Separate traffic from multi-threaded program

[Dirty]

I'm using fiddlercore to do some website traffic tests.  Basically, the tests go to a website and verify some http requests were made.  I have a number of different tests that do this across many different websites.  I'm using a test framework that supports parallelism (Nunit 3.0), so I want to be able to run my tests in parallel, but still keep the traffic from each thread separate.  I'm not sure how to do this with fiddlercore, as I can't just give it a process to watch because all of the threads are from the same process.

[Eric Lawrence]

A web proxy like FiddlerCore doesn't have any means of knowing which thread in a given process was responsible for a HTTP(S) request (assuming that the process is even using a single thread per request to being with). The only way to accomplish what you describe would be to have your test pass the desired information to the proxy, for instance via a custom request header (X-THREAD-ID: 123) that FiddlerCore could delete before forwarding the request to the target.

Regards,
Eric Lawrence
Telerik

[Dirty]

Thanks Eric, that was extremely helpful.  For anyone that is wondering, I used Selenium's AddCookie method to throw some info into the header and then pulled it out in the "BeforeRequest" delegate.