Firebase function always return a promise but my code works even without returning a promise...

I'm used to Java, when a function says you return something. Then you should return that thing.However, I don't understand how javaScript/Node works. How is the code working and i'm not getting any errors ?Here is the function i'm taking about http://ift.tt/2tWnLfN

Submitted June 23, 2017 at 03:15PM by sohaeb