Custom authorization policies and handlers?

Define complex authorization rules using IAuthorizationHandler:

public class MinimumAgeRequirement : IAuthorizationRequirement {

public int Age { get; }

public MinimumAgeRequirement(int age) => Age = age;

public class MinimumAgeHandler :

AuthorizationHandler<MinimumAgeRequirement> {

protected override Task HandleRequirementAsync(...) {

// logic

Register in DI and use with [Authorize(Policy = "...")].