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feat(TS) Migrate modules\sdp\LocalSdpMunger.js to TS(#2860)
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Lines changed: 222 additions & 199 deletions

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‎modules/sdp/LocalSdpMunger.js‎

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This file was deleted.

‎modules/sdp/LocalSdpMunger.spec.js‎

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@@ -99,7 +99,7 @@ describe('TransformSdpsForUnifiedPlan', () => {
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it('should add missing msid', () => {
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// P2P case only.
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localSdpMunger.tpc.isP2P = true;
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localSdpMunger._tpc.isP2P = true;
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const sdpStr = transform.write(SampleSdpStrings.firefoxP2pSdp);
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const desc = new RTCSessionDescription({

‎modules/sdp/LocalSdpMunger.ts‎

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import { isEqual } from 'lodash-es';
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import { MediaDirection } from '../../service/RTC/MediaDirection';
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import { MediaType } from '../../service/RTC/MediaType';
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import TraceablePeerConnection from '../RTC/TraceablePeerConnection';
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import browser from '../browser';
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import { MLineWrap, SdpTransformWrap } from './SdpTransformUtil';
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export interface ITPCSSRCInfo {
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groups: ITPCGroupInfo[];
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msid: string;
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ssrcs: number[];
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}
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export interface ITPCGroupInfo {
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semantics: string;
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ssrcs: number[];
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}
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export interface ISSRCAttribute {
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attribute: string;
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id: number;
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value: string;
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}
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/**
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* Fakes local SDP exposed to {@link JingleSessionPC} through the local description getter. Modifies the SDP, so that
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* the stream identifiers are unique across all of the local PeerConnections and that the source names and video types
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* are injected so that Jicofo can use them to identify the sources.
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*/
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export default class LocalSdpMunger {
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private _localEndpointId: string;
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private _tpc: TraceablePeerConnection;
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/**
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* Creates new <tt>LocalSdpMunger</tt> instance.
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*
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* @param {TraceablePeerConnection} tpc
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* @param {string} localEndpointId - The endpoint id of the local user.
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*/
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constructor(tpc: TraceablePeerConnection, localEndpointId: string) {
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this._tpc = tpc;
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this._localEndpointId = localEndpointId;
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}
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/**
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* Updates or adds a 'msid' attribute for the local sources in the SDP. Also adds 'sourceName' and 'videoType'
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* (if applicable) attributes. All other source attributes like 'cname', 'label' and 'mslabel' are removed since
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* these are not processed by Jicofo.
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*
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* @param {MLineWrap} mediaSection - The media part (audio or video) of the session description which will be
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* modified in place.
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* @returns {void}
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* @private
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*/
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private _transformMediaIdentifiers(mediaSection: MLineWrap, ssrcMap: Map<string, ITPCSSRCInfo>): void {
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const mediaType = mediaSection._mLine.type;
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const mediaDirection = mediaSection._mLine.direction;
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const sources = [ ...new Set(mediaSection._mLine.ssrcs?.map(s => s.id)) ];
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let trackId = mediaSection._mLine.msid?.split(' ')[1];
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let sourceName: string | undefined;
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if (ssrcMap.size) {
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const sortedSources = sources.slice().sort();
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for (const [ id, trackSsrcs ] of ssrcMap.entries()) {
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if (isEqual(sortedSources, [ ...trackSsrcs.ssrcs ].sort())) {
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sourceName = id;
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}
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}
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for (const source of sources) {
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if ((mediaDirection === MediaDirection.SENDONLY || mediaDirection === MediaDirection.SENDRECV)
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&& sourceName) {
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const msid = mediaSection.ssrcs.find(ssrc => ssrc.id === source && ssrc.attribute === 'msid');
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if (msid) {
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trackId = msid.value.split(' ')[1];
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}
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const generatedMsid = `${ssrcMap.get(sourceName).msid}-${this._tpc.id} ${trackId}-${this._tpc.id}`;
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const existingMsid = mediaSection.ssrcs
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.find(ssrc => ssrc.id === source && ssrc.attribute === 'msid');
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// Always overwrite msid since we want the msid to be in this format even if the browser generates
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// one. '<endpoint_id>-<mediaType>-<trackIndex>-<tpcId>' example - d8ff91-video-0-1
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if (existingMsid) {
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existingMsid.value = generatedMsid;
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} else {
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mediaSection.ssrcs.push({
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attribute: 'msid',
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id: source,
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value: generatedMsid
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});
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}
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// Inject source names as a=ssrc:3124985624 name:endpointA-v0
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mediaSection.ssrcs.push({
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attribute: 'name',
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id: source,
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value: sourceName
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});
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const videoType = this._tpc.getLocalVideoTracks()
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.find(track => track.getSourceName() === sourceName)
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?.getVideoType();
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if (mediaType === MediaType.VIDEO && videoType) {
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// Inject videoType as a=ssrc:1234 videoType:desktop.
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mediaSection.ssrcs.push({
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attribute: 'videoType',
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id: source,
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value: videoType
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});
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}
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}
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}
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}
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// Ignore the 'label' and 'mslabel' attributes.
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mediaSection.ssrcs
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= mediaSection.ssrcs.filter(ssrc => ssrc.attribute !== 'label' && ssrc.attribute !== 'mslabel');
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// Remove the 'cname' attribute on Firefox as a=ssrc line with only 'cname' attribute are present in the SDP
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// for recvonly SSRCs generated by createAnswer. These do not have to be signaled to the peers.
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if (browser.isFirefox()) {
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mediaSection.ssrcs = mediaSection.ssrcs.filter(ssrc => ssrc.attribute !== 'cname');
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}
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// On FF when the user has started muted create answer will generate a recv only SSRC. We don't want to signal
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// this SSRC in order to reduce the load of the xmpp server for large calls. Therefore the SSRC needs to be
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// removed from the SDP.
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//
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// For all other use cases (when the user has had media but then the user has stopped it) we want to keep the
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// receive only SSRCs in the SDP. Otherwise source-remove will be triggered and the next time the user add a
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// track we will reuse the SSRCs and send source-add with the same SSRCs. This is problematic because of issues
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// on Chrome and FF (https://bugzilla.mozilla.org/show_bug.cgi?id=1768729) when removing and then adding the
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// same SSRC in the remote sdp the remote track is not rendered.
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if (browser.isFirefox()
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&& (mediaDirection === MediaDirection.RECVONLY || mediaDirection === MediaDirection.INACTIVE)
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&& (
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(mediaType === MediaType.VIDEO && !this._tpc._hasHadVideoTrack)
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|| (mediaType === MediaType.AUDIO && !this._tpc._hasHadAudioTrack)
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)
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) {
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mediaSection.ssrcs = undefined;
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mediaSection.ssrcGroups = undefined;
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}
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}
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/**
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* This transformation will make sure that stream identifiers are unique across all of the local PeerConnections
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* even if the same stream is used by multiple instances at the same time. It also injects 'sourceName' and
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* 'videoType' attribute.
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*
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* @param {RTCSessionDescription} sessionDesc - The local session description (this instance remains unchanged).
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* @param {Map<string, TPCSSRCInfo>} ssrcMap - The SSRC and source map for the local tracks.
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* @return {RTCSessionDescription} - Transformed local session description
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* (a modified copy of the one given as the input).
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*/
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transformStreamIdentifiers(sessionDesc: RTCSessionDescription, ssrcMap: Map<string, ITPCSSRCInfo>): RTCSessionDescription {
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if (!sessionDesc?.sdp || !sessionDesc.type) {
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return sessionDesc;
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}
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const transformer = new SdpTransformWrap(sessionDesc.sdp);
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const audioMLine = transformer.selectMedia(MediaType.AUDIO)?.[0];
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if (audioMLine) {
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this._transformMediaIdentifiers(audioMLine, ssrcMap);
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}
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const videoMlines = transformer.selectMedia(MediaType.VIDEO);
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if (videoMlines && Array.isArray(videoMlines)) {
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for (const videoMLine of videoMlines) {
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this._transformMediaIdentifiers(videoMLine, ssrcMap);
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}
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}
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return {
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sdp: transformer.toRawSDP(),
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type: sessionDesc.type
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} as RTCSessionDescription;
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}
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}

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