APNS

a gem for the Apple Push Notification Service.

Install

sudo gem install apns

Setup:

Convert your certificate

In Keychain access export your certificate as a p12. Then run the following command to convert it to a .pem

  
    openssl pkcs12 -in cert.p12 -out cert.pem -nodes -clcerts
  

After you have your .pem file. Set what host, port, certificate file location on the APNS class:

  
    APNS.host = 'gateway.push.apple.com' 
    # gateway.sandbox.push.apple.com is default

    APNS.pem  = '/path/to/pem/file'
    # this is the file you just created
    
    APNS.port = 2195 
    # this is also the default. Shouldn't ever have to set this, but just in case Apple goes crazy, you can.
  

Example (Single notification):

Then to send a push notification you can either just send a string as the alert or give it a hash for the alert, badge and sound.

  
    device_token = '123abc456def'

    APNS.send_notification(device_token, 'Hello iPhone!' )

    APNS.send_notification(device_token, :alert => 'Hello iPhone!', :badge => 1, :sound => 'default')
  

Example (Multiple notifications):

You can also send multiple notifications using the same connection to Apple:

  
    device_token = '123abc456def'

    n1 = APNS::Notification.new(device_token, 'Hello iPhone!' )

    n2 = APNS::Notification.new(device_token, :alert => 'Hello iPhone!', :badge => 1, :sound => 'default')
    
    APNS.send_notifications([n1, n2])
  

Send other info along with aps

You can send other application specific information as well.

  
    APNS.send_notification(device_token, :alert => 'Hello iPhone!', :badge => 1, :sound => 'default',
                                         :other => {:sent => 'with apns gem'})
  

This will add the other hash to the same level as the aps hash:

  
    {"aps":{"alert":"Hello iPhone!","badge":1,"sound":"default"},"sent":"with apns gem"}
  

Getting your iPhone’s device token

After you setup push notification for your application with Apple. You need to ask Apple for you application specific device token.

ApplicationAppDelegate.m

  
    - (void)applicationDidFinishLaunching:(UIApplication *)application 
    {    
        // Register with apple that this app will use push notification
        [[UIApplication sharedApplication] registerForRemoteNotificationTypes:(UIRemoteNotificationTypeAlert | 
          UIRemoteNotificationTypeSound | UIRemoteNotificationTypeBadge)];

        // Your app startup logic...
        return YES;
    }

    - (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken 
    {
        // Convert the binary data token into an NSString (see below for the implementation of this function)
        NSString *deviceTokenAsString = stringFromDeviceTokenData(deviceToken);

        // Show the device token obtained from apple to the log
        NSLog(@"deviceToken: %@", deviceTokenAsString);
    }
  

stringFromDeviceTokenData function

This snippet comes from this stackoverflow post’s anwser.

  
    NSString* stringFromDeviceTokenData(NSData *deviceToken)
    {
      const char *data = [deviceToken bytes];
      NSMutableString* token = [NSMutableString string];

for (int i = 0; i < [deviceToken length]; i++) {
[token appendFormat:@"%02.2hhX", data[i]];
}

return [[token copy] autorelease];
}

For more information on Apple Push Notifications you can see Apple Developer Documentation here.