android - Firebase Cloud Messaging - How to validate Tokens?

Question

I am using Firebase Cloud Messaging (FCM) and as per the abreviated code below everytime a new Token is generated on the Customer Device... I send this new TOKEN to my SERVER DB (Cloud) where I save it in order to be able to send future Push Notification from the Server to the Device using the CFM API.

    //public class CFMInstanceIDService extends FirebaseInstanceIdService ...

    public void onTokenRefresh() {
        ...
        String cfmToken = FirebaseInstanceId.getInstance().getToken();        
        ...     
        sendRegistrationToServer(customerGuid, cfmToken);
    }

By doing this I have on the Server a list of ALL (multiples) Devices where a Customer is logged-in. (Tablet, Phone, iPhone, Android, etc)

Is there any way to verify/validate a Token at any time?

I would like to know/ensure that all the tokens that I have associated to a Customer belong to real Devices. I don't want to send Push Notifications to not-existing Tokens.

Answer 1

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