Using ViewModels in asp.net mvc 3 - asp.net-mvc

Question

Here is my scenario: (These all have to accomplished in the same view as an accepted requirement)
User enters a few search criterias to search users.
Page lists the search results with an update link besides.
User clicks on one of the update links and a form appears to enable editing the data.
User does changes and saves the data that binded to form.
I used a view model for this view. Here it is.
[Serializable]
public class UserAddModel
{
public UserSearchCriteria UserSearchCriteria { get; set; }
public UserEntity User { get; set; }
public List<UserPrincipalDto> SearchResults { get; set; }
}
And here is my controller:
using System;
namespace x.Web.BackOffice.Controllers
{
[Export]
[PartCreationPolicy(CreationPolicy.NonShared)]
[Authorize(Roles = "Admin")]
public class UserController : Controller
{
private readonly IAuthentication _authentication;
private readonly List<RoleEntity> roles = new Y.Framework.Data.Repository<RoleEntity>().Get(null).ToList();
private Repository<UserEntity> repository = new Repository<UserEntity>();
[ImportingConstructor]
public UserController(IAuthentication authentication)
{
this._authentication = authentication;
}
public ActionResult Index()
{
return View(new UserAddModel());
}
[HttpPost]
public ActionResult GetSearchResults(UserAddModel model)
{
if (ModelState.IsValid)
{
try
{
List<UserPrincipalDto> results =
_authentication.SearchUsers(
ConfigurationManager.AppSettings["DomainName"],
model.UserSearchCriteria.FirstName,
model.UserSearchCriteria.LastName,
model.UserSearchCriteria.Username);
model.SearchResults = results;
Session["UserAddModel"] = model;
return View("Index", model);
}
catch (Exception ex)
{
Logger.Log(ex, User.Identity.Name);
}
}
else
{
ModelState.AddModelError("", "Error!");
}
Session["UserAddModel"] = model;
return View("Index", model);
}
public ActionResult Save(string username)
{
UserAddModel model = Session["UserAddModel"] as UserAddModel;
UserEntity exists = repository.Get(u => u.Username == username).FirstOrDefault();
if (exists == null)
{
UserPrincipal userPrincipal =
_authentication.GetUserDetails(
ConfigurationManager.AppSettings["DomainName"],
username);
model.User = new UserEntity();
model.User.Id = userPrincipal.Guid.Value;
model.User.FirstName = userPrincipal.DisplayName.FullNameToFirstName();
model.User.LastName = userPrincipal.DisplayName.FullNameToLastName();
model.User.Email = userPrincipal.EmailAddress;
model.User.Username = userPrincipal.SamAccountName;
}
else
{
model.User = new UserEntity();
model.User.Id = exists.Id;
model.User.FirstName = exists.FirstName;
model.User.LastName = exists.LastName;
model.User.Email = exists.Email;
model.User.Username = exists.Username;
model.User.RoleId = exists.RoleId;
}
ViewBag.Roles = roles;
return View("Index", model);
}
[HttpPost]
public ActionResult Save(UserAddModel model)
{
UserEntity exists = repository.Get(u => u.Id == model.User.Id).FirstOrDefault();
if (exists == null)
{
Result result = repository.Save(model.User);
HandleResult(result, model);
}
else
{
Result result = repository.Save(model.User, PageMode.Edit);
HandleResult(result, model);
}
ViewBag.Roles = roles;
return View("Index", model);
}
}
}
As you see there are two different forms in my view and I'm storing the whole view model in Session in my controller. But I think this is not fine enough. What if session expires or what if I have to deploy my application using a load balancer?
What is the best way to develop this kind of page? I'm open to any kind of suggestions.
Thanks in advance,