Polar Built-in Constants

Polar provides built-in “constants”, which can be referenced in rules and then evaluated at runtime.

@current_unix_time

The @current_unix_time keyword can be used to refer to the unix time (the number of seconds that have elapsed since January 1, 1970 at midnight UTC) at the time of a query.

@current_unix_time returns an Integer.

For example, if you have a fact expires_at(File:foo, 1670280790) indicating the time that the “foo” file expires, you could use this for time-based access:

has_permission(_: Actor, "read", file: File) if
  expires_at(file, time) and @current_unix_time < time;