AWS SNS (Push)

Overview

• Supports Mobile and Web push notifications
• Opt-in
  • Not required by SNS (unlike other subscription types)
  • Required by OS (iOS, Android, Kindle Fire)

Mobile Push notifications

• Appears on mobile device (notification)
• Device must have an app installed
• Received even if the app is not running
• When you click on such notification the app is typically started on mobile device
• Cheaper than SMS and better experience
• Each installed app must be registered with SNS
• Examples: Pingdom alerts, HipChat notifications

Web Push notifications

• Notification displayed by the browser
• Supported by most major browsers

Push Notification Service (PNS)

• Platforms
• • Apple Push Notification Service (APNS)
  • Google Cloud Messaging for Android (GCM)
  • Amazon Device Messaging (ADM)
  • Windows Push Notification Service (WNS) for Windows Phone 8+ and 8.1+
  • Microsoft Push Notification Service (MPNS) for Windows Phone 7+
  • Baidu Cloud Push for Android in China
• PNS maintains connection with app@device
• AWS object ("Application") must be created for each platform
• • CreatePlatformApplication
  • • PlatformPrincipal
    • PlatformCredentials

Device Token 

• Created by PNS 
• Alternative names
• • Registration Id
• App receives it when it registers itself with PNS
• App must send it to the Publisher system (i.e. "our server")
• • POST to Proxy server
  • Cognito - registers directly with SNS
•  Publisher registers app@device with SNS
• • CreatePlatformEndpoint
• can be subscribed to any number of topics
• can be target of direct publish (aka "direct addressing")
• it is like "phone number" in SMS
• Registering existing device token with SNS
• • AWS Console (single)
  • CreatePlatformEndpoint (several)
  • AWS Console CSV (bulk)

PNS Device Token Feedback

• Similar to email "hard-bounce" 
• SNS automatically handles it
• • Disables the endpoint and notifies about the event
  • GCM returns new token: SNS updates existing

TTL

• useful for time-sensitive messages
• how much time in seconds PNS has to deliver the message 
• • e.g. drop if device is turned-off
  • relative to Publish time
• dwell time
• • time between publish and hand-off to PNS
• Default: 4 weeks
• 0 value - if no special meaning for PNS - drop the message

Delivery Status

• Collect feedback on successful and unsuccessful delivery attempts
• Specify separate IAM roles for success/failure
• Specify sampling rate (0,100)
• AWS writes to CloudWatch Logs
• • Create Metrics/Filters

References

• https://caniuse.com/#feat=push-api