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Handle invalid token responses in FCM

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#1,064 3 comments 3 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
30/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
java
Domain
backend-api-design

Research direction

Start with the linked Firebase token-management documentation and trace how IncomingHttpResponse becomes a FirebaseMessagingException. Compare the UNREGISTERED and INVALID_ARGUMENT responses in the issue, then determine how completion should distinguish invalid registration tokens from other INVALID_ARGUMENT failures without relying on message strings.

Written by the indexing model from the issue text.

Description

api: messaging type: feature request

As per the documentation a token could be invalid if you have two error codes:

  • UNREGISTERED (HTTP 404)
  • INVALID_ARGUMENT (HTTP 400)

However INVALID_ARGUMENTS can be caused by other errors.

At the moment we receive the content below from the IncomingHttpResponse which is also the error message from the FirebaseMessagingException. What we do is to check the string of the message in order to delete these tokens.

Content: {
  "error": {
    "code": 400,
    "message": "The registration token is not a valid FCM registration token",
    "status": "INVALID_ARGUMENT",
    "details": [
      {
        "@type": "type.googleapis.com/google.firebase.fcm.v1.FcmError",
        "errorCode": "INVALID_ARGUMENT"
      }
    ]
  }
}

What is the proper way to handle these errors?
Does it make sense to update FirebaseMessagingException to provide more information about which field is invalid or perhaps have a new error code - INVALID_TOKEN? This would remove a lot of unambiguity as to when it is needed to manage the token.

Dominant language
Java
Stars
620
Forks
305
Avg merge
3h 23m
Merged PRs (30d)
1

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Open the contributing guide

First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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