Push notifications allow software applications to deliver messages and notifications to users without requiring the user to actively check for updates. Push notifications can contain data, notifications, or both. There are two main platforms for delivering push notifications: Firebase Cloud Messaging (FCM) for Android and Apple Push Notification Service (APNs) for iOS. Both support delivering notifications via HTTP and XMPP/MQTT protocols. iOS 10 introduced enhancements like rich notifications that allow images, videos, and interactive buttons in notifications. It also introduced notification extensions that give developers more control over customizing notification content.

1. 06.12.2016
Recep Düzdemir | Software Infrastructure
Gizem Akman | Software Infrastructure
Push Notification

2. Push Notification
 Push notification is the delivery of information
from a software application to a computing
device without a specific request from
the client.
 Message may contain notification, data or
both.

4. Push Notification Lifecycle
Register
Store Registration Token
Send Message

5. Message Parameters

6. Message Parameters (Cont’d)

7. Message Payload

8. Notification Parameters

9. Firebase Cloud Messaging
• HTTP API
• XMPP API

10. FCM HTTP API
• @ https://gcm-http.googleapis.com/gcm/send
• syncronous
• supports multiple recipients and topics
• no delivery receipt
• unidirectional

11. FCM HTTP Response Codes

12. FCM HTTP Errors

13. FCM HTTP Errors (Cont’d)

14. FCM HTTP Errors (Cont’d)

15. FCM XMPP API
• @ fcm-xmpp.googleapis.com:5235
• asyncronous
• supports single recipient only
• bidirectional
• returns delivery receipt

16. FCM XMPP Errors

17. FCM XMPP Errors (Cont’d)

18. FCM XMPP Errors (Cont’d)

19. Apple Push Notification Service (APNs)
• Legacy API ( TCP)
• HTTP/2 API

20. APNs Binary API
• @gateway.push.apple.com:2195
• supports up to 2KB payload
• separate feedback service @ feedback.push.apple.com:2196
• returns no response in case of success
• returns an error response in case of failure and immediately
closes the connection

21. APNs Binary API Response Format

22. APNs HTTP/2 API
• @api.push.apple.com:443
• supports up to 4KB payload

23. APNs HTTP/2 Response Format

24. APNs HTTP/2 Error Reasons

25. APNs HTTP/2 Error Reasons (Cont’d)

26. iOS vs Android

27. Q&A

29. IOS 10 RICH NOTIFICATIONS
 In iOS 10 notifications are becoming a key part
of Apple's mobile operating system, and one
of the primary way that users interact with
apps.

30. IOS 10 RICH NOTIFICATIONS
 As part of the new UserNotifications framework, Apple has
given us the ability to make notifications that contain
images, sound, video, or even custom content generated on
the device.
 Much of this capability comes via three new features
showcased at Worldwide Developers Conference(WWDC):
media attachments, notification service extensions, and
notification content extensions.
 Including media in your push notification can increase the
open rate.

31. What’s new in iOS 10
Notifications?
 Notifications can now contain images and gifs

32. What’s new in iOS 10
Notifications?
 It is now possible to add images and gifs to
notifications.
 These images or gifs can be loaded either from
the resources of your app, or from a remote URL.
 iOS will first download the image or gif and then
display the notification.

33. What’s new in iOS 10
Notifications?
 Notifications can contain
videos
 Notifications can contain
videos up to 50 megabytes
in size.

34. What’s new in iOS 10
Notifications?
 Notifications can be
interactive
 Notifications can now contain buttons.
Users can use action buttons to interact
with notifications.
 As with earlier versions of iOS, buttons
can also be used to open your app and
take specific actions. But unlike earlier
versions, actions buttons are much more
easily seen since they don't require a left-
swipe on the notification.

35. Why Media Attachments Are
Awesome
 Media attachments open up new opportunities for
user engagement with our apps.
 Before, we were limited to just a couple lines of text;
we had to rely on the user opening the app to do
anything more.
 This is a win-win for app makers and users. App makers
get to deliver more compelling content in their
notifications, and users get more choice in their level of
notification interaction.

36. How They Work
 Media attachments work slightly different between
local notifications and remote notifications.
 In the case of a local notification, its media attachment
must contain the URL of a file on disk at the time that
an app creates the notification.
 The file is copied when the notification is scheduled,
and that file is delivered along with the notification. No
extra effort is required.

37. How They Work
 For a remote notification, a remote notification service delivers
information about the media attachment as part of the APNS
notification payload.
 This includes the attachment URL, which, importantly, does not
have to be the URL of a file already on the device.
 However, iOS 10 will not automatically deliver an attachment with a
notification if that attachment is not stored locally.
 Apple’s solution to this problem is something called the
Notification Service Extension.

38. Notification Service Extension
 Before IOS 10

39. Notification Service Extension
 IOS 10

40. Notification Service Extension
 Service extension lets you customize the
content of a remote notification before it is
delivered to the user.
 You could use the extension to decrypt an
encrypted data block or to download images
associated with the notification.

41. Notification Service Extension
 At 4KB in size, a remote notification’s payload is too
small to deliver a media attachment file itself.
 Instead, we define an attachment URL in the remote
notification payload.
 Once a device receives the remote notification payload
for our app, the app’s service extension gets the
chance to download the file at the URL and attach it to
the notification before the device displays the
notification to the user.

42. Notification Service Extension
 How to add service extension to your
application?

43. Notification Service Extension
 Add a new target to your project

44. Notification Service Extension
When you created the Service Extension, Xcode created the NotificationService.swift file
and an Info.plist file.

45. Notification Service Extension
 We use the first function to download the content from the
URL and add it to the notification. We should also handle
network errors here.
 We use the second function to handle the case where the
first function runs out of time (as determined by iOS).

46. Notification Service Extension
How does iOS know which
notifications to intercept?

47. Notification Service Extension
 Notification Payload
 The mutable-content fields tells iOS that the notification has
content that can be changed by a service extension before delivery

48.  What if we don’t just want to serve up simple
media files?
 What if we want to generate custom content?

49. Notification Content Extension
 Notification Content Extension let you provide
custom UI for your notifications.
 A Notification Content Extension gives us a
chance to process a notification and supply
new content to the notification before it is
displayed to the user.

50. Notification Content Extension
Most important things:
 Custom views
 Support for remote and local notifications
 No interaction with views (possible only with
notification actions)
 Respond to notification actions

51. Notification Content Extension
 How to add content extension to your
application?

52. Notification Content Extension
 Add a new target to your project

53. Notification Content Extension
MainInterface.storyboard : we will desing our notification UI in this.
NotificationViewController.swift : a UIViewController subclass that will
enable us to update our custom interface.
When you created the Content Extension, Xcode created
the NotificationViewController.swift file, a MainInterface.storyboard file and
an Info.plist file.

54. Notification Content Extension
 How does the notification content extension
work?

55. Notification Content Extension
 Set an identifier for UNNotificationExtensionCategory key in
extension's Info.plist:

56. Notification Content Extension
 Remote Notifications
 Local Notifications
{
aps: {
category: ‘myNotificationCategory'
}
}

57. Notification Content Extension

58. Notification Content Extension
 We may also implement optional functions
that handle action button presses or display
media playback controls.
 How to add a custom action?

59. Notification Actions
 You can add up to four actions and each
action is encompassed in a ‘category’.

60.  Demo

61. Android N Notifications
 Notifications are become an important part of
every Android application and it is an
intelligent way to re-engage users with the
installed apps.
 Effectively used notifications will help
application to get returning users.

62. Android N Notifications
 To provide a better user experience,
notifications on Android N have received a
visual refresh, improved support for custom
views, and expanded functionality in the
forms of Direct Reply, a new MessagingStyle,
and bundled notifications.

63. Android N Notifications
 The first and most obvious change is that the default look
and feel of notifications has significantly changed.
 Many of the fields that were spread around the
notifications have been collapsed into a new header row
with your app’s icon and name anchoring the notification.
 This change ensured that the title, text, and large icon are
given the most amount of space possible and, as a result,
notifications are generally slightly larger now and easier to
read.

64. Android N Notifications

65. Android N Notifications
 Notification actions have also received a
redesign and are now in a visually separate
bar below the notification.

66. Direct Reply
 While notification actions have already been
able to launch an Activity or do background
work with a Service or BroadcastReceiver,
Direct Reply allows you to build an action that
directly receives text input inline with the
notification actions.

67. Direct Reply

68. Android N Notifications
 If you’re building a messaging app and expect
back and forth conversations, you should use
MessagingStyle and append the additional
message to it.

69. Messaging Style

70. Messaging Style

71. Bundled Notifications
 Bundled
notifications
that appear
grouped
when a
group ID has
been set for
each
notification.

72. Bundled Notifications
 We can also
display
actions for
notifications
that are
bundled.

73. Custom View Notifications
 We can now
use custom
views for
notifications
These can
be for both
collapsed
and
expanded
notification
layouts.

74.  Demo

75. Q&A