Firebase Functions, Response in not a valid json object

Question

i am developing a role-based application using android studio, since my project needs admin rights for creating user and deleting user i used firebase admin sdk for my project. I tried to delete multiple accounts but i faced with issue. The response returns not a valid json object. As in my code i tried to handle possible errors. However the response still returns not a valid json object. See below

index.js

    exports.deleteUser = functions.https.onCall(async (data,context) => {
try {
    if(!context.auth) {
        throw new AuthenticationError('Kimlik Doğrulaması Yapılmamış');
    }
    const uids = JSON.parse(data);
    console.log(uids);
    const callerUid = context.auth.uid;
    const callerUser = await admin.auth().getUser(callerUid);
    if(!callerUser.customClaims.admin && !callerUser.customClaims.superadmin) {
        throw new NotAnAdminError('Bu işlemi sadece yöneticiler gerçekleştirebilir');
    } 
    const reference = admin.firestore().collection("Users");
    const res = await admin.auth().deleteUsers(uids);
    res.errors.forEach(element => console.log(element));
    const successes = res.successCount;
    const fails = res.failureCount;
    console.log(fails);
    console.log(successes);
    if(fails===0) {
        await uids.forEach(element => reference.doc(element).delete());
        return {result:successes+' Öğrenci Silindi!'};
    }else {
        throw new functions.https.HttpsError('Silme Hatası','Bilinmeyen hata, 
        silinemeyen öğrenci sayısı: '+fails);
    }
}
    catch(error) {
        if(error.type === 'NotAnAdminError') {
            throw new functions.https.HttpsError('Bu işlemi yapma yetkiniz 
             yok.',error.message);
        }else if(error.type === 'AuthenticationError') {
            throw new functions.https.HttpsError('Kimlik Hatası',error.message);
        }else {
            throw new functions.https.HttpsError('internal ERROR from catch 
            block',error.message);
        }
     }
});

Android Code

    private Task<String> deleteUsers(List<CheckableUser> users) {
    List<String> idlist = new ArrayList<>();
    for (CheckableUser user:users) {
        idlist.add(user.getUid());
    }
    return mFunctions.getHttpsCallable("deleteUsers").call(jsonFormatted).
    continueWith(new Continuation<HttpsCallableResult, String>() {
        @Override
        public String then(@NonNull Task<HttpsCallableResult> task) throws Exception {               
        HashMap<String,Object> data = task.getResult().getData();
        String result = data.get("result");
        Log.d(TAG, "then: "+result);
        return result;
        }
    });
mFunctions.getHttpsCallable("deleteUsers").call(jsonFormatted).continueWith(new 
Continuation<HttpsCallableResult, String>() {
        @Override
        public String then(@NonNull Task<HttpsCallableResult> task) throws Exception {
            HashMap<String,Object> data = task.getResult().getData();
            String result = data.get("result");
            Log.d(TAG, "then: "+result);
            return result;
        }
    });
}


deleteUsers(users).addOnCompleteListener(new OnCompleteListener<String>() {
                        @Override
                        public void onComplete(@NonNull Task<String> task) {
                            if (task.isSuccessful()) {
                                Snackbar snackbar = 
Snackbar.make(requireView().findViewById(R.id.constraintlayout),"Selected users are 
deleted",4000);
                                snackbar.show();
                            }else {
                                debugFirebase(task.getException());
                            }
                        }
                    });


private void debugFirebase(Exception e) {
    if (e instanceof FirebaseFunctionsException) {
        FirebaseFunctionsException ffe = (FirebaseFunctionsException) e;
        Log.d(TAG, "debugFirebase: MESSAGE: "+ffe.getMessage());
        Log.d(TAG, "debugFirebase: CODE: "+ffe.getCode());
        Log.d(TAG, "debugFirebase: DETAILS: "+ffe.getDetails());
        Log.e(TAG, "debugFirebase: EXCEPTION: ",ffe );
    }
}

Exception

com.google.firebase.functions.FirebaseFunctionsException: Response is not valid 
JSONobject.
Caused by: org.json.JSONException: Value <!DOCTYPE of type java.lang.String cannot be 
converted to JSONObject

Answer 1

Your function is declared and exported as "deleteUser", but you are calling it in the Android client as "deleteUsers", which is not the same. The strings need to match.