How to programmatically add a proxy to an NSURLSession

Question

Looking over the documentation of NSURLSession and NSURLSessionConfiguration, I was under the impression I should configure it with a dictionary like the following:

    // Create a dictionary to describe the proxy 
    NSDictionary *proxyDict = @{
        (NSString *)kCFProxyHostNameKey   : @"myProxyHost.com",
        (NSString *)kCFProxyPortNumberKey : @"12345",
        (NSString *)kCFProxyTypeKey       : (NSString*)kCFProxyTypeHTTP
    };

    // Create a configuration that uses the dictionary
    NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
    [configuration setConnectionProxyDictionary:proxyDict];

However, the requests from NSURLSession created with this configuration connect directly.

Answer 1

It turns out, the dictionary keys you want are the Stream variants, they are the ones that resolve down to "HTTPProxy" and such:

NSString* proxyHost = @"myProxyHost.com";
NSNumber* proxyPort = [NSNumber numberWithInt: 12345];

// Create an NSURLSessionConfiguration that uses the proxy
NSDictionary *proxyDict = @{
    @"HTTPEnable"  : [NSNumber numberWithInt:1],
    (NSString *)kCFStreamPropertyHTTPProxyHost  : proxyHost,
    (NSString *)kCFStreamPropertyHTTPProxyPort  : proxyPort,

    @"HTTPSEnable" : [NSNumber numberWithInt:1],
    (NSString *)kCFStreamPropertyHTTPSProxyHost : proxyHost,
    (NSString *)kCFStreamPropertyHTTPSProxyPort : proxyPort,
};

NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration ephemeralSessionConfiguration];
configuration.connectionProxyDictionary = proxyDict;

// Create a NSURLSession with our proxy aware configuration
NSURLSession *session = [NSURLSession sessionWithConfiguration:configuration delegate:self delegateQueue:[NSOperationQueue mainQueue]];

// Form the request
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"https://www.google.com?2"]];

// Dispatch the request on our custom configured session
NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:
                              ^(NSData *data, NSURLResponse *response, NSError *error) {
                                  NSLog(@"NSURLSession got the response [%@]", response);
                                  NSLog(@"NSURLSession got the data [%@]", data);
                              }];

NSLog(@"Lets fire up the task!");
[task resume];