How To Send Notification To Multiple Device Token Using Firebase Cloud Functions

I am new in using Firebase Cloud Functions and JavaScript and I was able to send notification to a single device using Firebase Cloud Functions(JavaScript). Now I am trying to send

Solution 1:

First of all, you shouldn't be adding tokens like below, if that's how you've organised your DB. There might be multiple token for a single uid

/receivers
  /event1
       /uid1: device_token1
       /uid2: device_token2
       /uid3: device_token3
       /uid4: device_token4

And for sending notifications to multiple UIDs, I've written a script here

Also, update your question about what exactly the problem you are facing.