How would I change a certain field of a document every 3 hours with Firestore?

Question

I’m making an app that requires every 3 hours to update a certain field of a document. How would I do that?

Answer 1

You're looking for something called "Cron Job".

The Idea behind it: You create an HTTP triggered method in Firebase Functions, and assign an outer service (for example: Google App Engine) that is responsible to send the HTTP request routinely.

There isn't any Firebase-built-in solution, but you could use Google App Engine / other Cloud utility available out there.

Here's an Excellent article for implementing one with Firebase Functions.

This one might help as well (Firebase Blog).