Remove a notification if its event has been redacted.

ElementX/Sources/Other/Extensions/UNNotificationContent.swift

@@ -44,6 +44,10 @@ extension UNNotificationContent {
     @objc var roomID: String? {
         userInfo[NotificationConstants.UserInfoKey.roomIdentifier] as? String
     }
+
+    @objc var eventID: String? {
+        userInfo[NotificationConstants.UserInfoKey.eventIdentifier] as? String
+    }
 }
 
 extension UNMutableNotificationContent {
@@ -64,6 +68,15 @@ extension UNMutableNotificationContent {
             userInfo[NotificationConstants.UserInfoKey.roomIdentifier] = newValue
         }
     }
+
+    override var eventID: String? {
+        get {
+            userInfo[NotificationConstants.UserInfoKey.eventIdentifier] as? String
+        }
+        set {
+            userInfo[NotificationConstants.UserInfoKey.eventIdentifier] = newValue
+        }
+    }
 
     func addMediaAttachment(using mediaProvider: MediaProviderProtocol?,
                             mediaSource: MediaSourceProxy) async -> UNMutableNotificationContent {

NSE/Sources/NotificationContentBuilder.swift

@@ -63,6 +63,10 @@ struct NotificationContentBuilder {
         let notification = UNMutableNotificationContent()
         notification.receiverID = notificationItem.receiverID
         notification.roomID = notificationItem.roomID
+        notification.eventID = switch notificationItem.event {
+        case .timeline(let event): event.eventId()
+        case .invite, .none: nil
+        }
         notification.sound = notificationItem.isNoisy ? UNNotificationSound(named: UNNotificationSoundName(rawValue: "message.caf")) : nil
         // So that the UI groups notification that are received for the same room but also for the same user
         // Removing the @ fixes an iOS bug where the notification crashes if the mute button is tapped

NSE/Sources/NotificationServiceExtension.swift

@@ -59,8 +59,8 @@ class NotificationServiceExtension: UNNotificationServiceExtension {
     override func didReceive(_ request: UNNotificationRequest,
                              withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
         guard !DataProtectionManager.isDeviceLockedAfterReboot(containerURL: URL.appGroupContainerDirectory),
-              let roomId = request.roomId,
-              let eventId = request.eventId,
+              let roomID = request.roomID,
+              let eventID = request.eventID,
               let clientID = request.pusherNotificationClientIdentifier,
               let credentials = keychainController.restorationTokens().first(where: { $0.restorationToken.pusherNotificationClientIdentifier == clientID }) else {
             // We cannot process this notification, it might be due to one of these:
@@ -103,8 +103,8 @@ class NotificationServiceExtension: UNNotificationServiceExtension {
 
         Task {
             await run(with: credentials,
-                      roomId: roomId,
-                      eventId: eventId,
+                      roomID: roomID,
+                      eventID: eventID,
                       unreadCount: request.unreadCount)
         }
     }
@@ -117,18 +117,18 @@ class NotificationServiceExtension: UNNotificationServiceExtension {
     }
 
     private func run(with credentials: KeychainCredentials,
-                     roomId: String,
-                     eventId: String,
+                     roomID: String,
+                     eventID: String,
                      unreadCount: Int?) async {
-        MXLog.info("\(tag) run with roomId: \(roomId), eventId: \(eventId)")
+        MXLog.info("\(tag) run with roomId: \(roomID), eventId: \(eventID)")
 
         guard let userSession = Self.userSession else {
             MXLog.error("Invalid NSE User Session, discarding.")
             return discard(unreadCount: unreadCount)
         }
 
         do {
-            guard let itemProxy = await userSession.notificationItemProxy(roomID: roomId, eventID: eventId) else {
+            guard let itemProxy = await userSession.notificationItemProxy(roomID: roomID, eventID: eventID) else {
                 MXLog.info("\(tag) no notification for the event, discard")
                 return discard(unreadCount: unreadCount)
             }
@@ -137,6 +137,10 @@ class NotificationServiceExtension: UNNotificationServiceExtension {
                 return discard(unreadCount: unreadCount)
             }
 
+            if await handleRedactionNotification(itemProxy) {
+                return discard(unreadCount: unreadCount)
+            }
+
             // After the first processing, update the modified content
             modifiedContent = try await notificationContentBuilder.content(for: itemProxy, mediaProvider: nil)
 
@@ -246,6 +250,29 @@ class NotificationServiceExtension: UNNotificationServiceExtension {
 
         return false
     }
+
+    /// Handles a notification for an `m.room.redaction` event.
+    /// - Returns: A boolean indicating whether the notification was handled.
+    private func handleRedactionNotification(_ itemProxy: NotificationItemProxyProtocol) async -> Bool {
+        guard case let .timeline(event) = itemProxy.event,
+              case let .messageLike(content) = try? event.eventType(),
+              case let .roomRedaction(redactedEventID, _) = content else {
+            return false
+        }
+
+        guard let redactedEventID else {
+            MXLog.error("Unable to redact notification due to missing event ID.")
+            return true // Return true as there's no point showing this notification.
+        }
+
+        let deliveredNotifications = await UNUserNotificationCenter.current().deliveredNotifications()
+
+        if let targetNotification = deliveredNotifications.first(where: { $0.request.content.eventID == redactedEventID }) {
+            UNUserNotificationCenter.current().removeDeliveredNotifications(withIdentifiers: [targetNotification.request.identifier])
+        }
+
+        return true
+    }
 }
 
 // https://stackoverflow.com/a/77300959/730924

NSE/Sources/Other/UNNotificationRequest.swift

@@ -18,11 +18,11 @@ import Foundation
 import UserNotifications
 
 extension UNNotificationRequest {
-    var roomId: String? {
+    var roomID: String? {
         content.userInfo[NotificationConstants.UserInfoKey.roomIdentifier] as? String
     }
 
-    var eventId: String? {
+    var eventID: String? {
         content.userInfo[NotificationConstants.UserInfoKey.eventIdentifier] as? String
     }