Firebase cloud function error code and error message is always Internal on Android

Question

I'm developing a feature for my app, where one user can send a notification to another user using cloud functions. My functions and my notifications work as expected, but I'm not able to handle errors in a proper way, because I always get "INTERNAL" as the error on my Android code.

Here is my code for Android:

public static Task<String> callFirebaseFunction(HashMap<String, Object> data, String funcion){

    FirebaseFunctions mFunctions = FirebaseFunctions.getInstance();

    return mFunctions
        .getHttpsCallable(funcion)
        .call(data)
        .continueWith(new Continuation<HttpsCallableResult, String>() {
            @Override
            public String then(@NonNull Task<HttpsCallableResult> task) throws Exception {
                return (String) task.getResult().getData();
            }
        });
}

Here is where I call callFirebaseFunction

Utilities.callFirebaseFunction(dataNoty, nombreFuncion)
    .addOnCompleteListener(new OnCompleteListener<String>() {
        @Override
        public void onComplete(@NonNull Task<String> task) {
            if ( !task.isSuccessful() ){
                Exception e = task.getException();
                if (e instanceof FirebaseFunctionsException) {
                    FirebaseFunctionsException ffe = (FirebaseFunctionsException) e;
                    FirebaseFunctionsException.Code code = ffe.getCode(); // It's always INTERNAL
                    Object details = ffe.getMessage(); // It's always INTERNAL
                } else {
                    // handle error
                }
            } else {
                // success
            }
        }
    });

And here is my code for my cloud function

exports.helloWorld = functions.https.onRequest((req, res) => {
    let data     = req.body.data;
    let id = data['id'].toString();
    db.collection('users').doc(id).get()
        .then((snapshot) => {
            let infoUser = snapshot.data();
            // Verifies data
            if ( typeof infoUser !== "undefined" && Object.keys(infoUser).length > 0 ){
                // Some code
            } else {
                throw new functions.https.HttpsError(
                    'invalid-argument',             // code
                    'Error',                        // message
                    'User ' + id + ' not found'     // details
                );
            }
        }).then( () => {
            console.log('Success');
            return res.status(200).send("success");
        }).catch( error => {
            res.status(500).send(error.details);
            return new functions.https.HttpsError(error.code, error.details);
        });
});

I've tried different versions of code in my catch segment, for example:

.catch( error => {
    res.status(500).send('Error');
    throw new functions.https.HttpsError('invalid-argument', 'Error');
});

I don't know how am I supposed to make my catch segment, and I really need to get the error I throw in node (not just "INTERNAL").

Answer 1

Callable functions require the following format:

exports.yourFunction = functions.https.onCall((data, context) => {
  // ...
});

It is not the same thing as an HTTP triggered Cloud Function, which is what you're using. You can still access it using an HTTP request from your Android app, but if you want to use mFunctions.getHttpsCallable(function).call(data), you will need to use a Callable Cloud Function, which I linked above.