talk/examples/objc/AppRTCDemo/ARDCEODTURNClient.m

/*
 * libjingle
 * Copyright 2014, Google Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  1. Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#import "ARDCEODTURNClient.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;

@implementation ARDCEODTURNClient {
  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 {
  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) {
    NSArray *turnServers = [NSArray array];
    if (error) {
      completionHandler(turnServers, error);
      return;
    }
    NSDictionary *dict = [NSDictionary dictionaryWithJSONData:data];
    turnServers = [RTCICEServer serversFromCEODJSONDictionary:dict];
    if (!turnServers) {
      NSError *responseError =
          [[NSError alloc] initWithDomain:kARDCEODTURNClientErrorDomain
                                     code:kARDCEODTURNClientErrorBadResponse
                                 userInfo:@{
            NSLocalizedDescriptionKey: @"Bad TURN response.",
          }];
      completionHandler(turnServers, responseError);
      return;
    }
    completionHandler(turnServers, nil);
  }];
}

@end