Hi Andy - Here is a candidate for the mech FAQ:
I just discovered Tamper, a neat tool for Firefox which helps debugging mech problems. I think it will also be useful for people trying to figure out what a particular piece of javascript is doing. (This is probably old hat for most people out there, but it was news - and helpful - to me.)
Q: When I request a page, it works with my browser, but when I use mech, it doesn't. Why not?
A: Everything the web server knows about the client is passed back and forth using the HTTP protocol. This information includes the URI, GET and POST parameters, cookies, and other header information. If you can make mech send exactly the same information, then you should get exactly the same results. (I say "should" because there may be some timing issues as well - your mech program will normally run much faster than a human can click a browser and that may have an impact in some circumstances).
How do you find out what the browser sent? Well, you could sniff the network, but much easier is to use Firefox. Get the extension "Tamper". When activated, it keeps a log of all the http requests and responses, and allows you to examine the headers, cookies, parameters, etc. This is particularly useful when trying to figure out what some javascript does, because you can clearly see the results of script in terms of the parameters transmitted.
Cheers, Peter
