Question

Hey there, I’ve succesfull been able to use property injection in my FilterAttribute, however I’m wondering whether its possible to move it into the constructor instead?

My current code:

// AuthAttribute.cs

public class AuthAttribute : ActionFilterAttribute
{
    public Roles _authRoles { get; private set; }

    [Inject]
    private readonly IAuthorizationService _service;

    public AuthAttribute(Roles roles)
    {
        _authRoles = roles;
    }

    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        if (!filterContext.HttpContext.User.Identity.IsAuthenticated)
        {
            string redirectOnSuccess = filterContext.HttpContext.Request.Url.AbsolutePath;
            string redirectUrl = string.Format("?returnUrl={0}", redirectOnSuccess);
            string loginUrl = FormsAuthentication.LoginUrl + redirectUrl;

            filterContext.HttpContext.Response.Redirect(loginUrl, true);
        }
        else
        {
            bool isAuthorized = _service.Authorize(GetUserSession.Id, _authRoles.ToString());

            if (!isAuthorized)
            {
                // TODO: Make custom "Not Authorized" error page.
                throw new UnauthorizedAccessException("No access");
            }
        }
    }
}

 

// TestController.cs

[Auth(Roles.Developer)]
public ActionResult Index()
{
    // Some smart logic
}

Thanks in advance!

Answer 1

No, this isn’t possible as the parameters for the constructors must be simple types.

For testing purposes, you could have another constructor (since you shouldn’t be using an IoC container with testing):

public class AuthAttribute : ActionFilterAttribute
{
    public Roles _authRoles { get; private set; }

    [Inject]
    private readonly IAuthorizationService _service;

    public AuthAttribute(Roles roles)
    {
        _authRoles = roles;
    }

    public AuthAttribute(Roles roles, IAuthorizationService authSvc)
        : this(roles)
    {
        this.service = authSvc;
    }

    // ...
}