Google Cloud function to automatically disable new users

block-signup.md

Firebase Authentication

Via this Cloud Function you can automatically disable new users.

To deploy this, replace with yours and deploy via command line with:

gcloud functions deploy block-signup --runtime nodejs10 --trigger-event providers/firebase.auth/eventTypes/user.create --trigger-resource <PROJECT-ID>

index.js

/**
 * @see https://github.com/firebase/firebaseui-web/issues/99
 */

process.env.GCLOUD_PROJECT = '<PROJECT-ID>'

const functions = require('firebase-functions');
const admin = require("firebase-admin");

admin.initializeApp();

exports.blockSignup = functions.auth.user().onCreate(event => {
    console.log("event", event);

    return admin.auth().updateUser(event.uid, { disabled: true })
        .then(userRecord => console.log("Auto blocked user", userRecord.toJSON()))
        .catch(error => console.log("Error auto blocking:", error));
});

package.json

{
  "name": "block-signup",
  "version": "1.0.0",
  "description": "``` cd functions/block-signup gcloud functions deploy block-signup --runtime nodejs10 --trigger-event providers/firebase.auth/eventTypes/user.create --trigger-resource <PROJECT-ID> ```",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "firebase-admin": "^8.9.0",
    "firebase-functions": "^3.3.0"
  }
}