Twilio Engage Plugin

• Twilio Engage Destination
  • Getting Started
  • Subscription
  • Predefined Actions
  • Default Notification Handling
  • Custom Notification Handling
  • Handling Media
    • Create Extension
    • Display Media
  • License

This plugin enables Segment's Analytics SDK to do push notification management with Twilio Engage.

Getting Started

To get started:

1. follow the set up instructions for Analytics Swift here to integrate Segment's Analytics SDK into your app.
2. add the dependency:

via Xcode

In the Xcode File menu, click Add Packages. You'll see a dialog where you can search for Swift packages. In the search field, enter the URL to this repo.

https://github.com/segment-integrations/analytics-swift-engage

You'll then have the option to pin to a version, or specific branch, as well as which project in your workspace to add it to. Once you've made your selections, click the Add Package button.

via Package.swift

Open your Package.swift file and add the following do your the dependencies section:

.package(
            name: "Segment",
            url: "https://github.com/segment-integrations/analytics-swift-engage.git",
            from: "1.1.2"
        ),

3. Import the Plugin in the file you configure your analytics instance:

import Segment
import TwilioEngage // <-- Add this line

4. Add an engage variable at the top of your ApplicationDelegate.

@main
class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterDelegate {
    let engage = TwilioEngage { previous, current in
        Tab1ViewController.addPush(s: "Push Status Changed = \(current)")
    }

5. Just under your Analytics-Swift library setup, call analytics.add(plugin: ...) to add an instance of the plugin to the Analytics timeline.

let analytics = Analytics(configuration: Configuration(writeKey: "<YOUR WRITE KEY>")
                    .flushAt(3)
                    .trackApplicationLifecycleEvents(true))

analytics.add(plugin: engage)

6. Add the Following methods to your AppDelegate in order to start receiving and handling notifications

AppDelegate

   func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {

    //add the following:

        let center  = UNUserNotificationCenter.current()
        center.delegate = self
        center.requestAuthorization(options: [.sound, .alert, .badge]) { (granted, error) in
            guard granted else {
                Analytics.main.declinedRemoteNotifications()
                Tab1ViewController.addPush(s: "User Declined Notifications")
                return
            }
            DispatchQueue.main.async {
                UIApplication.shared.registerForRemoteNotifications()
            }
        }
        
        //Necessary in older versions of iOS.
        if let notification = launchOptions?[UIApplication.LaunchOptionsKey.remoteNotification] as? [String: Codable] {
            Tab1ViewController.addPush(s: "App Launched via Notification \(notification)")
            Analytics.main.receivedRemoteNotification(userInfo: notification)
        }

        ...

        return true
}

func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
    //Segment event to register for remote notifications
    Analytics.main.registeredForRemoteNotifications(deviceToken: deviceToken)
}

func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
    //Segment event for failure to register for remote notifications
    Analytics.main.failedToRegisterForRemoteNotification(error: error)
}

    func userNotificationCenter(
        _ center: UNUserNotificationCenter,
        willPresent notification: UNNotification,
        withCompletionHandler completionHandler:
        @escaping (UNNotificationPresentationOptions) -> Void
    ) {
        Analytics.main.receivedRemoteNotification(userInfo: userInfo)
        
        completionHandler([.banner, .sound, .badge])
    }
    
    func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void)
    {
        Analytics.main.receivedRemoteNotification(userInfo: userInfo)
        
        completionHandler()
    }

Subscription

Once the plugin is setup, it automatically tracks and updates push notification subscriptions according to device's notification permissions. To listen to the subscription status changes, provide a StatusCallback when initialize the plugin as following:

let engage = TwilioEngage { previous, current in
    //handle status updates 
    print("Push Status Changed /(current)")
}

On iOS, three different statuses are tracked: Subscribed, DidNotSubscribe, Unsubscribed.

• Subscribed is reported whenever app user toggles their device settings to allow push notification
• DidNotSubscribe is reported in fresh start where no status has ever been reported
• Unsubscribed is reported whenever user toggles their device settings to disable push notification and when the SDK fails to obtain a token from APNS

Predefined Actions

Twilio Engage provides 4 predefined tapActions that you can handle however you see fit.

• open_app: the app opens to the main view when the notification/button is on tapped.
• open_url: the default browser opens a webview to the provided link
• deep_link: the application routes to the provided link
• <custom_action>: a custom string which can be handled much like a deep-link depending on the use case.

Default Notification Handling

How you implement your push notification set up is entirely up to you. If you would prefer a "standard" implementation you can follow the instructions in this section. The behavior of your notifications will follow the options outlined in the Predefined Actions section above. If you would prefer to handle notifications in your own way, refer to the following section, Custom Notification Handling.

1. Set the default notification categories inside the didFinishinLaunchingWithOptions method.

...
    
let center  = UNUserNotificationCenter.current()
center.delegate = self
        
//add default categories
let categories = engage.createDefaultCategories()
        
UNUserNotificationCenter.current()
    .setNotificationCategories()

Defining Custom Actions You can define custom actions/categories to work in addition to the default ones outlined in Predefined Actions.

let customCategory = TwilioEngage.CustomCategory(title: "customized_push", acceptActionTitle: "Accept Title", dismissActionTitle: "Dismiss Title")
        
let categories = engage.createDefaultCategories(customCategory: customCategory)

2. Add the handleNotification() method to the userNotificationCenter didReceive method.

func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void)
{
    let userInfo = response.notification.request.content.userInfo
    Analytics.main.receivedRemoteNotification(userInfo: userInfo)

    //engage method to handle default notifications 
    engage.handleNotificiation(response: response)
    completionHandler()
}

Use the Notification extension to listen for deep_links and custom_actions

Since it is not possible for the Twilio Engage plugin to automatically route deep-links or determine the logic of a custom action, t plugin includes a Notification extension you can use to listen for and handle these notification types. See the example app for a complete implementation.

Notification.Name.openButton.onPost { notification in
    guard let deeplink = notification.userInfo?["link"] as? String else {return}
    print("Deep-link value: \(deeplink)")
}

Custom Notification Handling

If you need more control over your notifications, you can implement the handling and displaying in any way you see fit. Your analytics events will still be tracked, provided you have followed the general implementation steps outlined above. Examples for each of the predefined tapActions can be found below:

AppDelegate

When a push is received by a device the data is available in userNotificationCenter: didReceive (recieved in background) and userNotificationCenter: willPresent (recieved in foreground) in your AppDelegate.

func userNotificationCenter(
    _ center: UNUserNotificationCenter,
    willPresent notification: UNNotification,
    withCompletionHandler completionHandler:
    @escaping (UNNotificationPresentationOptions) -> Void
) {
    let userInfo = notification.request.content.userInfo
    Tab1ViewController.addPush(s: "Received in foreground: \(userInfo)")
    Analytics.main.receivedRemoteNotification(userInfo: userInfo)
        completionHandler([.banner, .sound, .badge])
   }
    
func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: @escaping () -> Void)
{
    let userInfo = response.notification.request.content.userInfo
    Tab1ViewController.addPush(s: "Received in background: \(userInfo)")
    Analytics.main.receivedRemoteNotification(userInfo: userInfo)

    //add a custom method to handle the notification data 
    handleNotificiation(notification: userInfo, shouldAsk: true)
    
    completionHandler()
}
 ...

//an extension for logic for displaying different notification types: 
extension AppDelegate {

  //Handle the notification based on the `tapAction`
  func handleNotificiation(notification: [AnyHashable: Any], shouldAsk: Bool) {
    if let aps = notification["aps"] as? NSDictionary {
      if let tapAction = aps["category"] as? String {
        switch tapAction {
          case "open_url":
            //add functionality for displaying a webview or opening a default browser 
          case "deep_link":
            //add functionality for navigating to a specific screen in the app 
          case "<custom_action>":
            //handle a custom action like accept/decline or confirm/cancel  
          default:
            //this will catch `open_app` to open home screen
            return
        }
      }
    }
  }
}

Handling Media

If you would like to display media in your push notifications, you will need to add a NotificationService extension to your app. Reference Apple's documentation for a more detailed overview of UNNotificationServiceExtension.

Creating the Extension

1. in Xcode, go to File -> New -> Target

2. search for the Notification Service Extension

3. name the extension <YourAppName>NotificationService> and finish the creation process.
4. <YourAppName>NotificationService/NotificationService> is where you can add custom logic to handle and display media.

Displaying Media

NotificationService didRecieve example

    override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
        self.contentHandler = contentHandler
        bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)
        
        if let bestAttemptContent = bestAttemptContent {
            var urlString: String? = nil
            let mediaArray: NSArray = bestAttemptContent.userInfo["media"] as! NSArray
            
            if let mediaURLString = mediaArray[0] as? String {
                urlString = mediaURLString
            }
            
            if urlString != nil, let fileURL = URL(string: urlString!){
                
                guard let mediaData = NSData(contentsOf: fileURL) else {
                    contentHandler(bestAttemptContent)
                    return
                }
                
                guard let mediaAttachment = UNNotificationAttachment.saveImageToDisk(fileIdentifier: "engage-image.png", data: mediaData, options: nil) else {
                    contentHandler(bestAttemptContent)
                    return
                }
                
                bestAttemptContent.attachments = [ mediaAttachment ]
            }
            contentHandler(bestAttemptContent)
        }
        
    }

...

//add an extension to `UNNotificationAttachment` to download/save the image 
@available(iOSApplicationExtension 10.0, *)
extension UNNotificationAttachment {
    
    static func saveImageToDisk(fileIdentifier: String, data: NSData, options: [NSObject : AnyObject]?) -> UNNotificationAttachment? {
        let fileManager = FileManager.default
        let folderName = ProcessInfo.processInfo.globallyUniqueString
        let folderURL = NSURL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(folderName, isDirectory: true)
        
        do {
            try fileManager.createDirectory(at: folderURL!, withIntermediateDirectories: true, attributes: nil)
            let fileURL = folderURL?.appendingPathComponent(fileIdentifier)
            try data.write(to: fileURL!, options: [])
            let attachment = try UNNotificationAttachment(identifier: fileIdentifier, url: fileURL!, options: options)
            return attachment
        } catch let error {
            print("error \(error)")
        }
        
        return nil
    }
}

License

MIT License

Copyright (c) 2021 Segment

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.