An authorization extension for ash resources.

To add this extension to a resource, add it to the list of authorizers like so:

use Ash.Resource,
  ...,
  authorizers: [
    Ash.Policy.Authorizer
  ]

A resource can be given a set of policies, which are enforced on each call to a resource action.

For reads, policies can be configured to filter out data that the actor shouldn't see, as opposed to resulting in a forbidden error.

See the policies guide for practical examples.

Policies are solved/managed via a boolean satisfiability solver. To read more about boolean satisfiability, see this page: https://en.wikipedia.org/wiki/Boolean_satisfiability_problem. At the end of the day, however, it is not necessary to understand exactly how Ash takes your authorization requirements and determines if a request is allowed. The important thing to understand is that Ash may or may not run any/all of your authorization rules as they may be deemed unnecessary. As such, authorization checks should have no side effects. Ideally, the checks built-in to ash should cover the bulk of your needs.