JTV-APNS

Jtv-apns is a gem for accessing the Apple Push Notification Service that allows
both sending notifications and reading from apple’s feedback service. This gem
is based heavily on the work of James Pozdena (http://github.com/jpoz/APNS).

sudo gem install jtv-apns

First, you will need to export your development/production iphone push service
certificate and key from your keychain. To do this select the private key and
certificate, and select File → Export from your keychain. By default a .p12
file will be generated containing certificate and key.

Next, run the following command to convert this .p12 file into a .pem file.

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

This pem file should be stored somewhere secure that your application can access. Next, set the jtv-apns configuration parameters:

###################
# Hosts Config
###################

# Push Notification Service:
#
# (default: gateway.sandbox.push.apple.com is)
# Set as below for a production install
APNS.host = 'gateway.push.apple.com' 

# (default: 2195)
# APNS.port = 2195

# Feedback Service:
#
# (default: feedback.sandbox.push.apple.com)
APNS.feedback_host = 'feedback.push.apple.com'

# (default: 2196)
# APNS.feedback_port = 2196

####################
# Certificate Setup
####################

# Path to the .pem file created earlier
APNS.pem  = '/path/to/pem/file'

# Password for decrypting the .pem file, if one was used
APNS.pass = 'xxxx'

####################
# Connection Mgmt
####################

# Cache open connections when sending push notifications
# this will force the gem to keep 1 connection open per
# host/port pair, and reuse it when sending notifications

# (default: false)
# APNS.cache_connections = true

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, :aps => {:alert => 'Hello iPhone!', :badge => 1, :sound => 'default'})

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

device_token = '123abc456def'

n1 = [device_token, :aps => { :alert => 'Hello...', :badge => 1, :sound => 'default' }
n2 = [device_token, :aps => { :alert => '... iPhone!', :badge => 1, :sound => 'default' }]

APNS.send_notifications([n1, n2])

Application-specific information can be included along with the alert by
passing it along with the “aps” key in the message hash.

APNS.send_notification(device_token, :aps => { :alert => 'Hello iPhone!', :badge => 1, :sound => 'default'},
                                     :sent_by => 'Justin.tv')

If connection caching is enabled, you can tell the gem to establish connections before sending any notifications.

APNS.establish_notification_connection
# ...
if APNS.has_notification_connection?
  APNS.send_notification(device_token, "It works!")
end

jtv-apns provides a simple api to access Apple’s feedback service. Below is an example for setting the feedback time on an ActiveRecord object corresponding to a device token.

# APNS.feedback_each returns an array of Hash objects with the following keys
# :feedback_on => (Time) Time Apple considers app unregistered from device
# :length => (Fixnum) Length of :device_token, currently always 32 (bytes)
# :device_token => (String) hex-encoded device token
APNS.feedback.each do |feedback|
  d = RegisteredDevices.find(:first, :conditions => { :device_token = feedback.device_token })
  unless d.nil?
    d.feedback_on = feedback.feedback_on
  end
end

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)];	

}

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken {

    // Show the device token obtained from apple to the log

    NSLog("deviceToken: %", deviceToken);

}