Setting HTTP content-type for WCF message-CodePudding

I'm using an external SOAP service, the european National Medicines Verification Systems, over which I have no control. My application uses a WCF client automatically generated from the supplied WSDL. The client uses System.ServiceModel.Channels.Message messages.

The SOAP service uses the same message structure, an "I7RequestType", for 2 messages, the G482LoadTermsAndConditions and the G487LoadDataPrivacyPolicies, and does not "understand" any Action header.

This is my request message, with the ignored Action header :

<?xml version="1.0" encoding="UTF-8"?>
<s:Envelope xmlns:s="http://www.w3.org/2003/05/soap-envelope" xmlns:a="http://www.w3.org/2005/08/addressing">
   <s:Header>
      <a:Action s:mustUnderstand="0">ns:G482RequestMessage</a:Action>
   </s:Header>
   <s:Body xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
      <I7RequestType xmlns="urn:wsdltypes.nmvs.eu:v4.0">
         <Header xmlns="urn:types.nmvs.eu:v4.0">
            <Auth>
               <ClientLoginId>xxxxx</ClientLoginId>
               <UserId>xxxxx</UserId>
               <Password>xxxxx</Password>
            </Auth>
            <UserSoftware xmlns:d5p1="urn:types.nmvs.eu:v4.0" d5p1:name="xxxxx" d5p1:supplier="xxxxx" d5p1:version="2.0" />
            <Transaction>
               <ClientTrxId>xxxxxxxxxxxxxxx</ClientTrxId>
               <Language>fra</Language>
            </Transaction>
         </Header>
      </I7RequestType>
   </s:Body>
</s:Envelope>

The Header Action is ignored by the server, which returns a fault if mustUnderstand is set to 1.

Apparently I should be using the HTTP content-type to permit the server to differentiate the two messages. This is the example I have been given:

    Content-Type : application/soap xml;charset=utf-8;method=SUPPORT-I7RequestType;action="urn:G482LoadTermsAndConditions";

My custom MessageInspector can manipulate the message content in BeforeSendRequest(), but I cannot find any way of adding/modifying the encapsulating HTTP message's headers.

Does anybody know any way of modifying the HTTP headers of an outbound System.ServiceModel.Channels.Message ?

Thanks in advance.

CodePudding user response：

After much searching the problem seems to be due to the generated WCF client not respecting the WSDL and the SOAP 1.2 specification.

This answer WCF Service with wsHttpBinding - Manipulating HTTP request headers gave me all that I needed to create a workaround.

This is the hard-coded proof-of-concept code, based very heavily on Dejan Janjušević's reply, that I added in the function BeforeSendRequest() of my CustomMessageInspector (implements IEndpointBehavior and IClientMessageInspector).

        // Making sure we have a HttpRequestMessageProperty
        HttpRequestMessageProperty httpRequestMessageProperty;
        if( request.Properties.ContainsKey( HttpRequestMessageProperty.Name ) )
        {
            httpRequestMessageProperty = request.Properties[HttpRequestMessageProperty.Name] as HttpRequestMessageProperty;
            if( httpRequestMessageProperty == null )
            {
                httpRequestMessageProperty = new HttpRequestMessageProperty();
                request.Properties.Add( HttpRequestMessageProperty.Name, httpRequestMessageProperty );
            }
        }
        else
        {
            httpRequestMessageProperty = new HttpRequestMessageProperty();
            request.Properties.Add( HttpRequestMessageProperty.Name, httpRequestMessageProperty );
        }

        Console.WriteLine("original Request:");
        Console.WriteLine("{0}\r\n", request);
        request.Headers.Clear();

        httpRequestMessageProperty.Headers.Add( "Content-Type", "application/soap xml;charset=utf-8;method=SUPPORT-I7RequestType;action=\"urn:G482LoadTermsAndConditions\"" );