How to getStats() in WebRTC iOS SDK in Swift? - swift

Question

I am trying to get ICE Candidate Pair Stats in iOS SDK in Swift. I see this specific interface: statsForTrack but I am unsure about how to use it. Has anybody done this before?

Answer 1

you can use stats function in PeerConnection like this:
peerConnection.stats(for: RTCMediaStreamTrack?, statsOutputLevel: .debug, completionHandler: { reports in
// reports here
}
you can set nil for parameter RTCMediaStreamTrack for get all reports or set special mediaStreamTack to get reports only this mediaStream.
peerConnection.stats(for: nil, statsOutputLevel: .debug, completionHandler: { reports in
// reports all mediaStreams
}

Answer 2

In your class where you creating peerConnection there you can start a timer like below:
statsTimer = [NSTimer scheduledTimerWithTimeInterval:2.0
target:self
selector:#selector(getStats)
userInfo:nil
repeats:YES];
And getStats be like this:
- (void)getStats {
NSArray<RTCMediaStreamTrack *> *tracks = mediaStream.videoTracks;
tracks = [tracks arrayByAddingObjectsFromArray:// Here mediaStream is instance of RTCMediaStream (NSArray<RTCMediaStreamTrack *> *)_publishStream.mediaStream.audioTracks];
for (RTCMediaStreamTrack *track in tracks) {
[peerConnection statsForTrack:track
statsOutputLevel:RTCStatsOutputLevelStandard
completionHandler:^(NSArray<RTCLegacyStatsReport *> * _Nonnull stats) {
for (RTCLegacyStatsReport *stat in stats) {
if ([stat.type isEqualToString:kRTCStatsTypeSSRC]) {
[self processRTCLegacyStatsReport:stat];
[statsBySSRC setObject:#{ kRTCStatsBytesSent: [stat.values objectForKey:kRTCStatsBytesSent],
kRTCStatsLastDate: [NSDate date]
} forKey:[stat.values objectForKey:kRTCStatsTypeSSRC]];
}
}
}];
}
}
- (void)processRTCLegacyStatsReport:(RTCLegacyStatsReport *)statsReport {
NSString *ssrc = [statsReport.values objectForKey:kRTCStatsTypeSSRC];
NSString *mediaType = [statsReport.values objectForKey:kRTCStatsMediaTypeKey];
unsigned long kbps = [self calculateBitrateForStatsReport:statsReport];
L_INFO(#"RTC Publishing %# Stats Type: %#, ID: %# Dict: %#",
mediaType, statsReport.type, statsReport.reportId, statsReport.values);
L_INFO(#"RTC Publishing %# kbps: %lld", mediaType, kbps)
}
- (unsigned long)calculateBitrateForStatsReport:(RTCLegacyStatsReport *)statsReport {
NSString *ssrc = [statsReport.values objectForKey:kRTCStatsTypeSSRC];
unsigned long bytesSent = [[statsReport.values objectForKey:kRTCStatsBytesSent] intValue];
unsigned long lastBytesSent = [[[statsBySSRC objectForKey:ssrc] objectForKey:kRTCStatsBytesSent] intValue];
NSDate *lastStatsDate = [[statsBySSRC objectForKey:ssrc] objectForKey:kRTCStatsLastDate];
NSTimeInterval seconds = [lastStatsDate timeIntervalSinceNow];
unsigned long kbps = (((bytesSent - lastBytesSent) * 8) / fabs(seconds)) / 1000.0;
return kbps;
}