Throwing SoapException in .Net web service

Question

EDIT: I have scoured high and low for an answer to this and nobody seems to be getting a similar issue. It seems to me that throwing the SoapException should format the response as required, not with just the exception message. Any help gratefully received.

I am trying to return a SoapException that should look something like this (example):

HTTP/1.1 500 Internal Server Error.
Date: Wed, 26 May 2004 05:12:08 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
X-AspNet-Version: 1.1.4322
Cache-Control: private
Content-Type: text/xml; charset=utf-8
Content-Length: 488 

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
 <soap:Body>

   <soap:Fault>
     <faultcode>soap:Server</faultcode>
     <faultstring>BlahBlahBlahBlahBlah</faultstring>
     <detail />
   </soap:Fault>

 </soap:Body>
</soap:Envelope> 

For this I have implemented code like this, taken from the MSDN site for SoapException:

Imports System
Imports System.Web.Services
Imports System.Web.Services.Protocols
Imports System.ComponentModel
Imports System.Xml.Serialization
Imports System.Xml

<System.Web.Services.WebService(Namespace:="http://tempuri.org/")> _
<System.Web.Services.WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
<ToolboxItem(False)> _
Public Class Service1
    Inherits System.Web.Services.WebService

    <WebMethod()>
    Public Sub Process()
        ' Build the detail element of the SOAP fault.
        Dim doc As New System.Xml.XmlDocument()
        Dim node As System.Xml.XmlNode = doc.CreateNode(XmlNodeType.Element, _
            SoapException.DetailElementName.Name, _
            SoapException.DetailElementName.Namespace)

        ' Build specific details for the SoapException.
        ' Add first child of detail XML element.
        Dim details As System.Xml.XmlNode = doc.CreateNode(XmlNodeType.Element, _
            "mySpecialInfo1", "http://tempuri.org/")

        ' Add second child of detail XML element with an attribute.
        Dim details2 As System.Xml.XmlNode = doc.CreateNode(XmlNodeType.Element, _
            "mySpecialInfo2", "http://tempuri.org/")
        Dim attr As XmlAttribute = doc.CreateAttribute("t", "attrName", _
            "http://tempuri.org/")
        attr.Value = "attrValue"
        details2.Attributes.Append(attr)

        ' Append the two child elements to the detail node.
        node.AppendChild(details)
        node.AppendChild(details2)

        'Throw the exception    
        Dim se As New SoapException("Fault occurred", SoapException.ClientFaultCode, _
                                    Context.Request.Url.AbsoluteUri, node)
        Throw se
        Return
    End Sub
End Class

However when I run this, the actual response sent is:

HTTP/1.1 500 Internal Server Error
Server: ASP.NET Development Server/10.0.0.0
Date: Wed, 03 Jul 2013 13:06:26 GMT
X-AspNet-Version: 2.0.50727
Cache-Control: private
Content-Type: text/plain; charset=utf-8
Content-Length: 233
Connection: Close

System.Web.Services.Protocols.SoapException: Fault occurred
   at MyService.Service1.Process() in C:\MyLocation\MyService\Service1.asmx.vb:line 42

How do I get the response formatted like:

<soap:Envelope>
    <soap:Body>
        <soap:Fault>
            <faultcode/>
            <faultstring/>
            <detail/>
        </soap:Fault>
    </soap:Body>
</soap:Envelope>

Answer 1

Your code should work and give you a formatted fault as per the MSDN example or, if you want a result as in the response sample you posted, then a service like this should do the trick:

Imports System
Imports System.Web.Services
Imports System.Web.Services.Protocols
Imports System.ComponentModel
Imports System.Xml.Serialization
Imports System.Xml

<WebService(Namespace:="http://tempuri.org/")> _
<WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
<ToolboxItem(False)> _
Public Class Service1
    Inherits WebService

    <WebMethod()>
    Public Sub Process()
        Dim detailsNode As XmlNode = Nothing
        Dim actorString As String = Nothing
        Throw New SoapException("BlahBlahBlahBlahBlah", SoapException.ServerFaultCode, actorString, detailsNode)
    End Sub
End Class

A call like this:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:tem="http://tempuri.org/">
   <soapenv:Header/>
   <soapenv:Body>
      <tem:Process/>
   </soapenv:Body>
</soapenv:Envelope>

should return this:

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
   <soap:Body>
      <soap:Fault>
         <faultcode>soap:Server</faultcode>
         <faultstring>BlahBlahBlahBlahBlah</faultstring>
         <detail/>
      </soap:Fault>
   </soap:Body>
</soap:Envelope>

You also need to add this to your Web.config file to remove any stacktrace in your fault string:

<configuration>
    <system.web>
        <customErrors mode="On" />
        ...
    ...     
...

Also, it's usually not necessary to build the SoapException by hand but throw more appropriate exceptions and let ASP.NET wrap it in a SoapFault. See here for more details: Using SOAP faults.

Use SoapUI to call your method and you should get the above result. Make sure you make a POST on the SOAP endpoint e.g. http://localhost:8080/Service1.asmx and not on the URL of the test page when you click "Invoke" e.g. http://localhost:8080/Service1.asmx/Process as that does not return SOAP formatted responses.