Important note if your project doesn’t use ARC: you must add the -fobjc-arc compiler flag to SVHTTPRequest.m in Target Settings > Build Phases > Compile Sources.

SVHTTPRequest

SVHTTPRequest is a simple and extremely straightforward way to communicate with RESTful web APIs for iOS and Mac. It’s a simpler and cleaner alternative to bulky ASIHTTPRequest, AFNetworking and RESTKit. It is blocked-based, uses NSURLConnection, ARC, as well as NSJSONSerialization to automatically parse JSON responses (making it only compatible with iOS 5 and Mac OS X Lion).

SVHTTPRequest features:

• straightforward singleton convenience methods for making GET, POST, PUT, DELETE, HEAD and download requests.
• completion block handler returning response (NSObject if JSON, otherwise NSData), NSHTTPURLResponse and NSError objects.
• persistent basePath and basic authentication signing when using SVHTTPClient.
• support for multipart/form-data parameters in POST and PUT requests.
• talks with the network activity indicator (iOS only).

Installation

• Drag the SVHTTPRequest/SVHTTPRequest folder into your project.
• #import "SVHTTPRequest.h" (this will import SVHTTPClient as well)

Usage

(see sample Xcode project in /Demo)

The easiest way to make a request is using the SVHTTPRequest convenience methods:

[SVHTTPRequest GET:@"https://api.github.com/repos/samvermette/SVHTTPRequest"
        parameters:nil
        completion:^(id response, NSHTTPURLResponse *urlResponse, NSError *error) {
            watchersLabel.text = [NSString stringWithFormat:@"SVHTTPRequest has %@ watchers", [response valueForKey:@"watchers"]];
        }];

If most of your requests are made to the same API endpoint, you should instead use SVHTTPClient so you can set parameters (basePath, cachePolicy, sendParametersAsJSON, "userAgent) that will be used for each request:

[[SVHTTPClient sharedClient] setBasePath:@"http://api.twitter.com/1/"];

[[SVHTTPClient sharedClient] GET:@"users/show.json"
                      parameters:[NSDictionary dictionaryWithObject:@"samvermette" forKey:@"screen_name"]
                      completion:^(id response, NSHTTPURLResponse *urlResponse, NSError *error) {
                          followersLabel.text = [NSString stringWithFormat:@"@samvermette has %@ followers", [response valueForKey:@"followers_count"]];
                      }];

You can have mutiple SVHTTPClient instances using the sharedClientWithIdentifier: method.

If you would like to set those properties on individual requests, you’ll need to alloc/init the request, set the attributes, and then call start:

SVHTTPRequest *request = [[SVHTTPRequest alloc] initWithAddress:@"http://github.com/api/v2/json/repos/show/samvermette/SVHTTPRequest"
                                                         method:SVHTTPRequestMethodGET 
                                                     parameters:nil 
                                                     completion:^(id response, NSHTTPURLResponse *urlResponse, NSError *error) {
                                                         watchersLabel.text = [NSString stringWithFormat:@"SVHTTPRequest has %@ watchers", [[response valueForKey:@"repository"] valueForKey:@"watchers"]];
                                                     }];
request.cachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
[request start];

Making a download request

You can tell SVHTTPRequest to save a GET response directly to disk and track the progress along the way:

[SVHTTPRequest GET:@"http://example.com/db.sqlite.zip" 
        parameters:nil 
        saveToPath:[[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:@"store.zip"]
          progress:^(float progress) {
              progressLabel.text = [NSString stringWithFormat:@"Downloading (%.0f%%)", progress*100];
          } 
        completion:^(id response, NSHTTPURLResponse *urlResponse, NSError *error) {
            progressLabel.text = @"Download complete";
            // process file
        }];

Cancelling requests

Make sure you cancel requests for which the user isn’t waiting on anymore:

SVHTTPRequest *request = [SVHTTPRequest GET:@"http://api.twitter.com/1/users/show.json"
                                 parameters:[NSDictionary dictionaryWithObject:@"samvermette" forKey:@"screen_name"]
                                 completion:^(id response, NSHTTPURLResponse *urlResponse, NSError *error) {
                                     NSLog(@"%@", response);
                                 }];
   
[request cancel];

If you’re using SVHTTPClient, you can do that by calling cancelRequestsWithPath: or cancelAllRequests.

Disabling logging

By default, SVHTTPRequest will log messages to the console every time a request is made. You can disable this by adding the compiler flag -DSVHTTPREQUEST_DISABLE_LOGGING to SVHTTPRequest.m in Target Settings > Build Phases.

Under the hood

All SVHTTPRequest requests are made asynchronously using NSURLConnection’s built-in asynchronous methods. The completion block, however, is executed on the main thread. You should dispatch it to a separate thread/queue if it’s resource intensive enough that it hogs the main thread. This can be done easily using Grand Central Dispatch:

completion:^(id response, NSHTTPURLResponse *urlResponse, NSError *error) {
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
        // cpu-intensive code
    });
}];

Credits

SVHTTPRequest is brought to you by Sam Vermette and contributors to the project. If you have feature suggestions or bug reports, feel free to help out by sending pull requests or by creating new issues. If you’re using SVHTTPRequest in your project, attribution would be nice.