hawkinchina / https-github.com-tolo-HHServices

HHServices (also known as Hejsan-Hoppsan-Services)

This little project came about when we wanted to upgrade two of our apps, PlayMeNext & PlayMyQ, to use some nifty new iOS5 features, just to be rudely awakened by the fact that bluetooth networking via NSNetService was no longer possible. So what to do? Well, the only option seemed to be to go low-level and dive right down into the DNSService* (dns-sd) APIs. This is the result. And to spare others from having to take this low-level road, I decided to share it with those having the same problem/need.

This framework may not be perfect and it doesn't do everything that NSNetService does, but it handles the most important stuff and hopefully it can be of some use to you too. Enjoy.

Usage examples

Publish service

NSUInteger serverPort;

// Setup your server (maybe using something like GCDAsyncSocket or CocoaHTTPServer etc)
...

// Setup the service publisher - remember to update the type parameter with your actual service type
publisher = [[HHServicePublisher alloc] initWithName:@"MyDisplayName"
                                type:@"_myexampleservice._tcp." domain:@"local." txtData:nil port:serverPort];
publisher.delegate = self;
[publisher beginPublish];

Discover service

// Browse for services - make sure you set the type parameter to your service type
browser = [[HHServiceBrowser alloc] initWithType:@"_myexampleservice._tcp." domain:@"local."];
browser.delegate = self;
[browser beginBrowse];

Resolve service

- (void) serviceBrowser:(HHServiceBrowser*)serviceBrowser didFindService:(HHService*)service moreComing:(BOOL)moreComing {
    ...
    service.delegate = self;
    [service beginResolve];
    // Make sure you retain the service object (for instance add it to a list of services currently 
    // being resolved), otherwise it will be deallocated upon return of this method.
    ...
}

- (void) serviceDidResolve:(HHService*)service {
	...
	NSArray* rawAddresses = service.resolvedAddresses;
    for (NSData* addressData in rawAddresses) {
        struct sockaddr* address = (struct sockaddr*)[addressData bytes];
	    
        // Create yourself a nice little socket. For example if you're using HTTP, set up 
        // the connection using for example ASIHTTPRequest or AFNetworking. Or if you 
        // want to use a custom TCP protocol, have a look GCDAsyncSocket or roll your own 
        // with something this:
        CFSocketSignature signature;
        signature.protocolFamily = PF_INET;
        signature.socketType = SOCK_STREAM;
        signature.protocol = IPPROTO_TCP;
        signature.address = CFDataCreate(kCFAllocatorDefault, (const UInt8*)address, address->sa_len);
        CFReadStreamRef readStream;
        CFWriteStreamRef writeStream;
        CFStreamCreatePairWithPeerSocketSignature(kCFAllocatorDefault, &signature, &readStream, &writeStream);
	
        NSInputStream *inputStream = (NSInputStream *)readStream;
        NSOutputStream *outputStream = (NSOutputStream *)writeStream;
        [inputStream setDelegate:self];
        [outputStream setDelegate:self];
        [inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
        [outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
        [inputStream open];
        [outputStream open];
        ...
    }
	...
}