how-to-firebase-8-on-create.js

functions.auth.user().onCreate(event => {
  const functions = require('firebase-functions');
  const admin = require('firebase-admin');
  const config = functions.config();

  admin.initializeApp(config.firebase);

  const user = event.data;
  const userRef = admin.database().ref('/users').child(user.uid);

  return userRef.update(user);
});