More verbose error message

[Real-Gecko]

I had a misconfigured APNS on FCM and was receiving InvalidArgumentError('Request contains an invalid argument.') from fcm-django while trying to send message to iOS, which was totally unclear to me. By using debugger I was able to find that exact response from FCM is

{
    "error": {
        "code": 400,
        "message": "Request contains an invalid argument.",
        "status": "INVALID_ARGUMENT",
        "details": [
            {
                "@type": "type.googleapis.com/google.firebase.fcm.v1.FcmError",
                "errorCode": "INVALID_ARGUMENT"
            },
            {
                "@type": "type.googleapis.com/google.firebase.fcm.v1.ApnsError",
                "statusCode": 400,
                "reason": "DeviceTokenNotForTopic"
            }
        ]
    }
}

Which showed that problem is in APNS actually with certain error reason. Is it possible to get more verbose error output without using debugger?

[eliezerp3]

Did u ever get post v1 fcm-django to work for iOS?

[Real-Gecko]

Yes it's working now, there was some kind of configuration issue in Firebase related to APNS certificates and developer key, which I'm not aware of cause Firebase setup and iOS development is done by other people. However this reason DeviceTokenNotForTopic was a key to solving this, and INVALID_ARGUMENT was not clear to anyone. That's why I created this issue.

[Real-Gecko]

By the way, to actually get notification on iOS(actual popup) you need to send notification like this:

    message = Message(data=data, notification=Notification(title=title, body=body))

As Android developers said to me it's it's only sufficient to have data with title and body keys, but for iOS you need actual Notification instance added to the message.

[xtrinch]

@Real-Gecko Did the error messages not write itself onto the devices, visible in the admin panel?

[Real-Gecko]

Did not check that, because I don't use admin. But only message I got is mentioned in op.