How to setup multitenancy within an mvc 3 application with ravendb

Question

We've an mvc3 application setup with RavenDb in the following way (with some help from NoSql with RavenDb and Asp.net MVC):

The following code is in the Global.asax

private const string RavenSessionKey = "RavenMVC.Session";
private static DocumentStore documentStore;

protected void Application_Start()
{
    //Create a DocumentStore in Application_Start
    //DocumentStore should be created once per 
    //application and stored as a singleton.
    documentStore = new DocumentStore { Url = "http://localhost:8080/" };
    documentStore.Initialise();
    AreaRegistration.RegisterAllAreas();
    RegisterRoutes(RouteTable.Routes);
    //DI using Unity 2.0
    ConfigureUnity();
}

public MvcApplication()
{
    //Create a DocumentSession on BeginRequest  
    //create a document session for every unit of work
    BeginRequest += (sender, args) => 
    {
      HttpContext.Current.Items[RavenSessionKey] = documentStore.OpenSession();
    }

    //Destroy the DocumentSession on EndRequest
    EndRequest += (o, eventArgs) =>
    {
        var disposable = 
                HttpContext.Current.Items[RavenSessionKey] as IDisposable;

        if (disposable != null)
            disposable.Dispose();
    };
}

//Getting the current DocumentSession
public static IDocumentSession CurrentSession
{
  get { return (IDocumentSession)HttpContext.Current.Items[RavenSessionKey]; }
}

We now want to setup the application to support multitenancy. We want to have two documentstores: one for general purpose, the system database and one for the current (logged in) tennant.

Based on our current setup how do we go about achieving this?

Edit: We now configured our application as following:

We added OpenSession(tenantid) to BeginRequest on the same documentStore (thanks to the answer below from Ayende)

var tenant = HttpContext.Current.Request.Headers["Host"].Split('.')[0];
documentStore.DatabaseCommands.EnsureDatabaseExists(tenant);
HttpContext.Current.Items[RavenSessionKey] = 
                 documentStore.OpenSession(tenant);

Because we are using Ninject for DI we added the following bindings to be sure we are using the right session:

kernel.Bind<ISession>().To<Session>().WhenInjectedInto<UserService>();
kernel.Bind<ISession>().To<TenantSession>();

kernel.Bind<IDocumentSession>().ToMethod(ctx =>        
     MvcApplication.CurrentSession).WhenInjectedInto<Session>();

kernel.Bind<IDocumentSession>().ToMethod(ctx =>  
     MvcApplication.CurrentTenantSession).WhenInjectedInto<TenantSession>();

Maybe there is a better way to configure multitenancy with ravendb and mvc?

Answer 1

AndrewF,

You are going to have two sessions, then. One that is the defualt (OpenSession()) and the other that is for the tenant (OpenSession(TenantId))