Question

I have created a module to handle authentication to Microsoft HealthVault. In the BeginRequest event handler I am checking for the authToken and when it’s received, I am creating a new cookie to hold the user’s information for use later on in the controller.

I am losing the cookie but maybe I am looking in the wrong place.

The event handler take an HttpApplication as the only parameter, so I add the cookie to application.Response.Cookies collection. The question comes down to: is this instance of HttpApplication a singleton? Is it the same as System.Web.HttpContext.Current.ApplicationInstance?

Perhaps though, cookies set at this point in the lifecycle are later wiped out. Is that what I am doing wrong?

Any help is greatly appreciated.

UPDATE

I have changed a few things since I posed the question. I am now handling PreRequestEventHandler in my HttpModule. I am letting HealthVault’s WebApplicationUtilities object do the cookie creation and storage, though conceptually nothing has really changed. I am not having any trouble creating the cookie or reading it the first time after it’s created.

Here is my cookie creation code in the HttpModule event handler:

static void PreRequestHandlerExecute(Object sender, EventArgs e)
{
    HttpContext ctx = System.Web.HttpContext.Current;
        string authToken = ctx.Request.Params["wctoken"];
        if (!String.IsNullOrEmpty(authToken))
        {
            personInfo = WebApplicationUtilities.GetPersonInfo(authToken);
            WebApplicationUtilities.SavePersonInfoToCookie(ctx, personInfo);

            NameValueCollection query = HttpUtility.ParseQueryString(ctx.Request.Url.Query);
            query.Remove("wctoken");
            query.Remove("suggestedtokenttl");

            UriBuilder newUrl = new UriBuilder(ctx.Request.Url);
            newUrl.Query = query.ToString();
            //app.Response.Redirect(newUrl.Uri.OriginalString);
        }
}

Notice that the redirect is commented. On the first request (after auth) the cookie is created and my default action is able to then read it using LoadPersonInfoFromCookie(). I found that doing the redirect caused the cookie not to be sent to the client.

I have also noticed that on the subsequent requests, the cookie is not present in the Request.Cookies collection, so when LoadPersonInfoFromCookie() runs, I end up with a null. Strangely I can see the cookie in the Response object, but the contents are empty.

Here is the action code, just because…

public HttpContext Context
{
    get { return System.Web.HttpContext.Current; }
}

public ActionResult Dashboard()
    {
        try
        {
            HealthVaultAccountModel model = new HealthVaultAccountModel();
            PersonInfo personInfo = WebApplicationUtilities.LoadPersonInfoFromCookie(Context);
            if (personInfo != null)
                model.PersonName = personInfo.Name;
            return View(model);
        }
        catch (Exception ex)
        {
            return RedirectToAction("Index", "Error");
        }
    }

UPDATE

Here is the cookie from the Immediate Window. I even bumped the Expires time out 30 days.

In the default action right after it is created

Context.Request.Cookies["_wcpage"]
{System.Web.HttpCookie}
    Domain: null
    Expires: {8/13/2012 5:24:02 PM}
    HasKeys: true
    HttpOnly: true
    Name: "_wcpage"
    Path: "/"
    Secure: true
    Shareable: false
    Value: "p=1:1234-pVTbctowEP0V..."
    Values: {p=1%3a1234-pVTbctowEP0V...}

In the action on the next request

Context.Request.Cookies["_wcpage"]
null

Interestingly the cookie is defined in the response object, but the value is gone and the expires time is reset.

Context.Response.Cookies["_wcpage"]
{System.Web.HttpCookie}
    Domain: null
    Expires: {1/1/0001 12:00:00 AM}
    HasKeys: false
    HttpOnly: false
    Name: "_wcpage"
    Path: "/"
    Secure: false
    Shareable: false
    Value: ""
    Values: {}

Answer 1

How are you creating/fetching the cookie? The SavePersonInfoToCookie and LoadPersonInfoFromCookie methods on the WebApplicationUtilities class will do it for you.

BeginRequest:

// given an authToken from the querystring/post values
var personInfo = WebApplicationUtilities.GetPersonInfo(authToken);
WebApplicationUtilities.SavePersonInfoToCookie(application.Context, personInfo);

Controller:

var personInfo = WebApplicationUtilities.LoadPersonInfoFromCookie(HttpContext);