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delphisoapattributeswsdl

"attributeGroup" references ignored by Delphi WSDL Import Tool

I am completely new to web services, but not new to Delphi.

I am importing a WSDL file into Delphi 2010 with the "WSDL Importer" wizard. The WSDL file contains some "attributeGroup" tags which Delphi completely ignores, which is presumably a bug, although I haven't yet found an entry on Quality Central for this issue, only mentions in forums like here and here.

My question has several parts:

  1. What is the best workaround?
  2. I have written a Python script to format the WSDL file such that all references to attributeGroup tags are replaced with the declaration of the attributes defined in the attributeGroups; in other words, flattening the references. The output is successfully imported into Delphi via the "WSDL importer" wizard, and looks correct, but I have yet to test whether the messages constructed via this new WSDL file will work correctly. Is this strategy likely to be viable, or should I quit now and move onto something else more productive?

Update

Based on my experiences, and the answers in this question, I decided to go the wrapper route with a C# console application that eats JSON input data and outputs JSON reply data. A Delphi app drives the C# app. The SOAP part of the whole thing is now effortless, and "just works" in C#.NET, and the rest of the functionality is handled well by Delphi. I would recommend this route to anyone else with similar problems. I did try exporting a C# SOAP assembly as a COM library, and connecting to that from Delphi, but it became very complex, because the SOAP specification in my particular app is large and somewhat complex.

Solution

  • Ok, this one took a while.

    According to this post, there are certain tags that the .NET wsdl.exe tool just won't recognize when importing a wsdl file. According to MSDN:

    attributeGroup: Ignored. DataContractSerializer does not support use of xs:group, xs:attributeGroup, and xs:attribute. These declarations are ignored as children of xs:schema, but cannot be referenced from within complexType or other supported constructs.

    This behaviour is also described (albeit in a very hard-to-understand manner) on one of the MSDN blogs. In my specific case, the particular part of the wsdl file causing the problem looks like this:

     <xs:complexType name="PhonesType">
     <xs:annotation>
         <xs:documentation xml:lang="en">Provides detailed phone information.</   xs:documentation>
     </xs:annotation>
     <xs:sequence>
         <xs:element maxOccurs="unbounded" name="Phone">
             <xs:annotation>
                 <xs:documentation xml:lang="en">Used to pass detailed phone information.</xs:documentation>
             </xs:annotation>
             <xs:complexType>
                 <xs:attributeGroup ref="TelephoneInfoGroup"/>
                 <xs:attributeGroup ref="ID_OptionalGroup">
                     <xs:annotation>
                         <xs:documentation xml:lang="en">The ID attribute in this group is a unique identifying value assigned by the creating system and may be used to reference a primary-key value within a database or in a particular implementation.</xs:documentation>
                     </xs:annotation>
                 </xs:attributeGroup>
             </xs:complexType>
         </xs:element>
     </xs:sequence>
 </xs:complexType>

    It seems that the <xs:attributeGroup ref="TelephoneInfoGroup"/> is being ignored by the .NET wsdl.exe tool, just like it was being ignored by the Delphi wsdl importer. In such a situation, where importing fails in both Delphi and .NET, the wsdl file probably has to be changed, and that means I will have to use my home-made python ref-flattener after all.