Set up an HTTP proxy to insert a header

I need to test some HTTP interaction with a client I'd rather not modify. What I need to test is the behavior of the server when the client's requests include a certain, static header.

I'm thinking the easiest way to run this test is to set up an HTTP proxy that inserts the header on every request. What would be the simplest way to set this up?

Solution 1:

I do something like this in my development environment by configuring Apache on port 80 as a proxy for my application server on port 8080, with the following Apache config:

NameVirtualHost *
<VirtualHost *>
   <Proxy http://127.0.0.1:8080/*>
      Allow from all
   </Proxy>
   <LocationMatch "/myapp">
      ProxyPass http://127.0.0.1:8080/myapp
      ProxyPassReverse http://127.0.0.1:8080/myapp
      Header add myheader "myvalue"
      RequestHeader set myheader "myvalue"   
   </LocationMatch>
</VirtualHost>

See LocationMatch and RequestHeader documentation.

This adds the header myheader: myvalue to requests going to the application server.

Solution 2:

You can also install Fiddler (http://www.fiddler2.com/fiddler2/) which is very easy to install (easier than Apache for example).

After launching it, it will register itself as system proxy. Then open the "Rules" menu, and choose "Customize Rules..." to open a JScript file which allow you to customize requests.

To add a custom header, just add a line in the OnBeforeRequest function:

oSession.oRequest.headers.Add("MyHeader", "MyValue");