0 Replies
      Latest reply on Jun 14, 2019 1:58 PM by rmpangahds
      rmpangahds Level 1 Level 1 (0 points)



        The problem I am seeing occurs only for large file uploads (300-500 MBs). What I am observing is that  iOS sometimes does NOT call didCompleteWithError even after my server sends a response.  In the client logs I can see that the didSendBodyData method gets called several times. Which is expected, however it does not seem to stop even after sending all the bytes.  I have also noticed that sometimes the taskId changes or the totalBytesSent gets reset. Which does not make any sense since I have not queued up another upload task. I only called resume once.


        Also note: This behavior happens when the app is in the foreground. I have not attempted testing background uploads yet. Additionally I have tired using the default session and still observe the same behavior.


        Everything works as expected the file is small.(~50 Mbs). The didRecieveData method gets called along with the didCompleteWithError method.


        Below are some code snippets of the background task:




        - (void)URLSession:(NSURLSession *)session 
                      task:(NSURLSessionTask *)task 
            NSNumber* taskId = [NSNumber numberWithUnsignedInteger:task.taskIdentifier]; 
            AwLog(@"DidSendBodyData for taskID: %@  BytesSent: %lld TotalBytesSent: %lld ExpectedToSend: %lld\n", taskId, bytesSent, totalBytesSent, totalBytesExpectedToSend); 
            if (updateFileProgressCallback != NULL) 
                updateFileProgressCallback(bytesSent, totalBytesSent); 

        Here is by backgroundSession.


        - (NSURLSession *)backgroundSession 
            static NSURLSession *session = nil; 
            static dispatch_once_t onceToken; 
            dispatch_once(&onceToken, ^{ 
               NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration backgroundSessionConfigurationWithIdentifier: KEY_BACKGROUND_SESSSION_ID]; 
                configuration.discretionary = YES; 
                configuration.sessionSendsLaunchEvents = YES; 
                configuration.URLCache = nil; 
                bool wifiOnly = [ClientConfiguration.sharedInstance isWifiOnlyEnabled]; 
                if (wifiOnly) 
                    configuration.allowsCellularAccess = false; 
                NSOperationQueue* delegateMainQueue = [NSOperationQueue mainQueue]; 
                delegateMainQueue.maxConcurrentOperationCount = 1; 
                session = [NSURLSession sessionWithConfiguration:configuration delegate:self delegateQueue: delegateMainQueue]; 
            return session; 


        Creating the upload task


        NSURLSession* backgroundSession = [FileOperationsSessionDelegate.sharedInstance backgroundSession]; 
                               NSMutableString *file = [[NSMutableString alloc] initWithString:absLocalPath]; 
                               [file insertString:@"file://" atIndex:0]; 
                               NSURL* fileToBeUploaded = [NSURL URLWithString:file]; 
                               NSURLSessionUploadTask* uploadTask = [backgroundSession uploadTaskWithRequest:urlRequest fromFile:fileToBeUploaded]; 
                               uploadTask.countOfBytesClientExpectsToSend = self.uploadSizeBytes; 
                               uploadTask.countOfBytesClientExpectsToReceive = 450; 
        ConnectionCallback uploadCompleteCallback = ^(NSURLResponse *  response, NSData * data,  NSError *  error) { 
        // A callback to complete the file upload. It will update the UI and notify the user  
        // on how the upload went.  
          BytesUploadedCallback updateFileProgressCallback = ^(long bytesWritten, long totalBytesWritten) 
        // A callback that will update the progress bar. 
                               [FileOperationsSessionDelegate.sharedInstance setUploadCallback:uploadCompleteCallback]; 
                               [FileOperationsSessionDelegate.sharedInstance setConnectionCallback:updateFileProgressCallback];; 
                               [uploadTask resume]; 


        Any help with this will be greatly apperiated.



        Thanks : )




        iOS version 12.3

        Device: iPad Pro 11

        Xcode:  10.1