SoapExtension for service  
Author Message
Tom Damon





PostPosted: ASMX Web Services and XML Serialization, SoapExtension for service Top

I am trying to write a soap extension to audit incoming requests on an ASP.Net(2.0) service. The service is also a web service client to a downstream server. When configured through WEB.CONFIG, the extension picks up client requests (outgoing to downstream server) just fine, but it does not pick up incoming requests to the service at all. I have tried configuring the extension using the web.config file and an attribute both together and separately, neither seems to work for the incoming service calls. I have been at this a few days now with no progress. Any idea why this is not working Here is the extension code so far, and the configurations I have tried:

using System;

using System.Web.Services;

using System.Web.Services.Protocols;

using System.IO;

using System.Net;

namespace FSPAdminSvc.Audit

{

public class FSPAudit : SoapExtension

{

Stream oldStream;

Stream newStream;

string filename;

// Save the Stream representing the SOAP request or SOAP response into

// a local memory buffer.

public override Stream ChainStream(Stream stream)

{

oldStream = stream;

newStream = new MemoryStream();

return newStream;

}

// When the SOAP extension is accessed for the first time, the XML Web

// service method it is applied to is accessed to store the file

// name passed in, using the corresponding SoapExtensionAttribute.

public override object GetInitializer(LogicalMethodInfo methodInfo, SoapExtensionAttribute attribute)

{

return ((FSPAuditAttribute)attribute).Filename;

}

// The SOAP extension was configured to run using a configuration file

// instead of an attribute applied to a specific XML Web service

// method.

public override object GetInitializer(Type WebServiceType)

{

// Return a file name to log the trace information to, based on the

// type.

return "C:\\" + WebServiceType.FullName + ".log";

}

// Receive the file name stored by GetInitializer and store it in a

// member variable for this specific instance.

public override void Initialize(object initializer)

{

filename = (string)initializer;

}

// If the SoapMessageStage is such that the SoapRequest or

// SoapResponse is still in the SOAP format to be sent or received,

// save it out to a file.

public override void ProcessMessage(SoapMessage message)

{

//if( message.GetType() == typeof(System.Web.Services.Protocols.SoapClientMessage ))

// return;

switch (message.Stage)

{

case SoapMessageStage.BeforeSerialize:

break;

case SoapMessageStage.AfterSerialize:

WriteOutput(message);

break;

case SoapMessageStage.BeforeDeserialize:

WriteInput(message);

break;

case SoapMessageStage.AfterDeserialize:

break;

default:

throw new Exception("invalid stage");

}

}

public void WriteOutput(SoapMessage message)

{

newStream.Position = 0;

FileStream fs = new FileStream(filename, FileMode.Append,

FileAccess.Write);

StreamWriter w = new StreamWriter(fs);

string soapString = (message is SoapServerMessage) "SoapResponse" : "SoapRequest";

w.WriteLine("-----" + soapString + " at " + DateTime.Now);

w.Flush();

Copy(newStream, fs);

w.Close();

newStream.Position = 0;

Copy(newStream, oldStream);

}

public void WriteInput(SoapMessage message)

{

Copy(oldStream, newStream);

FileStream fs = new FileStream(filename, FileMode.Append,

FileAccess.Write);

StreamWriter w = new StreamWriter(fs);

string soapString = (message is SoapServerMessage)

"SoapRequest" : "SoapResponse";

w.WriteLine("-----" + soapString +

" at " + DateTime.Now);

w.Flush();

newStream.Position = 0;

Copy(newStream, fs);

w.Close();

newStream.Position = 0;

}

void Copy(Stream from, Stream to)

{

TextReader reader = new StreamReader(from);

TextWriter writer = new StreamWriter(to);

writer.WriteLine(reader.ReadToEnd());

writer.Flush();

}

}

// Create a SoapExtensionAttribute for the SOAP Extension that can be

// applied to an XML Web service method.

[AttributeUsage(AttributeTargets.Method)]

public class FSPAuditAttribute : SoapExtensionAttribute

{

private string filename = "c:\\log.txt";

private int priority;

public override Type ExtensionType

{

get { return typeof(FSPAudit); }

}

public override int Priority

{

get { return priority; }

set { priority = value; }

}

public string Filename

{

get

{

return filename;

}

set

{

filename = value;

}

}

}

}

in SERVICE CODE:

<FSPAdminSvc.Audit.FSPAudit(Filename:="C:\Projects\Logs\soaptrace.log", Priority:=0)> _

in WEB.CONFIG:

<soapExtensionTypes>

<add type="FSPAdminSvc.Audit.FSPAudit,audit"

priority="1" group="Low"/>

</soapExtensionTypes>



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