Delete a specific user from Firebase

Question

Is there a way I can get a specific user account from firebase and then delete it?

For instance:

// I need a means of getting a specific auth user.
var user = firebase.auth().getUser(uid);
// Note the getUser function is not an actual function.

After, I want to delete that user and their additional data:

// This works
user.delete().then(function() {
   // User deleted.
   var ref = firebase.database().ref(
      "users/".concat(user.uid, "/")
   );
   ref.remove();
});

Firebase Documentation states that users can be deleted if they are currently logged in:

firebase.auth().currentUser.delete()

My aim is to allow logged in admin user to delete other users from the system.

Answer 1

When using the client-side SDKs for Firebase Authentication, you can only delete the user account that is currently signed in. Anything else would be a huge security risk, as it would allow users of your app to delete each other's account.

The Admin SDKs for Firebase Authentication are designed to be used in a trusted environment, such as your development machine, a server that you control, or Cloud Functions. Because they run in a trusted environment, they can perform certain operations that the client-side SDKs can't perform, such as deleting user accounts by simply knowing their UID.

Also see:

• delete firebase authenticated user from web application

---

Another common approach is to keep a allowlist/blocklist in for example the Firebase Database and authorize user based on that. See How to disable Signup in Firebase 3.x

Answer 2

You definitely don't want to use firebase-admin in your application itself, as I think was suggested by Ali Haider, since it needs a private key which you don't want to deploy with your code.

You can however create a Cloud Function in Firebase that triggers on the deletion of a user in your Firestore or Realtime database and let that Cloud Function use firebase-admin to delete the user. In my case I have a collection of users in my Firestore with the same userid's as created by Firebase Auth, in which I save extra user data like the name and the role etc.

If you're using Firestore as me, you can do the following. If you're using Realtime database, just look up in the documentation how to use a trigger for that.

1. Make sure your Firebase project has cloud functions initialized. There should be a folder named 'functions' in your project directory. If not: initialize Cloud Functions for your project with the following command: firebase init functions.

2. Obtain a private key for your service account in the Firebase Console on the following page: Settings > Service accounts.

3. Place the json-file containing the private key in the functions\src folder next to the index.ts file.

4. Export the following function in index.ts:

export const removeUser = functions.firestore.document("/users/{uid}")
    .onDelete((snapshot, context) => {        
        const serviceAccount = require('path/to/serviceAccountKey.json');
        admin.initializeApp({
            credential: admin.credential.cert(serviceAccount),
            databaseURL: "https://<DATABASE_NAME>>.firebaseio.com"
        });
        return admin.auth().deleteUser(context.params.uid);
    });

5. Now deploy your Cloud Function with the command firebase deploy --only functions

When a user is deleted in your Firebase Firestore, this code will run and also delete the user from Firebase Auth.

For more information on Firebase Cloud Functions, see https://firebase.google.com/docs/functions/get-started

Answer 3

Just apply this code same way that you have done authentication.

var user = firebase.auth().currentUser;

user.delete().then(function() {
  // User deleted.
}).catch(function(error) {
  // An error happened.
});

Answer 4

Using the Javascript API (not the admin SDK)

Like this answer points out for user sign in, a second app must be created to be able to delete another user than the one logged in.

This is how I did it:

  async deleteUser (user) {
    // Need to create a second app to delete another user in Firebase auth list than the logged in one.
    // https://stackoverflow.com/a/38013551/2012407
    const secondaryApp = firebase.initializeApp(config, 'Secondary')

    if (!user.email || !user.password) {
      return console.warn('Missing email or password to delete the user.')
    }

    await secondaryApp.auth().signInWithEmailAndPassword(user.email, user.password)
      .then(() => {
        const userInFirebaseAuth = secondaryApp.auth().currentUser
        userInFirebaseAuth.delete() // Delete the user in Firebase auth list (has to be logged in).
        secondaryApp.auth().signOut()
        secondaryApp.delete()

        // Then you can delete the user from the users collection if you have one.
      })
  }

Answer 5

Here is the simple solution for Firebase 9+, if you want to delete the current user:

import { getAuth, deleteUser } from "firebase/auth";

const auth = getAuth();
const user = auth.currentUser;

deleteUser(user).then(() => {
  // User deleted.
}).catch((error) => {
  // An error ocurred
  // ...
});

Answer 6

In my opinion, you can delete specific user without Firebase Admin SDK. You must to storage Username, Password of accounts you want to manage. And login with account - you declare a admin account. After that just follow steps: using firebase auth to logout -> using firebase auth to login with account you want to delete -> using firebase auth to delete that account -> using firebase auth to logout -> login again with that "admin account". Hope this solution help you to delete accounts without using Firebase Admin SDK