--- name: capacitor-push-notifications description: Complete guide to implementing push notifications in Capacitor apps using Firebase Cloud Messaging (FCM) and Apple Push Notification Service (APNs). Covers setup, handling, and best practices. Use this skill when users need to add push notifications. --- # Push Notifications in Capacitor Implement push notifications for iOS and Android using Firebase and APNs. ## When to Use This Skill - User wants push notifications - User needs FCM setup - User asks about APNs - User has notification issues - User wants rich notifications ## Quick Start ### Install Plugin ```bash bun add @capacitor/push-notifications bunx cap sync ``` ### Basic Implementation ```typescript import { PushNotifications } from '@capacitor/push-notifications'; async function initPushNotifications() { // Request permission const permission = await PushNotifications.requestPermissions(); if (permission.receive === 'granted') { // Register for push await PushNotifications.register(); } // Get FCM token PushNotifications.addListener('registration', (token) => { console.log('Push token:', token.value); // Send token to your server sendTokenToServer(token.value); }); // Handle registration error PushNotifications.addListener('registrationError', (error) => { console.error('Registration error:', error); }); // Handle incoming notification (foreground) PushNotifications.addListener('pushNotificationReceived', (notification) => { console.log('Notification received:', notification); // Show in-app notification showInAppNotification(notification); }); // Handle notification tap PushNotifications.addListener('pushNotificationActionPerformed', (action) => { console.log('Notification action:', action); // Navigate based on notification data handleNotificationTap(action.notification); }); } ``` ## Firebase Setup ### 1. Create Firebase Project 1. Go to https://console.firebase.google.com 2. Create new project 3. Add iOS and Android apps ### 2. Android Configuration Download `google-services.json` to `android/app/` ```groovy // android/build.gradle buildscript { dependencies { classpath 'com.google.gms:google-services:4.4.0' } } ``` ```groovy // android/app/build.gradle apply plugin: 'com.google.gms.google-services' dependencies { implementation platform('com.google.firebase:firebase-bom:32.7.0') implementation 'com.google.firebase:firebase-messaging' } ``` ### 3. iOS Configuration Download `GoogleService-Info.plist` to `ios/App/App/` ```ruby # ios/App/Podfile pod 'Firebase/Messaging' ``` ```swift // ios/App/App/AppDelegate.swift import Firebase import FirebaseMessaging @UIApplicationMain class AppDelegate: UIResponder, UIApplicationDelegate { func application( _ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? ) -> Bool { FirebaseApp.configure() return true } func application( _ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data ) { Messaging.messaging().apnsToken = deviceToken } } ``` ### 4. iOS Capabilities In Xcode: 1. Select App target 2. Signing & Capabilities 3. Add "Push Notifications" 4. Add "Background Modes" > "Remote notifications" ## APNs Key Setup (iOS) ### Create APNs Key 1. Go to https://developer.apple.com/account 2. Certificates, IDs & Profiles 3. Keys > Create Key 4. Enable Apple Push Notifications service (APNs) 5. Download .p8 file ### Add to Firebase 1. Firebase Console > Project Settings 2. Cloud Messaging tab 3. iOS app configuration 4. Upload APNs Authentication Key (.p8) 5. Enter Key ID and Team ID ## Sending Notifications ### Firebase Admin SDK (Node.js) ```typescript import admin from 'firebase-admin'; // Initialize admin.initializeApp({ credential: admin.credential.cert(serviceAccount), }); // Send to single device async function sendToDevice(token: string) { await admin.messaging().send({ token, notification: { title: 'Hello!', body: 'You have a new message', }, data: { type: 'message', messageId: '123', }, android: { priority: 'high', notification: { channelId: 'messages', icon: 'ic_notification', color: '#4285f4', }, }, apns: { payload: { aps: { badge: 1, sound: 'default', }, }, }, }); } // Send to topic async function sendToTopic(topic: string) { await admin.messaging().send({ topic, notification: { title: 'Breaking News', body: 'Something important happened', }, }); } // Send to multiple devices async function sendToMultiple(tokens: string[]) { await admin.messaging().sendEachForMulticast({ tokens, notification: { title: 'Update', body: 'New features available', }, }); } ``` ### HTTP v1 API ```bash curl -X POST \ 'https://fcm.googleapis.com/v1/projects/YOUR_PROJECT/messages:send' \ -H 'Authorization: Bearer ACCESS_TOKEN' \ -H 'Content-Type: application/json' \ -d '{ "message": { "token": "DEVICE_TOKEN", "notification": { "title": "Hello", "body": "World" } } }' ``` ## Advanced Features ### Notification Channels (Android) ```typescript import { PushNotifications } from '@capacitor/push-notifications'; // Create channel await PushNotifications.createChannel({ id: 'messages', name: 'Messages', description: 'Message notifications', importance: 5, // Max importance visibility: 1, // Public sound: 'notification.wav', vibration: true, lights: true, lightColor: '#FF0000', }); // Delete channel await PushNotifications.deleteChannel({ id: 'old-channel' }); // List channels const channels = await PushNotifications.listChannels(); ``` ### Topic Subscription ```typescript // Subscribe to topic await PushNotifications.addListener('registration', async () => { // Subscribe to topics based on user preferences const messaging = getMessaging(); await subscribeToTopic(messaging, 'news'); await subscribeToTopic(messaging, 'promotions'); }); ``` ### Rich Notifications (iOS) ```swift // ios/App/NotificationService/NotificationService.swift import UserNotifications class NotificationService: UNNotificationServiceExtension { override func didReceive( _ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void ) { guard let mutableContent = request.content.mutableCopy() as? UNMutableNotificationContent else { contentHandler(request.content) return } // Add image if let imageUrl = request.content.userInfo["image"] as? String, let url = URL(string: imageUrl) { downloadImage(url: url) { attachment in if let attachment = attachment { mutableContent.attachments = [attachment] } contentHandler(mutableContent) } } else { contentHandler(mutableContent) } } } ``` ### Notification Actions ```typescript // Handle action buttons PushNotifications.addListener('pushNotificationActionPerformed', (action) => { switch (action.actionId) { case 'reply': // Handle reply action const input = action.inputValue; sendReply(input); break; case 'dismiss': // Handle dismiss break; default: // Handle tap navigateToContent(action.notification.data); } }); ``` ## Background Handling ### Data-Only Notifications ```typescript // Server-side: Send data-only message { "to": "DEVICE_TOKEN", "data": { "type": "sync", "action": "refresh" } // No "notification" key = data-only } ``` ```kotlin // android/app/src/main/java/.../FirebaseService.kt class FirebaseService : FirebaseMessagingService() { override fun onMessageReceived(message: RemoteMessage) { // Handle data message in background message.data["type"]?.let { type -> when (type) { "sync" -> performBackgroundSync() "update" -> checkForUpdates() } } } } ``` ## Local Notifications Fallback ```typescript import { LocalNotifications } from '@capacitor/local-notifications'; // Show local notification when in foreground PushNotifications.addListener('pushNotificationReceived', async (notification) => { await LocalNotifications.schedule({ notifications: [ { id: Date.now(), title: notification.title || '', body: notification.body || '', extra: notification.data, }, ], }); }); ``` ## Best Practices ### Permission Handling ```typescript async function requestNotificationPermission() { const { receive } = await PushNotifications.checkPermissions(); if (receive === 'prompt') { // Show explanation first const shouldRequest = await showPermissionExplanation(); if (shouldRequest) { const result = await PushNotifications.requestPermissions(); return result.receive === 'granted'; } return false; } if (receive === 'denied') { // Guide user to settings showSettingsPrompt(); return false; } return receive === 'granted'; } ``` ### Token Refresh ```typescript // Handle token refresh PushNotifications.addListener('registration', async (token) => { const oldToken = await getStoredToken(); if (oldToken !== token.value) { // Token changed, update server await updateServerToken(oldToken, token.value); await storeToken(token.value); } }); ``` ### Error Handling ```typescript PushNotifications.addListener('registrationError', (error) => { console.error('Push registration failed:', error); // Log to analytics analytics.logEvent('push_registration_failed', { error: error.error, }); // Retry with backoff scheduleRetry(); }); ``` ## Troubleshooting ### iOS Not Receiving 1. Check APNs key in Firebase 2. Verify Push Notifications capability 3. Check provisioning profile 4. Verify device token format 5. Test with Firebase Console ### Android Not Receiving 1. Verify google-services.json 2. Check notification channel exists 3. Verify FCM token 4. Check battery optimization 5. Test with Firebase Console ### Common Issues | Issue | Solution | |-------|----------| | No token | Check permissions, network | | Foreground only | Implement background handler | | Delayed delivery | Use high priority, data-only | | No sound | Configure notification channel | | Badge not updating | Set badge in payload | ## Resources - Capacitor Push Notifications: https://capacitorjs.com/docs/apis/push-notifications - Firebase Cloud Messaging: https://firebase.google.com/docs/cloud-messaging - APNs Documentation: https://developer.apple.com/documentation/usernotifications