Logging raw and compressed HTTP responses in ASP.NET & IIS7 - asp.net

Question

Along the lines of this question I want to create a HttpModule that will do some custom logging of requests and responses for us. Using the code in the most popular answer for that question I've got a HttpModule up and running which does indeed work:
class PortalTrafficModule : IHttpModule
{
public void Dispose()
{
// Do Nothing
}
public void Init(HttpApplication context)
{
context.BeginRequest += new EventHandler(context_BeginRequest);
context.EndRequest += new EventHandler(context_EndRequest);
}
private void context_BeginRequest(object sender, EventArgs e)
{
HttpContext context = ((HttpApplication)sender).Context;
// Create and attach the OutputFilterStream to the Response and store it for later retrieval.
OutputFilterStream filter = new OutputFilterStream(context.Response.Filter);
context.Response.Filter = filter;
context.Items.Add("OutputFilter", filter);
// TODO: If required the request headers and content could be recorded here
}
private void context_EndRequest(object sender, EventArgs e)
{
HttpContext context = ((HttpApplication)sender).Context;
OutputFilterStream filter = context.Items["OutputFilter"] as OutputFilterStream;
if (filter != null)
{
// TODO: Log here - for now just debug.
Debug.WriteLine("{0},{1},{2}",
context.Response.Status,
context.Request.Path,
filter.ReadStream().Length);
}
}
}
(note that the OutputFilterStream class referred to in the code is in the referenced question).
However, the responses seem to be missing some HTTP headers that I see in Fiddler (like "Date") and more importantly, when I turn on compression the responses I'm logging aren't compressed whereas what I see in Fiddler is.
So my question - is it possible to log the compressed content or is this happening in a subsequent step my module can't hook in to?
For the record, I've also tried handling the PreSendRequestContent event and the response is still uncompressed.

Answer 1

Hi although I cannot answer your questions directly I have had cause to do similar things in the past and have found the following resource extremely helpful and enlightening. In the end I managed to acheive what I needed for raw soap headers by configuring the System.Diagnostics node within web config and create a trace log of traffic. I understand that your needs may be more granular than that however I believe this resource may still help.
http://msdn.microsoft.com/en-us/library/ms731859
Of particular interest may be the message log configuration and viewing message logs links from the one above.