Add RTCEventLog API to ObjC.

webrtc/examples/objc/AppRTCDemo/ARDAppClient.m

 /*
  *  Copyright 2014 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 37 matching lines @@
 static NSInteger const kARDAppClientErrorCreateSDP = -3;
 static NSInteger const kARDAppClientErrorSetSDP = -4;
 static NSInteger const kARDAppClientErrorInvalidClient = -5;
 static NSInteger const kARDAppClientErrorInvalidRoom = -6;
 static NSString * const kARDMediaStreamId = @"ARDAMS";
 static NSString * const kARDAudioTrackId = @"ARDAMSa0";
 static NSString * const kARDVideoTrackId = @"ARDAMSv0";
 
 // TODO(tkchin): Remove guard once rtc_sdk_common_objc compiles on Mac.
 #if defined(WEBRTC_IOS)
-// TODO(tkchin): Add this as a UI option.
+// TODO(tkchin): Add these as UI options.
 static BOOL const kARDAppClientEnableTracing = NO;
+static BOOL const kARDAppClientEnableRtcEventLog = YES;
+static int64_t const kARDAppClientRtcEventLogMaxSizeInBytes = 5e6;  // 5 MB.
 #endif
 
 // We need a proxy to NSTimer because it causes a strong retain cycle. When
 // using the proxy, |invalidate| must be called before it properly deallocs.
 @interface ARDTimerProxy : NSObject
 
 - (instancetype)initWithInterval:(NSTimeInterval)interval
                          repeats:(BOOL)repeats
                     timerHandler:(void (^)(void))timerHandler;
 - (void)invalidate;
@@ skipping 150 matching lines @@
                  isLoopback:(BOOL)isLoopback
                 isAudioOnly:(BOOL)isAudioOnly {
   NSParameterAssert(roomId.length);
   NSParameterAssert(_state == kARDAppClientStateDisconnected);
   _isLoopback = isLoopback;
   _isAudioOnly = isAudioOnly;
   self.state = kARDAppClientStateConnecting;
 
 #if defined(WEBRTC_IOS)
   if (kARDAppClientEnableTracing) {
-    NSArray *paths = NSSearchPathForDirectoriesInDomains(
-        NSDocumentDirectory, NSUserDomainMask, YES);
-    NSString *documentsDirPath = paths.firstObject;
-    NSString *filePath =
-        [documentsDirPath stringByAppendingPathComponent:@"webrtc-trace.txt"];
+    NSString *filePath = [self documentsFilePathForFileName:@"webrtc-trace.txt"];
     RTCStartInternalCapture(filePath);
   }
 #endif
 
   // Request TURN.
   __weak ARDAppClient *weakSelf = self;
   [_turnClient requestServersWithCompletionHandler:^(NSArray *turnServers,
                                                      NSError *error) {
     if (error) {
       RTCLogError("Error retrieving TURN servers: %@",
@@ skipping 62 matching lines @@
   }
   _clientId = nil;
   _roomId = nil;
   _isInitiator = NO;
   _hasReceivedSdp = NO;
   _messageQueue = [NSMutableArray array];
   _peerConnection = nil;
   self.state = kARDAppClientStateDisconnected;
 #if defined(WEBRTC_IOS)
   RTCStopInternalCapture();
+  [_factory stopRtcEventLog];

[Chuck, 2016/06/14 14:01:17]

Do you need the #if guards here?

[tkchin_webrtc, 2016/06/14 17:40:59]

Prob not.

[Chuck, 2016/06/14 19:36:44]

I think I confused myself, I didn't see them in the original CL (since they were
already there), and was actually suggesting to add them if you needed them. 

 #endif
 }
 
 #pragma mark - ARDSignalingChannelDelegate
 
 - (void)channel:(id<ARDSignalingChannel>)channel
     didReceiveMessage:(ARDSignalingMessage *)message {
   switch (message.type) {
     case kARDSignalingMessageTypeOffer:
     case kARDSignalingMessageTypeAnswer:
@@ skipping 164 matching lines @@
         [strongSelf peerConnection:strongSelf.peerConnection
             didCreateSessionDescription:sdp
                                   error:error];
       }];
     }
   });
 }
 
 #pragma mark - Private
 
+#if defined(WEBRTC_IOS)
+
+- (NSString *)documentsFilePathForFileName:(NSString *)fileName {
+  NSParameterAssert(fileName.length);
+  NSArray *paths = NSSearchPathForDirectoriesInDomains(
+      NSDocumentDirectory, NSUserDomainMask, YES);
+  NSString *documentsDirPath = paths.firstObject;
+  NSString *filePath =
+      [documentsDirPath stringByAppendingPathComponent:fileName];
+  return filePath;
+}
+
+#endif
+
 - (BOOL)hasJoinedRoomServerRoom {
   return _clientId.length;
 }
 
 // Begins the peer connection connection process if we have both joined a room
 // on the room server and tried to obtain a TURN server. Otherwise does nothing.
 // A peer connection object will be created with a stream that contains local
 // audio and video capture. If this client is the caller, an offer is created as
 // well, otherwise the client will wait for an offer to arrive.
 - (void)startSignalingIfReady {
   if (!_isTurnComplete || !self.hasJoinedRoomServerRoom) {
     return;
   }
   self.state = kARDAppClientStateConnected;
 
+#if defined(WEBRTC_IOS)
+  // Start event log.
+  if (kARDAppClientEnableRtcEventLog) {
+    NSString *filePath = [self documentsFilePathForFileName:@"webrtc-rtceventlog"];
+    [_factory startRtcEventLogWithFilePath:filePath

[Chuck, 2016/06/14 14:01:17]

Your comment suggests this is temporary, but should you check the return value
here and log the result?

[tkchin_webrtc, 2016/06/14 17:40:59]

Done.

+                            maxSizeInBytes:kARDAppClientRtcEventLogMaxSizeInBytes];
+  }
+#endif
+
   // Create peer connection.
   RTCMediaConstraints *constraints = [self defaultPeerConnectionConstraints];
   RTCConfiguration *config = [[RTCConfiguration alloc] init];
   config.iceServers = _iceServers;
   _peerConnection = [_factory peerConnectionWithConfiguration:config
                                                   constraints:constraints
                                                      delegate:self];
   // Create AV senders.
   [self createAudioSender];
   [self createVideoSender];
@@ skipping 263 matching lines @@
                                          code:kARDAppClientErrorInvalidRoom
                                      userInfo:@{
         NSLocalizedDescriptionKey: @"Invalid room.",
       }];
       break;
   }
   return error;
 }
 
 @end