using cgi form via http and extracting results

[Ben Finney]

On Mon, 05 Jan 2004 17:39:30 -0800, Tim Roberts wrote:
> bmgx <bmgx_no_sp at mgleesonprop.co.za> wrote:
>>1) Make an http connection to the remote script (http://server/script.cgi)
>>2) Fill out the html form (1x TEXT and 2x SELECT input fields)
>>3) Submit the form
>>4) extract the actual returned result. (using regex or something..)
> 
> You don't actually need steps 1 and 2 at all.

True.

> HTTP transactions are all completely separate.

True (ignoring cookies for now).

> The results of a form submission are just a URL.

Usually false.

The result of most form submissions is an HTTP POST request, which
contains the URL and form content as separate data.

> If the form has fields "FromCurrency", "ToCurrency", and "Amount", all
> you have to do is this:
> 
> http://www.currencyservice.com?FromCurrency=dollars&ToCurrency=pounds&Amount=15

This is only true if the form action is an HTTP GET request, which is a
rather insecure and ugly way to submit form data, and makes it
impossible to submit many kinds of data.  HTTP POST is the recommended
method for submitting data to a CGI script.

> You don't have to HAVE the form source in order to submit a request.

True.  You just need to construct the HTTP POST request correctly.

-- 
 \          "It's a good thing we have gravity or else when birds died |
  `\             they'd just stay right up there. Hunters would be all |
_o__)                                     confused."  -- Steven Wright |
Ben Finney <http://bignose.squidly.org/>