Using append:YES with operation.outputStream AFHTTPRequestOperation doesn't work - ios

Question

I am trying to download a text file and if this download is paused I am trying to append the rest of the file.
The problem is that i am starting to download the rest from the right point but the file is not appending it overrides the previous file.
Here is my source code:
+ (void) downloadFile:(NSManagedObject *)file {
NSString *url = [file valueForKey:#"path"];
NSString *fileName = [[file valueForKey:#"path"] lastPathComponent]; // TODO chnage to file ID (it will be good to add id before file name)
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:fileName];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:url]];
BOOL append = NO;
unsigned long long size = 0;
BOOL resumeOperation = NO;
if ([[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
resumeOperation = YES;
NSError *error = nil;
NSDictionary *dict = [[NSFileManager defaultManager] attributesOfItemAtPath:filePath error:&error];
size = [[dict objectForKey:NSFileSize] longLongValue];
if (!error) {
error = nil;
[[NSFileManager defaultManager] removeItemAtPath:filePath error:&error];
if (error) {
NSLog(#"Error removing old file: %#", [error localizedDescription]);
}
NSString *val = [NSString stringWithFormat:#"bytes=%lld-", size];
append = YES;
[request setValue:val forHTTPHeaderField:#"Range"];
}
}
AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request] ;
operation.outputStream = [NSOutputStream outputStreamToFileAtPath:filePath append:YES];
//gives more 10 minuts when the app is minimmized
[operation setShouldExecuteAsBackgroundTaskWithExpirationHandler:^{
[operation pause];
}];
[operation setDownloadProgressBlock:^(NSUInteger bytesRead, long long totalBytesRead, long long totalBytesExpectedToRead) {
totalBytesRead += size;
float percent = ((float)totalBytesRead) / (totalBytesExpectedToRead + size);
// TODO update database with bytes amount
NSLog(#"%.2f%% - [%d]", percent * 100, [[CoreDataManager getQueue] count]);
}];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"File downloaded succesffully!");
[self reportEndDownload:file withStatusCode:[NSNumber numberWithInt:DOWNLAOD_STATUS_COMPLETE]];
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
// NSLog(#"Error while downloading file: %#", [error localizedDescription]);
// ? ask about server corrupted files - here is a loop -----> Itay OK
[self reportEndDownload:file withStatusCode:[NSNumber numberWithInt:DOWNLOAF_STATUS_CONNECTION_ERROR]];
}];
if (resumeOperation ) {
[operation resume];
}else{
[operation start];
}
}

Answer 1

You can use AFDownloadRequestOperation to do this.
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:#"....zip"]];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path = [[paths objectAtIndex:0] stringByAppendingPathComponent:#"....zip"];
AFDownloadRequestOperation *operation = [[AFDownloadRequestOperation alloc] initWithRequest:request targetPath:path shouldResume:YES];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"Successfully downloaded file to %#", path);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
[operation setProgressiveDownloadProgressBlock:^(NSInteger bytesRead, long long totalBytesRead, long long totalBytesExpected, long long totalBytesReadForFile, long long totalBytesExpectedToReadForFile) {
NSLog(#"Operation%i: bytesRead: %d", 1, bytesRead);
NSLog(#"Operation%i: totalBytesRead: %lld", 1, totalBytesRead);
NSLog(#"Operation%i: totalBytesExpected: %lld", 1, totalBytesExpected);
NSLog(#"Operation%i: totalBytesReadForFile: %lld", 1, totalBytesReadForFile);
NSLog(#"Operation%i: totalBytesExpectedToReadForFile: %lld", 1, totalBytesExpectedToReadForFile);
}];
[operations addObject:operation];