How do I configure autofac with WCF under Azure with a WebRole

Question

I am trying to configure a simple project for Azure to use a WCF service with Http bindings, and using Autofac's WCF integration. Currently I am testing locally and hosting under IIS (Azure).

First I set up the project to run without Autofac and can instantiate the service and see the WSDL endpoint exposed through a browser.

I then modified the services svc file and added a Factory definition.

<%@ ServiceHost Language="C#" Debug="true" Service="EposDataService" Factory="Autofac.Integration.Wcf.AutofacServiceHostFactory, Autofac.Integration.Wcf" %>

I next modified the WebRole class:

 public override void Run()
    {
        // This is a sample worker implementation. Replace with your logic.
        Trace.WriteLine("Worker entry point called", "Information");

        var builder = new ContainerBuilder();
        builder.RegisterModule(new ServiceModule());

        //using (m_Container = builder.Build())
        m_Container = builder.Build();
        //{
            AutofacHostFactory.Container = m_Container;
            while (true)
            {
                // sleep 30 minutes. we don't really need to do anything here.
                Thread.Sleep(1800000);
                Trace.WriteLine("Working", "Information");
            }
        //}    
    }

However when I deploy the service locally and try and access the service, I get an error:

The AutofacServiceHost.Container static property must be set before services can be instantiated.

Exception Details: System.InvalidOperationException: The AutofacServiceHost.Container static property must be set before services can be instantiated.

What I don't understand is that the static property is being set in the WebRole but it appears as if something is resetting the assignment. Any suggestions?

The only thing that makes sense is that the AutofacServiceHost type is being initialised in one AppDomain, but the services are running in another. — kiwisurfer, Mar 09 '13 at 21:59
This link seems to imply that this is the case. http://blogs.msdn.com/b/windowsazure/archive/2010/12/02/new-full-iis-capabilities-differences-from-hosted-web-core.aspx — kiwisurfer, Mar 09 '13 at 22:00

score 1 · Answer 1 · edited May 23 '17 at 11:44

The answer appears to be a combination of factors.

First, I moved the Autofac registration and boostrapping from WebRole to Global.asax. This is what helped address the error message I first received.

Secondly I corrected a mistake in my service registration and I reconfigured the registration from:

builder.RegisterType<EposDataService>().As<IEposDataService>()

to

builder.RegisterType<EposDataService>().AsSelf();

Reference: - autofac wcf registration error

Thirdly I qualified the service name in the svc fully. References:

How do I configure autofac with WCF under Azure with a WebRole

1 Answers1