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

Answer 1

The answers above cover most of the issue, but I had the same issue and I found the following info useful:

1. Firebase can 'rotate' (change) a user's FCM token at any time. This is the 128 character ID that your server will use to send the push notification to the device.

2. Firebase docs say best practice is to use a delegate to monitor for changes with the delegate callback method:

   - (void)messaging:(nonnull FIRMessaging *)messaging didRefreshRegistrationToken:(nonnull NSString *)fcmToken
   

[Obj - C]

func messaging(_ messaging: Messaging, didRefreshRegistrationToken fcmToken: String)

[Swift]

The delegate method should be called on every change, at which point you can update the record in your server.

3. Unfortunately that wasn't working for me, I had a delegate but the callback wasn't being invoked. So I had to resort to manually updating the token on each app launch (as suggested by @micheal chein above) as follows:

   NSString *deviceToken = [FIRInstanceID instanceID].token; // Send this to your server
   

   [Obj-C]

   let token = FIRInstanceID.instanceID().token() // Send this to your server
   

   [Swift]

** Important: update the token after a delay (20-25s), as the rotation can sometimes only reflect after some time. You can use a timer for this.

4. After this I still get the APNS warning/error message:

   2017-06-06 09:21:49.520:  Failed to fetch APNS token Error Domain=com.firebase.iid Code=1001 "(null)"
   

BUT, push notifications work every time without fail. So I think that log message is a bit off (possibly mistimed). If you can get option 2 to work for you, definitely do that!