Thursday 25 February 2010

Coming soon to MapGuide Open Source 2.2


The problem stuck out like a sore thumb for the past 2 years, but as of the next release of MapGuide Open Source, Windows Server 2003 users can now choose the web site they want to install the MapGuide Web Extensions to!

Why did it take so long? Doing the custom action in .net would've been a piece of cake, but since we cannot afford the luxury of assuming the .net Framework as a mandatory requirement, we had to resort to doing the custom action in C++, which is no walk in the park. Thankfully, wcautil and IMSAdminBase provided the required tools to make this possible! Also, real world priorities had stolen whatever time I had to tackle this problem, until now.

Note that this applies to IIS6 only, as IIS7 uses a totally different form of configuration although we can still apparently use the same IMSAdminBase COM API, so if time/resource permitting I may be able to give IIS7 the same loving treatment.

Wednesday 3 February 2010

Technical Question Etiquette

This post is a bit ranty, but I really need to get this off my chest.

On the same day where I lost over half a workday to some stupid Visual Studio problem, I had lost several more due to problems with another Microsoft product: IIS

The problem was that I had two IIS websites which weren't serving content. I did a check of the ASP.net versions and the host headers just to make sure nothing was misconfigured. I even rebooted said server to see if it would fix the problem to no avail. Event logs did little to help me, so with very few other options, I turned to the Oracle of Google for help.

Google was not kind to my pleas for help. There was only really one relevant result on the topic at hand, when I clicked on the result, the question pretty much was similar to mine. The only problem was, the reply to the question was from the original asker, which simply read:

Don't worry. I got it solved.

End of sentence. End of story.

I think as a general rule of etiquette, if you have a question and you somehow answered it yourself, please do tell us how you solved the problem because there may be others (like myself on that day) that have the same problem and would like to know how you solved it too!

/end rant

WPF + Geospatial Platform API = A recipe for failure

If you use WPF in your AutoCAD Map applications and you are using the Geospatial Platform API you may encounter something like this when designing any WPF content:



The type initializer for '<Module>' threw an exception.
at System.Reflection.CustomAttribute._CreateCaObject(Void* pModule, Void* pCtor, Byte** ppBlob, Byte* pEndBlob, Int32* pcNamedArgs)
at System.Reflection.CustomAttribute.CreateCaObject(Module module, RuntimeMethodHandle ctor, IntPtr& blob, IntPtr blobEnd, Int32& namedArgs)
at System.Reflection.CustomAttribute.GetCustomAttributes(Module decoratedModule, Int32 decoratedMetadataToken, Int32 pcaCount, RuntimeType attributeFilterType, Boolean mustBeInheritable, IList derivedAttributes)
at System.Reflection.CustomAttribute.GetCustomAttributes(Assembly assembly, RuntimeType caType)
at System.Reflection.Assembly.GetCustomAttributes(Boolean inherit)
at MS.Internal.ReferenceAssemblyUtils.SafeGetCustomAttributes(Assembly assembly, Type filter, Boolean inherit)
at MS.Internal.Xaml.ReflectionProjectNode.BuildNamespaces()
at MS.Internal.Xaml.ReflectionProjectNode.Find(Identifier namespaceUri)
at MS.Internal.Xaml.PrefixScope.FindType(XamlName name)
at MS.Internal.Xaml.XmlElement.FindElementType(PrefixScope parentScope, IParseContext context)
at MS.Internal.DocumentTrees.Markup.XamlSourceDocument.get_RootType()
at Microsoft.Windows.Design.Documents.Trees.MarkupDocumentTreeManager.get_RootType()
at Microsoft.Windows.Design.Documents.MarkupDocumentManager.CalculateLoadErrorState()
at Microsoft.Windows.Design.Documents.MarkupDocumentManager.get_LoadState()
at MS.Internal.Host.PersistenceSubsystem.Load()
at MS.Internal.Host.Designer.Load()
at MS.Internal.Designer.VSDesigner.Load()
at MS.Internal.Designer.VSIsolatedDesigner.VSIsolatedView.Load()
at MS.Internal.Designer.VSIsolatedDesigner.VSIsolatedDesignerFactory.Load(IsolatedView view)
at MS.Internal.Host.Isolation.IsolatedDesigner.BootstrapProxy.LoadDesigner(IsolatedDesignerFactory factory, IsolatedView view)
at MS.Internal.Host.Isolation.IsolatedDesigner.BootstrapProxy.LoadDesigner(IsolatedDesignerFactory factory, IsolatedView view)
at MS.Internal.Host.Isolation.IsolatedDesigner.Load()
at MS.Internal.Designer.DesignerPane.LoadDesignerView()


A nested exception occurred after the primary exception that caused the C++ module to fail to load.

at <CrtImplementationDetails>.ThrowNestedModuleLoadException(Exception innerException, Exception nestedException)
at <CrtImplementationDetails>.ThrowNestedModuleLoadException(Exception , Exception )
at <CrtImplementationDetails>.LanguageSupport.Cleanup(LanguageSupport* , Exception innerException)
at <CrtImplementationDetails>.LanguageSupport.Initialize(LanguageSupport* )
at .cctor()


Type constructor threw an exception.
at System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode, IntPtr errorInfo)
at System.Runtime.InteropServices.Marshal.ThrowExceptionForHR(Int32 errorCode)
at <CrtImplementationDetails>.DoCallBackInDefaultDomain(IntPtr function, Void* cookie)
at <CrtImplementationDetails>.DoCallBackInDefaultDomain(IntPtr , Void* )
at <CrtImplementationDetails>.LanguageSupport.InitializeDefaultAppDomain(LanguageSupport* )
at <CrtImplementationDetails>.LanguageSupport._Initialize(LanguageSupport* )
at <CrtImplementationDetails>.LanguageSupport.Initialize(LanguageSupport* )

Though you can still build and run the project, the WPF designer is completely hosed, all intellisense is lost and as a result, the WPF designer becomes a bloated version of notepad.

The reason that happens is because the Autodesk.Map.Platform.dll is actually just a thin managed wrapper to the unmanaged AcMap* dlls in your AutoCAD Map installation, so the WPF designer is actually trying to locate these dlls from either:
  • The project's output directory
  • Or, some special working directory that's defined by Visual Studio (where this is, I have no idea)
After 5 hours of sleuthing around, I have found an acceptable workaround.

Simply put the AutoCAD Map installation directory into your PATH environment variable and restart Visual Studio. The WPF designer will correctly locate the AcMap* dlls and you'll regain full designer functionality.

This little tip will no doubt be useful to someone out there. I lost 5 work hours so you don't have to :-)