Process Firefox SDP with media port 0 (#788)

* Fix audio ranker failure during switching

* Process Firefox SDP with media port 0

Author: starwarfan

source/agent/webrtc/sdpInfo.js

@@ -29,6 +29,16 @@ class SdpInfo {
     });
   }
 
+  bundleMids() {
+    const bundles = this.obj.groups.find(g => g.type === 'BUNDLE');
+    return bundles.mids.split(' ');
+  }
+
+  setBundleMids(mids) {
+    const bundles = this.obj.groups.find(g => g.type === 'BUNDLE');
+    bundles.mids = mids.join(' ');
+  }
+
   mids() {
     return this.obj.media.map(mediaInfo => mediaInfo.mid.toString());
   }
@@ -321,6 +331,30 @@ class SdpInfo {
     });
   }
 
+  isMediaClosed(mid) {
+    const mediaInfo = this.media(mid);
+    if (!mediaInfo) {
+      return true;
+    }
+    if (mediaInfo.port === 0 && mediaInfo.direction === 'inactive') {
+      return true;
+    }
+    return false;
+  }
+
+  closeMedia(mid) {
+    const mediaInfo = this.media(mid);
+    if (mediaInfo) {
+      mediaInfo.direction = 'inactive';
+      mediaInfo.port = 0;
+      delete mediaInfo.ext;
+      delete mediaInfo.ssrcs;
+      delete mediaInfo.ssrcGroups;
+      delete mediaInfo.simulcast;
+      delete mediaInfo.rids;
+    }
+  }
+
   compareMedia(sdp) {
     const diffMids = [];
     this.obj.media.forEach(m1 => {

source/agent/webrtc/wrtcConnection.js

@@ -441,7 +441,7 @@ module.exports = function (spec, on_status, on_track) {
     // Check Media MID with saved operation
     if (!operationMap.has(mid)) {
       log.warn(`MID ${mid} in offer has no mapped operations (disabled)`);
-      remoteSdp.setMediaPort(mid, 0);
+      remoteSdp.closeMedia(mid);
       return;
     }
     if (operationMap.get(mid).sdpDirection !== remoteSdp.mediaDirection(mid)) {
@@ -452,9 +452,10 @@ module.exports = function (spec, on_status, on_track) {
       log.warn(`MID ${mid} in offer has conflict media type with operation`);
       return;
     }
-    if (operationMap.get(mid).enabled && (remoteSdp.getMediaPort(mid) === 0)) {
-      log.warn(`MID ${mid} in offer has conflict port with operation (disabled)`);
+    if (operationMap.get(mid).enabled && remoteSdp.isMediaClosed(mid)) {
+      log.warn(`MID ${mid} in offer has conflict closed state (disabled)`);
       operationMap.get(mid).enabled = false;
+      return;
     }
 
     // Determine media format in offer
@@ -501,34 +502,28 @@ module.exports = function (spec, on_status, on_track) {
       const addedMids = [];
       const removedMids = [];
 
-      for (let cmid of changedMids) {
+      for (let cmid of laterSdp.mids()) {
         const oldMedia = remoteSdp.media(cmid);
         if (!oldMedia) {
           // Add media
           const tempSdp = laterSdp.singleMediaSdp(cmid);
           remoteSdp.mergeMedia(tempSdp);
           addedMids.push(cmid);
-        } else if (laterSdp.getMediaPort(cmid) === 0) {
+        } else if (laterSdp.isMediaClosed(cmid)) {
           // Remove media
-          remoteSdp.setMediaPort(cmid, 0);
-          localSdp.setMediaPort(cmid, 0);
-          removedMids.push(cmid);
-        } else if (laterSdp.mediaDirection(cmid) === 'inactive') {
-          // Disable media
-          remoteSdp.media(cmid).direction = 'inactive';
-          localSdp.media(cmid).direction = 'inactive';
+          remoteSdp.closeMedia(cmid);
           removedMids.push(cmid);
         } else {
-          // May be port or direction change
-          log.debug(`MID ${cmid} port or direction change`);
+          // Treat as no change
+          log.debug(`MID ${cmid} no change`);
         }
       }
 
       let opId = null;
       for (let mid of addedMids) {
         processOfferMedia(mid);
         localSdp.mergeMedia(remoteSdp.singleMediaSdp(mid).answer());
-        if (remoteSdp.getMediaPort(mid) !== 0) {
+        if (!remoteSdp.isMediaClosed(mid)) {
           opId = setupTransport(mid);
         }
       }
@@ -540,10 +535,11 @@ module.exports = function (spec, on_status, on_track) {
       }
 
       for (let mid of removedMids) {
-        // processOfferMedia(mid);
+        localSdp.closeMedia(mid);
+        // Should already be destroyed by 'removeTrackOperation'
         // destroyTransport(mid);
       }
-
+      localSdp.setBundleMids(remoteSdp.bundleMids());
       // Produce answer
       const message = localSdp.toString();
       log.debug('Answer SDP', message);