NSURLSession:
=============
NSURL *URL = [NSURL URLWithString:@"http://example.com"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];
[NSURLConnection sendAsynchronousRequest:request
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
// ...
}];
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Data tasks can be created with either an NSURL or NSURLRequest (the former being a shortcut for a standard GET request to that URL):
NSURL *URL = [NSURL URLWithString:@"http://example.com"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];
NSURLSession *session = [NSURLSession sharedSession];
NSURLSessionDataTask *task = [session dataTaskWithRequest:request
completionHandler:
^(NSData *data, NSURLResponse *response, NSError *error) {
// ...
}];
[task resume];
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Upload tasks can also be created with a request and either an NSData object for a URL to a local file to upload:
NSURL *URL = [NSURL URLWithString:@"http://example.com/upload"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];
NSData *data = ...;
NSURLSession *session = [NSURLSession sharedSession];
NSURLSessionUploadTask *uploadTask = [session uploadTaskWithRequest:request
fromData:data
completionHandler:
^(NSData *data, NSURLResponse *response, NSError *error) {
// ...
}];
[uploadTask resume];
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Download requests take a request as well, but differ in their completionHandler. Rather than being returned all at once upon completion, as data and upload tasks, download tasks have their data written to a local temp file. It’s the responsibility of the completion handler to move the file from its temporary location to a permanent location.
NSURL *URL = [NSURL URLWithString:@"http://example.com/file.zip"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];
NSURLSession *session = [NSURLSession sharedSession];
NSURLSessionDownloadTask *downloadTask = [session downloadTaskWithRequest:request
completionHandler:
^(NSURL *location, NSURLResponse *response, NSError *error) {
NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
NSURL *documentsDirectoryURL = [NSURL fileURLWithPath:documentsPath];
NSURL *documentURL = [documentsDirectoryURL URLByAppendingPathComponent:[response
suggestedFilename]];
[[NSFileManager defaultManager] moveItemAtURL:location
toURL:documentURL
error:nil];
}];
[downloadTask resume];
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NSURLSessionConfiguration:
==========================
NSString *imageUrl =
@"http://www.raywenderlich.com/images/store/iOS7_PDFonly_280@2x_authorTBA.png";
NSURLSessionConfiguration *sessionConfig =
[NSURLSessionConfiguration defaultSessionConfiguration];
NSString *userPasswordString = [NSString stringWithFormat:@"%@:%@", user, password];
NSData * userPasswordData = [userPasswordString dataUsingEncoding:NSUTF8StringEncoding];
NSString *base64EncodedCredential = [userPasswordData base64EncodedStringWithOptions:0];
NSString *authString = [NSString stringWithFormat:@"Basic %@", base64EncodedCredential];
NSString *userAgentString = @"AppName/com.example.app (iPhone 5s; iOS 7.0.2; Scale/2.0)";
sessionConfig.HTTPAdditionalHeaders = @{@"Accept": @"application/json",
@"Accept-Language": @"en",
@"Authorization": authString,
@"User-Agent": userAgentString};
sessionConfig.allowsCellularAccess = NO;
sessionConfig.timeoutIntervalForRequest = 30.0;
sessionConfig.timeoutIntervalForResource = 60.0;
sessionConfig.HTTPMaximumConnectionsPerHost = 1;
NSURLSession *session =
[NSURLSession sessionWithConfiguration:sessionConfig
delegate:self
delegateQueue:nil];
// 1
NSURLSessionDownloadTask *getImageTask =
[session downloadTaskWithURL:[NSURL URLWithString:imageUrl]
completionHandler:^(NSURL *location,
NSURLResponse *response,
NSError *error) {
// 2
UIImage *downloadedImage =
[UIImage imageWithData:
[NSData dataWithContentsOfURL:location]];
//3
dispatch_async(dispatch_get_main_queue(), ^{
// do stuff with image
_imageWithBlock.image = downloadedImage;
});
}];
// 4
[getImageTask resume];
Delegates:
-----------
-(void)URLSession:(NSURLSession *)session
downloadTask:(NSURLSessionDownloadTask *)downloadTask
didFinishDownloadingToURL:(NSURL *)location
{
// use code above from completion handler
}
-(void)URLSession:(NSURLSession *)session
downloadTask:(NSURLSessionDownloadTask *)downloadTask
didWriteData:(int64_t)bytesWritten
totalBytesWritten:(int64_t)totalBytesWritten
totalBytesExpectedToWrite:(int64_t)totalBytesExpectedToWrite
{
NSLog(@"%f / %f", (double)totalBytesWritten,
(double)totalBytesExpectedToWrite);
}
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