Update ice server provider response format in iOS AppRTCMobile

webrtc/examples/objc/AppRTCMobile/ARDTURNClient.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.
  */
 
-#import "ARDCEODTURNClient.h"
+#import "ARDTURNClient+Internal.h"
 
 #import "ARDUtilities.h"
 #import "RTCIceServer+JSON.h"
 
 // TODO(tkchin): move this to a configuration object.
-static NSString *kTURNOriginURLString = @"https://apprtc.appspot.com";
-static NSString *kARDCEODTURNClientErrorDomain = @"ARDCEODTURNClient";
-static NSInteger kARDCEODTURNClientErrorBadResponse = -1;
+static NSString *kTURNRefererURLString = @"https://appr.tc";
+static NSString *kARDTURNClientErrorDomain = @"ARDTURNClient";
+static NSInteger kARDTURNClientErrorBadResponse = -1;
 
-@implementation ARDCEODTURNClient {
+@implementation ARDTURNClient {
   NSURL *_url;
 }
 
 - (instancetype)initWithURL:(NSURL *)url {
   NSParameterAssert([url absoluteString].length);
   if (self = [super init]) {
     _url = url;
   }
   return self;
 }
 
 - (void)requestServersWithCompletionHandler:
-    (void (^)(NSArray *turnServers,
-              NSError *error))completionHandler {
+    (void (^)(NSArray *turnServers, NSError *error))completionHandler {
+
   NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:_url];
-  // We need to set origin because TURN provider whitelists requests based on
-  // origin.
-  [request addValue:@"Mozilla/5.0" forHTTPHeaderField:@"user-agent"];
-  [request addValue:kTURNOriginURLString forHTTPHeaderField:@"origin"];
   [NSURLConnection sendAsyncRequest:request
+                  completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
+      if (error) {
+        completionHandler(nil, error);
+        return;
+      }
+      NSDictionary *responseDict = [NSDictionary dictionaryWithJSONData:data];
+      NSString *iceServerUrl = responseDict[@"ice_server_url"];
+      [self makeTurnServerRequestToURL:[NSURL URLWithString:iceServerUrl]
+                 WithCompletionHandler:completionHandler];
+    }];
+}
+
+#pragma mark - Private
+
+- (void)makeTurnServerRequestToURL:(NSURL *)url
+             WithCompletionHandler:(void (^)(NSArray *turnServers,
+                                             NSError *error))completionHandler {
+  NSMutableURLRequest *iceServerRequest = [NSMutableURLRequest requestWithURL:url];
+  iceServerRequest.HTTPMethod = @"POST";
+  [iceServerRequest addValue:kTURNRefererURLString forHTTPHeaderField:@"referer"];
+  [NSURLConnection sendAsyncRequest:iceServerRequest
                   completionHandler:^(NSURLResponse *response,
                                       NSData *data,
                                       NSError *error) {
-    NSArray *turnServers = [NSArray array];
-    if (error) {
-      completionHandler(nil, error);
-      return;
-    }
-    NSDictionary *dict = [NSDictionary dictionaryWithJSONData:data];
-    turnServers = @[ [RTCIceServer serverFromCEODJSONDictionary:dict] ];
-    if (!turnServers) {
-      NSError *responseError =
-          [[NSError alloc] initWithDomain:kARDCEODTURNClientErrorDomain
-                                     code:kARDCEODTURNClientErrorBadResponse
+      if (error) {
+        completionHandler(nil, error);
+        return;
+      }
+      NSDictionary *turnResponseDict = [NSDictionary dictionaryWithJSONData:data];
+      NSMutableArray *turnServers = [NSMutableArray array];
+      [turnResponseDict[@"iceServers"] enumerateObjectsUsingBlock:
+                         ^(NSDictionary *obj, NSUInteger idx, BOOL *stop){
+          [turnServers addObject:[RTCIceServer serverFromJSONDictionary:obj]];
+        }];
+      if (!turnServers) {
+        NSError *responseError =
+          [[NSError alloc] initWithDomain:kARDTURNClientErrorDomain
+                                     code:kARDTURNClientErrorBadResponse
                                  userInfo:@{
             NSLocalizedDescriptionKey: @"Bad TURN response.",
-          }];
-      completionHandler(turnServers, responseError);
-      return;
-    }
-    completionHandler(turnServers, nil);
-  }];
+            }];
+        completionHandler(nil, responseError);
+        return;
+      }
+      completionHandler(turnServers, nil);
+    }];
 }
 
 @end