AWS S3 Upload works on Simulator but not on Device - ios

Question

I'm encountering an interesting problem. Trying to upload a file to AWS S3, it works perfectly when run on a simulator, also when run on a connected device (DEBUG mode). But when I package the app and deploy it to a device, it doesn't work. I keep getting "Request Timed Out".
This is my code,
- (void)uploadFileAtPath:(NSString *)filePath completionHandler:(void (^)(NSString *, NSError *))handler {
NSString *fileName = [filePath lastPathComponent];
AWSS3GetPreSignedURLRequest *getPreSignedURLRequest = [AWSS3GetPreSignedURLRequest new];
getPreSignedURLRequest.bucket = self.bucketName;
getPreSignedURLRequest.key = fileName;
getPreSignedURLRequest.HTTPMethod = AWSHTTPMethodPUT;
getPreSignedURLRequest.expires = [NSDate dateWithTimeIntervalSinceNow:3600];
NSString *fileContentTypeStr = #"application/zip";
getPreSignedURLRequest.contentType = fileContentTypeStr;
[[[AWSS3PreSignedURLBuilder defaultS3PreSignedURLBuilder] getPreSignedURL:getPreSignedURLRequest]
continueWithBlock:^id(AWSTask *task) {
if (task.error) {
NSLog(#"Error: %#",task.error);
} else {
NSURL *presignedURL = task.result;
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:presignedURL];
request.cachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
[request setHTTPMethod:#"PUT"];
[request setValue:fileContentTypeStr forHTTPHeaderField:#"Content-Type"];
[request setHTTPBody:[NSData dataWithContentsOfFile:filePath]];
NSURLSessionConfiguration* config = [NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSession * session = [NSURLSession sessionWithConfiguration:config delegate:nil delegateQueue:nil];
NSURLSessionDataTask* uploadTask = [session dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
if (error) {
NSLog(#"URL Session Task Failed: %#", [error localizedDescription]);
}
else {
NSLog(#"URL Session Task Succeeded: HTTP %ld", ((NSHTTPURLResponse*)response).statusCode);
}
handler([[((NSHTTPURLResponse*)response).URL.absoluteString componentsSeparatedByString:#"?"] firstObject], error);
}];
[uploadTask resume];
}
return nil;
}];
}
And this is the error I get (obfuscated sensitive parts) -
Error: The request timed out.,
UserInfo: {
NSErrorFailingURLKey = "https://s3.amazonaws.com/bucketname/file-2-10-2015-10-13PM.zip?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIHY7KKHBLYOPMTPA%2F20151003%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20151003T051306Z&X-Amz-Expires=3599&X-Amz-SignedHeaders=content-type%3Bhost&X-Amz-Signature=504e1f5083116as09dc6a04c3b4152816a8d9e8bccff8f4ea0cbss9fcdc21eac";
NSErrorFailingURLStringKey = "https://s3.amazonaws.com/bucketname/file-2-10-2015-10-13PM.zip?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIHY7KKHBLYOPMTPA%2F20151003%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20151003T051306Z&X-Amz-Expires=3599&X-Amz-SignedHeaders=content-type%3Bhost&X-Amz-Signature=504e1f5083116as09dc6a04c3b4152816a8d9e8bccff8f4ea0cbss9fcdc21eac";
NSLocalizedDescription = "The request timed out.";
NSUnderlyingError = "Error Domain=kCFErrorDomainCFNetwork Code=-1001 \"(null)\" UserInfo={_kCFStreamErrorDomainKey=4, _kCFStreamErrorCodeKey=-2102}";
"_kCFStreamErrorCodeKey" = "-2102";
"_kCFStreamErrorDomainKey" = 4;
}
I have no idea what is going wrong here! Help much appreciated.
While the device connected to Xcode, I also got the URL out and uploaded the file via cURL. FWIW, that works too!

Answer 1

After 2 days, I finally found the problem! This was the part of the code I did not post, but it is how I was initializing the AWS Client.
AWSStaticCredentialsProvider *cp = [[AWSStaticCredentialsProvider alloc] initWithAccessKey:accesskey secretKey:secretKey];
AWSServiceConfiguration* config = [[AWSServiceConfiguration alloc] initWithRegion:AWSRegionUSEast1 credentialsProvider:cp];
AWSServiceManager.defaultServiceManager.defaultServiceConfiguration = config;
Now, there was another library that I was using which did exactly the same thing, but with different credentials to a different bucket. Since this other library was getting called after my code, I was having problems with uploading the file. Now why was the error Request Timed Out instead of Invalid Credentials, is something I haven't found out yet.
I changed the initialization code to this --
AWSStaticCredentialsProvider *cp = [[AWSStaticCredentialsProvider alloc] initWithAccessKey:accesskey secretKey:secretKey];
AWSServiceConfiguration* config = [[AWSServiceConfiguration alloc] initWithRegion:AWSRegionUSEast1 credentialsProvider:cp];
[AWSS3TransferManager registerS3TransferManagerWithConfiguration:config forKey:AWSLogFilesUploaderKey];
And obtained an instance of AWSS3TransferManager like this --
AWSS3TransferManager* tm = [AWSS3TransferManager S3TransferManagerForKey:AWSLogFilesUploaderKey];
And then everything went smooth!