title: How to use Firebase Authentication service and have user in our own database?
body: <p>I have my own <code>node.js</code> server setup so I don't need Firebase storage and real-time database service. From the client side (mainly Android) I am trying to authenticate the user using  Firebase Authentication service(G+ and FB login) but that creates users in firebase database. How can I create users in my database also?</p>
  
  <p>Currently, I am simply sending user id created by Firebase to my server and saving it in DB and generating a <code>JWT</code> to validate subsequent REST API requests to my server.</p>