Firebase Function to create user after phone validated

onUserCreated.js

import * as admin from 'firebase-admin';

const db = admin.firestore()

export async function onUserCreated(user: any): Promise<boolean> {
	if(typeof user.phoneNumber != "undefined") {
		const batch = db.batch()
		batch.set(db.collection("users").doc(user.uid), { 
			"phoneNumber": user.phoneNumber,
			"creationTime": new Date(user.metadata.creationTime),
		})

		batch.commit()
        return true
	}
    return false
}