Skip to main content

WCF Hosted on a Network Share

Whilst working on a proof of concept WCF service I ran into an interesting security “zone” issue which caused me a few headaches for an afternoon.  I was moving some code out of a prototype WinForm application into a WCF service to prove and demonstrate the next phase of the infrastructure.  The functionality in question reference some custom ‘C’ libraries which had already been proven to run when referenced locally within the Windows application.  However moving the same the code and therefore the reference to the ‘C’ libraries into a WCF service resulted in most calls to the library throwing a “Security Exception”.  Stepping through the debugger, the issue was clear enough, calling “unsafe” code requires Full Trust but even though everything was running locally the WCF service was showing as “Internet” zone and triggering the security exception.   This had me confused for quite a while, I wasn’t hosting the WCF service within IIS (see previous post, no admin rights!), so my only option was the WCFHost application.  No searches on Google could find anything related, everything seemed to indicate that in this situation the WCF application should run in the same security zone/context as the calling application - which I had verified was running in Full Trust mode.

My final attempt before calling it a day and going home was to try and register the DLL within the GAC and hope that solved the trust issue.  It was only when clicking on “Add an assembly to the assembly cache” I noticed that only two drive letters were listed.  The solution I was developing was located on the mapped network drive that didn’t appear in the list.  As a quick test I moved the solution onto one of the non mapped drives, recompiled the application and tried again.  This time everything worked – developing on a mapped drive had resulted in WCFHost dropping the security level that the code was running under! Tags:


Popular posts from this blog

Mocking HttpCookieCollection in HttpRequestBase

When unit testing ASP.NET MVC2 projects the issue of injecting HttpContext is quickly encountered.  There seem to be many different ways / recommendations for mocking HttpContextBase to improve the testability of controllers and their actions.  My investigations into that will probably be a separate blog post in the near future but for now I want to cover something that had me stuck for longer than it probably should have.  That is how to mock non abstract/interfaced classes within HttpRequestBase and HttpResponseBase – namely the HttpCookieCollection class.   The code sample below illustrates how it can be used within a mocked instance of HttpRequestBase.  Cookies can be added / modified within the unit test code prior to being passed into the code being tested.   After it’s been called, using a combination of MOQ’s Verify and NUnit’s Assert it is possible to check how many times the collection is accessed (but you have to include the set up calls) and that the relevant cookies have …

Injecting HttpContextBase into an MVC Controller

It is a shame that when the ASP.NET MVC framework was released they did not think to build IoC support into the infrastructure. All the major components of the MVC engine appear to magically inherit instances of HttpContext and it’s related objects – which can cause no end of problems if you are trying to utilise Unit Testing and IoC. Reading around various articles on the subject just to get around this one problem requires the implementation of several different concepts and you are still left with a work around. The code below, along with the other links referenced in this article is my stab at resolving the issue. There’s probably nothing new here, but it does attempt to relate all the information needed to do this for Castle Windsor. The overview is that all controllers will need to inherit from a base controller, which takes an instance of HttpContext into it’s constructor. It then overrides the property HttpContext in the main controller class, supplying it’s own version…

Unit Testing Workflow Code Activities - Part 1

When I first started looking into Windows Workflow one of the first things that I liked about it was how it separated responsibilities. The workflow was responsible for handling the procedural logic with all it's conditional statements, etc. Whilst individual code activities could be written to handle the business logic processing; created in small easily re-usable components. To try and realise my original perception this series of blog posts will cover the unit testing of bespoke code activities; broken down into: Part One: Unit testing a code activity with a (generic) cast return type (this post)Part Two: Unit testing a code activity that assigns it's (multiple) output to "OutArguments" (Not yet written)So to make a start consider the following really basic code activity; it expects an InArgument<string> of "Input" and returns a string containing the processed output; in this case a reverse copy of the value held in "Input".namespace Ex…