APNS Firebase Notification failed to fetch token

Question

For Swift3 / iOS10 see this link:

ios10, Swift 3 and Firebase Push Notifications (FCM)

I'm trying to use the Firebase for Notifications and I integrated it exactly as described in the docs. But I don't understand why is doesn't work. When I build my project I see this line:

2016-05-25 16:09:34.987: <FIRInstanceID/WARNING> Failed to fetch default token Error Domain=com.firebase.iid Code=0 "(null)"

This my AppDelegate:

 func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    FIRApp.configure()
    FIRDatabase.database().persistenceEnabled = true
     var service: DataService = DataService()
    service.start()
    registerForPushNotifications(application)
    application.registerForRemoteNotifications()
    return true
}

func registerForPushNotifications(application: UIApplication) {
    let notificationSettings = UIUserNotificationSettings(
        forTypes: [.Badge, .Sound, .Alert], categories: nil)
    application.registerUserNotificationSettings(notificationSettings)
}

func application(application: UIApplication, didRegisterUserNotificationSettings notificationSettings: UIUserNotificationSettings) {
    if notificationSettings.types != .None {
        application.registerForRemoteNotifications()
    }
}

func application(application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: NSData) {
    let tokenChars = UnsafePointer<CChar>(deviceToken.bytes)
    var tokenString = ""

    for i in 0..<deviceToken.length {
        tokenString += String(format: "%02.2hhx", arguments: [tokenChars[i]])
    }

    FIRInstanceID.instanceID().setAPNSToken(deviceToken, type: FIRInstanceIDAPNSTokenType.Unknown)
    print("Device Token:", tokenString)
}
func application(application: UIApplication, didReceiveRemoteNotification userInfo: [NSObject : AnyObject], fetchCompletionHandler completionHandler: (UIBackgroundFetchResult) -> Void)  {
    // Print message ID.
    print("Message ID: \(userInfo["gcm.message_id"]!)")

    // Print full message.
    print("%@", userInfo)
}

Answer 1

1.Set Notification Observer in didFinishLaunchingWithOptions Method

2.And Set tokenRefreshNotification method then u get Token in this method.

See below Code

import Firebase
import FirebaseMessaging

override func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
  FIRApp.configure()

      NotificationCenter.default.addObserver(self,
                                                     selector: #selector(self.tokenRefreshNotification(notification:)),
                                                     name: NSNotification.Name.firInstanceIDTokenRefresh,
                                                     object: nil)
}

// NOTE: Need to use this when swizzling is disabled
public func application(application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: NSData) {

  FIRInstanceID.instanceID().setAPNSToken(deviceToken, type: FIRInstanceIDAPNSTokenType.Sandbox)
}

func tokenRefreshNotification(notification: NSNotification) {
  // NOTE: It can be nil here
  let refreshedToken = FIRInstanceID.instanceID().token()
  print("InstanceID token: \(refreshedToken)")

  connectToFcm()
}

func connectToFcm() {
  FIRMessaging.messaging().connectWithCompletion { (error) in
    if (error != nil) {
      print("Unable to connect with FCM. \(error)")
    } else {
      print("Connected to FCM.")
    }
  }
}

public func application(application: UIApplication, didReceiveRemoteNotification userInfo: [NSObject : AnyObject]) {
  print(userInfo)
}