Getting error while fetching FCM key from Firebase cloud messaging

Question

Am trying to fetch the FCM key for push notification from Firebase cloud messaging but am getting nil & error which I mention below

** Error:- APNS device token not set before retrieving FCM Token for Sender ID '836092823410'. Notifications to this FCM Token will not be delivered over APNS. Be sure to re-retrieve the FCM token once the APNS device token is set. **

Google Plist File

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">

<plist version="1.0">

<dict>

    <key>CLIENT_ID</key>

    <string>836092823410-d76r5bkjrusfmgo6rskqo81l4mk7vmp4.apps.googleusercontent.com</string>

    <key>REVERSED_CLIENT_ID</key>

    <string>com.googleusercontent.apps.836092823410-d76r5bkjrusfmgo6rskqo81l4mk7vmp4</string>

    <key>API_KEY</key>

    <string>AIzaSyDpP1n_NRqj9c_Mq-pA2PlRez7AnVM5buw</string>

    <key>GCM_SENDER_ID</key>

    <string>836092823410</string>

    <key>PLIST_VERSION</key>

    <string>1</string>

    <key>BUNDLE_ID</key>

    <string>com.iai.tracker</string>

    <key>PROJECT_ID</key>

    <string>crucial-audio-334611</string>

    <key>STORAGE_BUCKET</key>

    <string>crucial-audio-334611.appspot.com</string>

    <key>IS_ADS_ENABLED</key>

    <false/>

    <key>IS_ANALYTICS_ENABLED</key>

    <false/>

    <key>IS_APPINVITE_ENABLED</key>

    <true/>

    <key>IS_GCM_ENABLED</key>

    <true/>

    <key>IS_SIGNIN_ENABLED</key>

    <true/>

    <key>GOOGLE_APP_ID</key>

    <string>1:836092823410:ios:0312dc35c45b23b9e37feb</string>

</dict>

</plist>

Delegate File

import UIKit
import GoogleMaps
import Firebase
import GooglePlaces
import Highcharts

enum BuildTypes: String {
    case jsd = "JSD"
    case fleetPolice = "FleetPolice"
    case veyron = "Veyron"
    case jbd = "JBD"
    case gpsTracker = "GPSTracker"
    case roadLookUp = "RoadLookUp"
    case iaitrack = "IAITrack"
}

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, MessagingDelegate {

    var window: UIWindow?

    let gcmMessageIDKey = "gcm.message_id";

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        
        //Going through different build type
        let buildType: String = Bundle.main.infoDictionary?["BUILD_TYPE"] as? String ?? "Debug"
        print("Build type: - ",buildType)
        
        NotificationCenter.default.addObserver(self, selector: #selector(self.notAuthorized), name: HTTPUtil.NotAuthorizedNotification, object: nil);
        
        switch buildType {
        case BuildTypes.jsd.rawValue, BuildTypes.fleetPolice.rawValue:
            print("JSD")
            GMSServices.provideAPIKey("AIzaSyBKsjff4VNWTyu8X3UTYXOBazO0jt_Cnpw");
            GMSPlacesClient.provideAPIKey("AIzaSyBKsjff4VNWTyu8X3UTYXOBazO0jt_Cnpw");
        case BuildTypes.veyron.rawValue, BuildTypes.jbd.rawValue, BuildTypes.gpsTracker.rawValue:
            GMSServices.provideAPIKey("AIzaSyCRWtSQIUsoNhFwMMdeFRX0A74rooHskBg");
            GMSPlacesClient.provideAPIKey("AIzaSyCRWtSQIUsoNhFwMMdeFRX0A74rooHskBg");
        case BuildTypes.iaitrack.rawValue:
            GMSServices.provideAPIKey("AIzaSyC2qDNCajLm1Kq_AuZTS5tE0xJ73R1RTkA");
            GMSPlacesClient.provideAPIKey("AIzaSyC2qDNCajLm1Kq_AuZTS5tE0xJ73R1RTkA");
        default:
            print("REst")
            GMSServices.provideAPIKey("AIzaSyAgaZm9nk4RcfgZ0O0R9UgxJ7PRLZt0RB4");
            GMSPlacesClient.provideAPIKey("AIzaSyAgaZm9nk4RcfgZ0O0R9UgxJ7PRLZt0RB4");
        }
        
        FirebaseApp.configure()
        Messaging.messaging().delegate = self
        let t = Messaging.messaging().token { token, error in
            if (token != nil) {
                print(token)
            } else {
                print(error)
            }
        }
        let token = Messaging.messaging().fcmToken
            print("FCM token: \(token ?? "")")
        if #available(iOS 10.0, *) {
            // For iOS 10 display notification (sent via APNS)
            UNUserNotificationCenter.current().delegate = self
            
            let authOptions: UNAuthorizationOptions = [.alert, .badge, .sound]
            UNUserNotificationCenter.current().requestAuthorization(
                options: authOptions,
                completionHandler: {_, _ in })
        } else {
            let settings: UIUserNotificationSettings =
                UIUserNotificationSettings(types: [.alert, .badge, .sound], categories: nil)
            application.registerUserNotificationSettings(settings)
        }
        
        application.registerForRemoteNotifications()
        
        
        HIChartView.preload()
        
        let u = UserService.getActiveUserLocalCache();
        Configuration.setBaseUrl(baseUrl: u?.baseUrl ?? "https://api.fleethunt.in/");
        
        return true
    }
    
    func messaging(_ messaging: Messaging, didReceiveRegistrationToken fcmToken: String?) {
        debugPrint(fcmToken);
    }
    
    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any]) {
        // If you are receiving a notification message while your app is in the background,
        // this callback will not be fired till the user taps on the notification launching the application.
        // TODO: Handle data of notification
        
        // With swizzling disabled you must let Messaging know about the message, for Analytics
        // Messaging.messaging().appDidReceiveMessage(userInfo)
        
        // Print message ID.
        if let messageID = userInfo[gcmMessageIDKey] {
            print("Message ID: \(messageID)")
        }
        
        // Print full message.
        print(userInfo)
    }
    
    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any],
                     fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
        // If you are receiving a notification message while your app is in the background,
        // this callback will not be fired till the user taps on the notification launching the application.
        // TODO: Handle data of notification
        
        // With swizzling disabled you must let Messaging know about the message, for Analytics
        // Messaging.messaging().appDidReceiveMessage(userInfo)
        
        // Print message ID.
        if let messageID = userInfo[gcmMessageIDKey] {
            print("Message ID: \(messageID)")
        }
        
        // Print full message.
        print(userInfo)
        
        completionHandler(UIBackgroundFetchResult.newData)
    }
    
    @objc func notAuthorized(){
        if let window = self.window{
            let mainTabController = window.rootViewController as! MainTabBarController;
            mainTabController.selectedIndex = 0;
            let home = (mainTabController.viewControllers?[0] as! UINavigationController).viewControllers[0] as! HomeViewController;
            home.showLoginVC();
            window.makeToast("Not Authorized. You have been logged out");
        }
    }

    
    
    func applicationWillResignActive(_ application: UIApplication) {
        // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
        // Use this method to pause ongoing tasks, disable timers, and invalidate graphics rendering callbacks. Games should use this method to pause the game.
    }

    func applicationDidEnterBackground(_ application: UIApplication) {
        // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
        // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
    }

    func applicationWillEnterForeground(_ application: UIApplication) {
        // Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
        self.updateFcmToken();
        
        let u = UserService.getActiveUserLocalCache();
        Configuration.setBaseUrl(baseUrl: u?.baseUrl ?? "https://api.fleethunt.in/");
    }

    func applicationDidBecomeActive(_ application: UIApplication) {
        // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
    }

    func applicationWillTerminate(_ application: UIApplication) {
        // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    }

    
    // This function is added here only for debugging purposes, and can be removed if swizzling is enabled.
    // If swizzling is disabled then this function must be implemented so that the APNs token can be paired to
    // the FCM registration token.
    func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        
        self.updateFcmToken();
        
        // With swizzling disabled you must set the APNs token here.
        // Messaging.messaging().apnsToken = deviceToken
    }
    
    func updateFcmToken() -> Void{
        let mute =  UserDefaults.standard.bool(forKey: "mute") ?? false
        print(mute);
        FCMService.updateFCM(mute: mute) { (resp) in
        
        }
    }
    
    var orientationLock = UIInterfaceOrientationMask.portrait
    func application(_ application: UIApplication, supportedInterfaceOrientationsFor window: UIWindow?) -> UIInterfaceOrientationMask {
        return self.orientationLock
    }
    
    struct AppUtility {
        static func lockOrientation(_ orientation: UIInterfaceOrientationMask) {
            if let delegate = UIApplication.shared.delegate as? AppDelegate {
                delegate.orientationLock = orientation
            }
        }
        
        static func lockOrientation(_ orientation: UIInterfaceOrientationMask, andRotateTo rotateOrientation:UIInterfaceOrientation) {
            self.lockOrientation(orientation)
            UIDevice.current.setValue(rotateOrientation.rawValue, forKey: "orientation")
        }
    }
    
}
@available(iOS 10, *)
extension AppDelegate : UNUserNotificationCenterDelegate {
    // [START refresh_token]
    func messaging(_ messaging: Messaging, didRefreshRegistrationToken fcmToken: String) {
        print("Firebase registration token: \(fcmToken)")
        self.updateFcmToken();
    }
    // [END refresh_token]
    
    // [START ios_10_data_message]
    // Receive data messages on iOS 10+ directly from FCM (bypassing APNs) when the app is in the foreground.
    // To enable direct data messages, you can set Messaging.messaging().shouldEstablishDirectChannel to true.
    func messaging(_ messaging: Messaging, didReceive remoteMessage: MessagingDelegate) {
        print("Received data message: \(remoteMessage.description)")
    }
    // [END ios_10_data_message]
    // Receive displayed notifications for iOS 10 devices.
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                                willPresent notification: UNNotification,
                                withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        let userInfo = notification.request.content.userInfo
        
        // With swizzling disabled you must let Messaging know about the message, for Analytics
        // Messaging.messaging().appDidReceiveMessage(userInfo)
        
        // Print message ID.
        if let messageID = userInfo[gcmMessageIDKey] {
            print("Message ID: \(messageID)")
        }
        
        // Print full message.
        print(userInfo)
        
        // Change this to your preferred presentation option
        completionHandler([])
    }
    
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                                didReceive response: UNNotificationResponse,
                                withCompletionHandler completionHandler: @escaping () -> Void) {
        let userInfo = response.notification.request.content.userInfo
        // Print message ID.
        if let messageID = userInfo[gcmMessageIDKey] {
            print("Message ID: \(messageID)")
        }
        
        // Print full message.
        print(userInfo)
        
        completionHandler()
    }
}

Answer 1

This is my Appdelegate extension and it works:

import UIKit
import Firebase


extension AppDelegate {
    func setupFirebase(application: UIApplication) {
        
        FirebaseApp.configure()
        FirebaseConfiguration.shared.setLoggerLevel(.min)
        Messaging.messaging().delegate = self
        Messaging.messaging().token { token, error in
          if let error = error {
            print("Error fetching FCM registration token: \(error)")
          } else if let token = token {
            print("FCM registration token: \(token)")
          }
        }
        
        UNUserNotificationCenter.current().delegate = self
        
        let authOptions: UNAuthorizationOptions = [.alert, .badge, .sound]
        UNUserNotificationCenter.current().requestAuthorization(
            options: authOptions,
            completionHandler: {_, _ in })
        
        application.registerForRemoteNotifications()
    }
    // [START receive_message]
    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any]) {
        
    }
    
    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any],
                     fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {
        completionHandler(UIBackgroundFetchResult.newData)
    }
    // [END receive_message]
    func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
    }
    
    func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        print("APNs token retrieved: \(deviceToken)")
        UserDefaults.standard.set(deviceToken, forKey: APNS_TOKEN)
        Messaging.messaging().apnsToken = deviceToken
    }
}

extension AppDelegate : UNUserNotificationCenterDelegate {
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                                willPresent notification: UNNotification,
                                withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        let userInfo = notification.request.content.userInfo
        if let messageID = userInfo[fcmMessageIDKey] {
            print("Message ID: \(messageID)")
        }
        print(userInfo)
        completionHandler([[.alert, .sound]])
    }
    
    func userNotificationCenter(_ center: UNUserNotificationCenter,
                                didReceive response: UNNotificationResponse,
                                withCompletionHandler completionHandler: @escaping () -> Void) {
        let userInfo = response.notification.request.content.userInfo
        if let messageID = userInfo[fcmMessageIDKey] {
            print("Message ID: \(messageID)")
        }
        print(userInfo)
        
        completionHandler()
    }
}

extension AppDelegate : MessagingDelegate {
    // [START refresh_token]
    func messaging(_ messaging: Messaging, didReceiveRegistrationToken fcmToken: String?) {
        print("Firebase registration token: \(String(describing: fcmToken))")

        if let _fcmToken = fcmToken {
            UserDefaults.standard.set(_fcmToken, forKey: FCM_TOKEN)
          
            let dataDict:[String: String] = ["token": _fcmToken]
            NotificationCenter.default.post(name: Notification.Name("FCMToken"), object: nil, userInfo: dataDict)
        }
        
    }
}

you can call in "didFinishLaunchingWithOptions"

setupFirebase(application: application)