TheEdge TheEdge - 3 months ago 178
C# Question

Remove Action Node mustUnderstand from WCF soap request using IClientMessageInspector

I am hitting a WCF service using a WSDL I don't have access to and cannot modify. For one of the requests the remote service is dying because we are sending the:

<Action s:mustUnderstand="1"....>


Having searched extensively I cannot find a simple solution to my problem. So,
in a typical message:

<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
<s:Header>
<Action s:mustUnderstand="1" xmlns="http://schemas.microsoft.com/ws/2005/05/addressing/none" />
</s:Header>
<s:Body xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<retrieveBooking xmlns="http://services.rccl.com/Interfaces/RetrieveBooking">
<OTA_ReadRQ TransactionActionCode="RetrievePrice" SequenceNmbr="1" Version="1" xmlns="http://www.opentravel.org/OTA/2003/05/alpha">


I figured I could remove this node as part of message inspector:

internal class MyMessageInspector : IClientMessageInspector
{
public object BeforeSendRequest(ref Message aRequest, IClientChannel aChannel)
{
//Get rid of mustUnderstand Action node
foreach (MessageHeaderInfo headerInfo in aRequest.Headers.UnderstoodHeaders)
{
aRequest.Headers.UnderstoodHeaders.Remove(headerInfo);
}

return null;
}
}


however even though the aRequest.Headers.UnderstoodHeaders is empty after I remove all the elements, I am still seeing the Action node being emitted in the XML.


  1. What do I have to do to make this work?

  2. How do I get at the
    message contents so that I can inspect the name of the first node of
    the body tag retrieveBooking in this case? (I only need to do
    this for a specific message, not all of them)


Answer

And the answer ends up being very simple in the end.

public object BeforeSendRequest(ref Message aRequest, IClientChannel aChannel)
{
   //For the CabinDetail message the API provider has requested that we REMOVE the XML action node from the header as it causes their end to fail
   //<s:Header>
   //<Action s:mustUnderstand="1" xmlns="http://schemas.microsoft.com/ws/2005/05/addressing/none" />
   //</s:Header>
   if (aRequest.ToString().Contains("CabinDetail"))
   {
       int headerIndexOfAction = aRequest.Headers.FindHeader("Action", "http://schemas.microsoft.com/ws/2005/05/addressing/none");
       aRequest.Headers.RemoveAt(headerIndexOfAction);
   }

   return null;
}