Visual Studio 2012 install broke my 2010 WCF project

Question

I've installed VS 2012 and am successfully using it on some web projects, but something with it has caused my web service project to break. I'm still using VS 2010 on the web service project and have not opened it in 2012.

Everything compiles and works correctly except when it tries to create an instance of a class in my referenced weblog project, then it throws this error:

This method or property is not supported after HttpRequest.GetBufferlessInputStream has been invoked.

I can not find anywhere in the project where GetBufferlessInputStream is used explicitly.

If I jump over the weblog code, everything executes correctly.

I can't find anyone else who has received this error to try and narrow it down, any ideas where to start?

Stack

   at System.Web.HttpRequest.get_InputStream()
   at OAS.Web.Log.WebEvent..ctor(EventType type, HttpContext context, String applicationName)
   at OAS.Web.Log.WebTrace..ctor(HttpContext context, String applicationName)
   at OAS.Web.AdvisorServices.Extensions.OperationLoggerParameterInspector.BeforeCall(String operationName, Object[] inputs) in C:\SourceControl\OAS\IM.NET3.0\Web\AdvisorServices\OAS.Web.AdvisorServices.Extensions\OperationLogger\OperationLoggerParameterInspector.cs:line 54

**EDIT - Bonus Question

Why are these Framework 4.5 properties affecting my 4.0 solution?

Answer 1

Note : This issue has been fixed in .net 4.5.1. You can see the fix with 4.5.1. Once you have .net 4.5.1 add the following appSetting to switch back to the old behavior.

<configuration>      
<appSettings>
      <add key="wcf:serviceHostingEnvironment:useClassicReadEntityBodyMode" value="true" />
</appSettings> 
</configuration>

Here is how you can create a HttpModule to force ReadEntityBodyMode to be "classic" : http://blogs.msdn.com/b/praburaj/archive/2012/09/13/accessing-httpcontext-current-request-inputstream-property-in-aspnetcompatibility-mode-throws-exception-this-method-or-property-is-not-supported-after-httprequest-getbufferlessinputstream-has-been-invoked.aspx

To answer your other question (Why are these Framework 4.5 properties are effecting my 4.0 solution?): .net 4.5 is an in-place upgrade of .net 4.0. So even if your project is targeting 4.0, since VS 2012 installs 4.5 runtime, some of the 4.5 behaviors take effect.

EDIT

Blog Entry:

In .net 4.5 WCF leveraged the buffer less input stream for scalability benefits. As a result when you try to access the HttpContext.Current.Request.InputStream property you may end up with the below exception, as the InputStream property tries to get you handle to the Classic stream as they both are incompatible.

“This method or property is not supported after HttpRequest.GetBufferlessInputStream has been invoked.”

If you had a WCF 4.0 app which worked perfectly but on upgrading your .net framework to 4.5 you notice the service failing on accessing this property, here is the way to work-around the issue:

• Add a simple HttpModule in the same WCF project which will access the InputStream property for each request before WCF reads it so that it will enforce the HttpContext.Request.ReadEntityBody to be "Classic" and will ensure compatibility.

  public class WcfReadEntityBodyModeWorkaroundModule : IHttpModule    
  {    
      public void Dispose() { }
  
      public void Init(HttpApplication context) {    
          context.BeginRequest += context_BeginRequest;    
      }    
  
      void context_BeginRequest(object sender, EventArgs e) {
          //This will force the HttpContext.Request.ReadEntityBody to be "Classic" and will ensure compatibility..    
          Stream stream = (sender as HttpApplication).Request.InputStream;    
      }    
   } 
  

• Register this module in your web.config by adding these lines in <configuration> <modules> setting.

  <system.webServer>
      <modules>
          <!-- Register the managed module -->
          <add name="WcfReadEntityBodyModeWorkaroundModule" type="MyAssembly.WcfReadEntityBodyModeWorkaroundModule, MyAssembly" />
      </modules>
  

• If you are using an app pool in classic mode, you will need to add the module to this section in the web.config:

  <system.web>
      <httpModules>
          <add name="WcfReadEntityBodyModeWorkaroundModule" type="MyAssembly.WcfReadEntityBodyModeWorkaroundModule, MyAssembly" />
      </httpModules>
  

If your project cannot be modified, then you can write this Http module in a separate assembly, GAC it separately and register this module in the web.config.

Now try accessing the service it should succeed for you!