IHandleRequestsForRoles.cs

public class IHandleRequestsForRoles : ActionSelectorMethodAttribute
{
    public string Roles { get; set; }

    public override bool IsValidForRequest(ControllerContext controllerContext, MethodInfo methodInfo)
    {
        var roles = Roles.GetRolesForUser();
        var segments = this.Roles.Split(',');
        bool isValidForRequest = false;

        foreach(var segment in segments)
        {
            if(roles.Contains(segment))
            {
                isValidForRequest = true;
                break;
            }
        }

        return isValidForRequest;
    }
}