如何在ASP.NET MVC 3应用程序中实现共享状态？

Question

I'm writing a basic RESTful service, and decided I'd use ASP.NET MVC 3 for the task. My application is going to be responsible for maintaining a persistent connection to a server per user (for now). I had assumed that Application_Start is the place to register static/shared state (like persistent connections), but after reading the documentation for Unity.MVC3, it appears that each request/response cycle will trigger the creation of services (by calling Application_Start).

The documentation I refer to says:

On every request, one UpperCaseService, one LowerCaseService and one ExampleContext are instantiated by DependencyResolver via Unity. At the end of the request, the ExampleContext is automatically disposed

After reading other documentation, and from what I already assumed, Application_Start would be called per AppDomain spawned (again assumed that this would be in the vicinity of how many cores there are on the server).

So, what would be an effective way of maintaining a set of persistent connections to a server, that survive the request/response phase, and if possible, are shared between all AppDomains that the IIS server has created?

It might help to mention that this web service is only going to be consumed by another web site. It is essentially an Authentication Proxy server, however, in the future, it is going to do a lot more. Therefore, I can't just cache the response, as future requests will be required, and reauthenticating is not an option.

Answer 1

If you want to survive AppDomain restarts and share state between multiple ASP.NET applications you will have to go out of the IIS process and store this in a central location that is accessible from all applications. A database is a good candidate.