How to restrict a time period in Firestore's rule

Question

I want to restrict a time period using Firestore.

For example a user can access an app only between 9:00 and 21:00. I don't know how to store the restricted time. At first I though I should use timestamp type. But I want for user to access based on hours. So I mean I need just hours.

Based on this article Storing time only in Firestore, Should I save the time like this?

 - startAccess : 900
 - endAccess: 2100

This data type is Int type.

And if I save those type in Firestore, I don't know how to filter it exactly. I read an official document and we can restrict an access like this.

allow read: if
  request.time > something rule?

But if I use just Int type above, I think I can't filter the access time. How do I achieve it?

Answer 1

I haven't test this yet, But should look like:

allow read: if request.time.hours() >= 9 && request.time.hours() < 21;

Document Interface: Timestamp