ASP.NET MVC3 creating new sessions on ajax requests

Question

Well, I finally had to create an account here. Been using this for years and have often found my answer here, but not this time. Well, I actually have found a lot of people with similar problems, but none of their solutions have helped me.

I have started on a new MVC3 project, so it's quite simple so far. I've made a handful before, so I kinda know what I'm doing (but not quite, obviously, why else be here ;-)

My problem is apparently a fairly common one: A request starts a new Session, even though the user already has one.

The most frustrating part of this is, it works perfectly on my hosted service, but is broken on localhost.

I have done a number of things to solve this:

• There is no underscore in my computer's name.
• The Session contains custom data (the error only occurs after user has logged in).
• I have added the following to web.config (hmpf, guess you'll have to assume the gt / lt chars):

    httpProtocol
      customHeaders
        clear /
        add name="Access-Control-Allow-Origin" value="*" /
      /customHeaders
    /httpProtocol

• and this too:

  modules runAllManagedModulesForAllRequests="false"/

• With InProc sessionstate, I have tried with 'cookieless' both true and false.

• My hosts file contains nothing about localhost.

hm. Looking at this list I'm sure I've left some out. Some on purpose too, as they were hopeless (yes, even more than the above), and born from desperation.

As mentioned this is particularly unnerving as it works on my host - could there be some configuration settings I need to tweak on the dev server (VS2010)?

I've been working from the premise that the issue is due to cross-domain security (it thinks I'm coming from another domain).

The fail happens on this request:

url: 'http://localhost:50396/moody/changeBuilding/' + elem.selectedIndex,  

It's part of the options array I use with the jQuery.ajax function.

I change the domain when uploading to the host, but only the part localhost:port, everything else in the application is identical.

I've been banging my head against this for 2 days now, and will miss my exam :-( I'm determined to bury this 6 feet under, though.

I would be very grateful for any and all suggestions!

Answer 1

Have you tried using something like fiddler to make sure that the session cookie is being sent in the AJAX request. It should be sent if the domain is the same but it's work checking.

Edit: This SO post on changing ports is worth reading too.

Edit: Given the new information in Charlino's comments (and the sterling detective work carried out therein) if the problem is only on your local dev machine then the easiest way to work around your localhost/127.0.0.1 issue is by manually changing the browser url from 127.0.0.1:50396 to localhost:50396, logging in again to get the new cookie, then you are good to go.

Answer 2

I change the domain when uploading to the host, but only the part localhost:port, everything else in the application is identical.

Reading the above, I image the session cookie isn't being sent because you're changing domains.

Let's sit back and think about how sessions work. Basically ASP.NET contains a collection of sessions and their data. When each request comes in, ASP.NET must map that request to an existing session OR create a new session for them.

So how does ASP.NET know what session belonged to each incoming request? Or know that it needs to create a new request? The only way to know this is if the request contained some information, a 'key', which told ASP.NET what session to give the request... or in the absence of this 'key', create a new session.

How does the request send this 'key'? Through cookies.

So therefore, if you change the domain, the cookies isn't going to be sent... so therefore, ASP.NET will create a new session for the request.