title: How to get current timestamp of firebase server in milliseconds?
body: <p>I wanted to get firebase current timestamp, not able to find a way to get that. I want to save child as shown in the image. And for that I've to get timestamp and get the date accordingly. Please help...</p>
  
  <p><img src="https://i.stack.imgur.com/4Kg9j.png" alt="here is the result I want to get"></p>