How to bulk delete Firebase anonymous users

Question

Due to my probable misuse of anonymous authentication (see How to prevent Firebase anonymous user token from expiring) I have a lot of anonymous users in my app that I don\'

Answer 1

There is no way in the Firebase Console to bulk-delete users.

There is no API to bulk-delete users.

But there is administrative API that allows you to delete user accounts. See https://firebase.google.com/docs/auth/admin/manage-users#delete_a_user

Answer 2

This code sample uses the Firebase Admin SDK for Node.js, and will delete any user that has no providerData, which means the user is anonymous:

function deleteAnonymousUsers(nextPageToken) {
 adminApp
    .auth()
    .listUsers(20, nextPageToken)
    .then(function(listUsersResult) {
      listUsersResult.users.forEach(function(userRecord) {
        if (userRecord.providerData.length === 0) { //this user is anonymous
         console.log(userRecord); // do your delete here
         adminApp.auth().deleteUser(userRecord.uid)
            .then(function() {
                console.log("Successfully deleted user");
            })
            .catch(function(error) {
                console.log("Error deleting user:", error);
            });
        }
      });
      if (listUsersResult.pageToken) {
        // List next batch of users.
        deleteAnonymousUsers(listUsersResult.pageToken);
      }
    })
    .catch(function(error) {
      console.log('Error listing users:', error);
    });
}

Answer 3

The Firebase Admin SDK can also delete multiple users at once.

Here is Node.js sample.

admin.auth().deleteUsers([uid1, uid2, uid3])
  .then(deleteUsersResult => {
    console.log('Successfully deleted ' + deleteUsersResult.successCount + ' users');
    console.log('Failed to delete ' +  deleteUsersResult.failureCount + ' users');
    deleteUsersResult.errors.forEach(err => {
      console.log(err.error.toJSON());
    });
  })
  .catch(error => {
    console.log('Error deleting users:', error);
  });

Notice: there is a limitation as list all users. The maximum number of users allowed to be deleted is 1000 per batch.

Answer 4

I had the same problem. because Firebase doesn't provide any API to delete bulk users but this is how I have deleted all anonymous users.

Download all the users as json via firebase tool
firebase auth:export users --format=json
https://firebase.google.com/docs/cli/auth#file_format

You can write a firebase cloud function to trigger or write a action method to trigger

import the json file in to your file,

const Users = require('./users.json'); // ES5 <br>
import Users from './users.json'); // ES6 <br>

normally anonymous user doesn't have email so it is easy to delete the record which doesn't have email id

Users.users.map(user => {
    setTimeout(() => {
      admin.auth().deleteUser(user.localId).then(() =>{
        console.log("Successfully deleted user");
      })
      .catch((error) => {
        console.log("Error deleting user:", error);
      });
    }, 20000);
  });

Don't try to reduce the timeout second if you did you may face error.

Error deleting user: { Error: www.googleapis.com network timeout. Please try again.

Answer 5

I faced the same problem today then I found Firebase Admin SDK. I am using Node.js which is very easy to install, so you can try the following code. It is not a complete answer I know but one can build its own script/application to delete stored uids. Yet, there is no way to retrieve a list, so you have to build one somehow every time you create an anonymous account.

First, download your 'serviceAccountKey.json' which can be done through the Firebase Console (Project Settings). In my case I renamed the download file to a more friendly name and saved to documents folder.

console.firebase.google.com/project/yourprojectname/settings/serviceaccounts/adminsdk

Useful links:

• Firebase Admin SDK Setup
• Firebase Admin User Management
• Firebase Admin Database API

Then, play around using Windows cmd.exe or any other shell. The 'npm install -g' installs firebase-admin globally in your machine.

$ npm install firebase-admin -g
$ node
> var admin = require("firebase-admin");
> admin.initializeApp({
  credential: admin.credential.cert("./documents/yourprojectname-firebase-admin.json"),
  databaseURL: "https://yourprojectname.firebaseio.com"
});
> var db = admin.database();
// Of course use an existent UID of your choice
> admin.auth().getUser('2w8XEVe7qZaFn2ywc5MnlPdHN90s').then((user) => console.log
(user))
> admin.auth().deleteUser('2w8XEVe7qZaFn2ywc5MnlPdHN90s').then(function() {
    console.log("Successfully deleted user");
  }).catch(function(error) {
    console.log("Error deleting user:", error);
  });

// To get access to some key/values in your Database:
> var ref = db.ref("users/1234");
> ref.once("value", function(snapshot) {
  console.log(snapshot.val());
});

Answer 6

I just wanted to add a method I just used to (sort-of) bulk-delete. Mostly because I felt clever after doing it and I am not that clever.

I downloaded a mouse-automation application that lets you record your mouse clicks then replay it automatically. I just deleted almost 1000 users while playing the piano lol.

I used Macro Recorder and it worked like a charm. Just recorded a few iterations in the console of me deleting users, set it to repeat 500 times and walked away.

I know this isn't a very technical answer, but it saved me hours of monotonous mouse clicking so hopefully someone else looking for a way to bulk-delete will benefit from it as well. I hated the fact that there was no bulk-delete and really needed a way out of it. It only took about 20 manual deletes to realize there were apps that could do what I was doing.