I need to do something fairly simple: in my ASP.NET MVC application, I want to set a custom IIdentity / IPrincipal. Whichever is easier / more suitable. I want to extend the default so that I can call something like User.Identity.Id
and User.Identity.Role
. Nothing fancy, just some extra properties.
I've read tons of articles and questions but I feel like I'm making it harder than it actually is. I thought it would be easy. If a user logs on, I want to set a custom IIdentity. So I thought, I will implement Application_PostAuthenticateRequest
in my global.asax. However, that is called on every request, and I don't want to do a call to the database on every request which would request all the data from the database and put in a custom IPrincipal object. That also seems very unnecessary, slow, and in the wrong place (doing database calls there) but I could be wrong. Or where else would that data come from?
So I thought, whenever a user logs in, I can add some necessary variables in my session, which I add to the custom IIdentity in the Application_PostAuthenticateRequest
event handler. However, my Context.Session
is null
there, so that is also not the way to go.
I've been working on this for a day now and I feel I'm missing something. This shouldn't be too hard to do, right? I'm also a bit confused by all the (semi)related stuff that comes with this. MembershipProvider
, MembershipUser
, RoleProvider
, ProfileProvider
, IPrincipal
, IIdentity
, FormsAuthentication
.... Am I the only one who finds all this very confusing?
If someone could tell me a simple, elegant, and efficient solution to store some extra data on a IIdentity without all the extra fuzz.. that would be great! I know there are similar questions on SO but if the answer I need is in there, I must've overlooked.
Here's how I do it.
I decided to use IPrincipal instead of IIdentity because it means I don't have to implement both IIdentity and IPrincipal.
Create the interface
interface ICustomPrincipal : IPrincipal
{
int Id { get; set; }
string FirstName { get; set; }
string LastName { get; set; }
}
CustomPrincipal
public class CustomPrincipal : ICustomPrincipal
{
public IIdentity Identity { get; private set; }
public bool IsInRole(string role) { return false; }
public CustomPrincipal(string email)
{
this.Identity = new GenericIdentity(email);
}
public int Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
}
CustomPrincipalSerializeModel - for serializing custom information into userdata field in FormsAuthenticationTicket object.
public class CustomPrincipalSerializeModel
{
public int Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
}
LogIn method - setting up a cookie with custom information
if (Membership.ValidateUser(viewModel.Email, viewModel.Password))
{
var user = userRepository.Users.Where(u => u.Email == viewModel.Email).First();
CustomPrincipalSerializeModel serializeModel = new CustomPrincipalSerializeModel();
serializeModel.Id = user.Id;
serializeModel.FirstName = user.FirstName;
serializeModel.LastName = user.LastName;
JavaScriptSerializer serializer = new JavaScriptSerializer();
string userData = serializer.Serialize(serializeModel);
FormsAuthenticationTicket authTicket = new FormsAuthenticationTicket(
1,
viewModel.Email,
DateTime.Now,
DateTime.Now.AddMinutes(15),
false,
userData);
string encTicket = FormsAuthentication.Encrypt(authTicket);
HttpCookie faCookie = new HttpCookie(FormsAuthentication.FormsCookieName, encTicket);
Response.Cookies.Add(faCookie);
return RedirectToAction("Index", "Home");
}
Global.asax.cs - Reading cookie and replacing HttpContext.User object, this is done by overriding PostAuthenticateRequest
protected void Application_PostAuthenticateRequest(Object sender, EventArgs e)
{
HttpCookie authCookie = Request.Cookies[FormsAuthentication.FormsCookieName];
if (authCookie != null)
{
FormsAuthenticationTicket authTicket = FormsAuthentication.Decrypt(authCookie.Value);
JavaScriptSerializer serializer = new JavaScriptSerializer();
CustomPrincipalSerializeModel serializeModel = serializer.Deserialize<CustomPrincipalSerializeModel>(authTicket.UserData);
CustomPrincipal newUser = new CustomPrincipal(authTicket.Name);
newUser.Id = serializeModel.Id;
newUser.FirstName = serializeModel.FirstName;
newUser.LastName = serializeModel.LastName;
HttpContext.Current.User = newUser;
}
}
Access in Razor views
@((User as CustomPrincipal).Id)
@((User as CustomPrincipal).FirstName)
@((User as CustomPrincipal).LastName)
and in code:
(User as CustomPrincipal).Id
(User as CustomPrincipal).FirstName
(User as CustomPrincipal).LastName
I think the code is self-explanatory. If it isn't, let me know.
Additionally to make the access even easier you can create a base controller and override the returned User object (HttpContext.User):
public class BaseController : Controller
{
protected virtual new CustomPrincipal User
{
get { return HttpContext.User as CustomPrincipal; }
}
}
and then, for each controller:
public class AccountController : BaseController
{
// ...
}
which will allow you to access custom fields in code like this:
User.Id
User.FirstName
User.LastName
But this will not work inside views. For that you would need to create a custom WebViewPage implementation:
public abstract class BaseViewPage : WebViewPage
{
public virtual new CustomPrincipal User
{
get { return base.User as CustomPrincipal; }
}
}
public abstract class BaseViewPage<TModel> : WebViewPage<TModel>
{
public virtual new CustomPrincipal User
{
get { return base.User as CustomPrincipal; }
}
}
Make it a default page type in Views/web.config:
<pages pageBaseType="Your.Namespace.BaseViewPage">
<namespaces>
<add namespace="System.Web.Mvc" />
<add namespace="System.Web.Mvc.Ajax" />
<add namespace="System.Web.Mvc.Html" />
<add namespace="System.Web.Routing" />
</namespaces>
</pages>
and in views, you can access it like this:
@User.FirstName
@User.LastName