847547,"handle_id": 6769547295474368
}

Janus網關–>>Janus客戶端: Janus網關返回ack消息

JBJ-WEBSOCKET responses:Sending Janus API response({"janus": "ack","session_id": 5109637625847547,"transaction": "MHTliRCHqY5y"
}) to janus.transport.websockets (0x7f5cd400d3c0)JBJ-WEBSOCKET responses:Sending Janus API response({"janus": "ack","session_id": 5109637625847547,"transaction": "0WWSoZXbCxhA"
}) to janus.transport.websockets (0x7f5cd400d3c0)JBJ-WEBSOCKET responses:Sending Janus API response({"janus": "ack","session_id": 5109637625847547,"transaction": "DddvxlDlWuZN"
}) to janus.transport.websockets (0x7f5cd400d3c0)

學習資料分享

0voice · GitHub