NSURLSession and stream upload in background

Question

I have some problems with using NSURLSession to upload photos from Asset Library to the server.

At first NSURLSession doesn\'t support stre

Answer 1

A clean workaround will be to create a NSOperation which will copy the file from the asset library to your temporary folder using NSStream, so you won't get a crash in case of a huge file, when the operation completes you schedule a upload of that temporary file, when the upload finishes you delete it.

In my case, i need to send the file in multipart format so the creation of the temporary file is necessary but i encounter a problem in uploading large files, more then 2 Gb, example movies over 20 minutes.

Answer 2

You can't upload NSData in background you need to upload file format. You can create it by directory path

Answer 3

Convert to NSData and copy and write in app folder

ALAsset *asset = [cameraRollUploadImages objectAtIndex:startCount];
ALAssetRepresentation *representation = [asset defaultRepresentation];

// create a buffer to hold the data for the asset's image
uint8_t *buffer = (Byte *)malloc(representation.size);// copy the data from the asset into the buffer
NSUInteger length = [representation getBytes:buffer 
                                  fromOffset:0 
                                      length:representation.size 
                                       error:nil];

// convert the buffer into a NSData object, free the buffer after
NSData *image = [[NSData alloc] initWithBytesNoCopy:buffer 
                                             length:representation.size
                                       freeWhenDone:YES];

Answer 4

Right now, there is no way otherthan saving the picture to local file system or temp directory.

Following code make sure your data won't be lost with exif tags. (ALAsset => NSData)

ALAssetRepresentation *assetRepresentation = [(ALAsset *)assetBeingUploaded defaultRepresentation];
uint8_t *buffer = (uint8_t *)malloc(sizeof(uint8_t)*[assetRepresentation size]);
NSUInteger buffered = 0;
if (buffer != NULL)
buffered = [assetRepresentation getBytes:buffer fromOffset:0.0 length:assetRepresentation.size error:nil];
self.imageBeingUploaded = [NSData dataWithBytesNoCopy:buffer length:buffered freeWhenDone:YES];

The upload task in background session doesn't support completion handler. We should go for.,

- (NSURLSessionUploadTask *)uploadTaskWithRequest:(NSURLRequest *)request fromFile:(NSURL *)fileURL;  

I doubt how do we get the response headers or body in case if we are using background session & uploadtask with request using file?