Question

I want to set headers like post variable name and the value and send and expect response.
this is also a security question, assume I want to send post a form variables of which are action=”delete” and userid=100, and lets say, I have found a file which accepts ajax requests.

Answer 1

curl is your friend! 🙂

Say you’ve noticed an endpoint at example.org/process.php that a form is posting to. You can tailor you own custom request easily from the command line using curl.

$ curl -X POST --data "action=delete&userid=100" example.org/process.php

The --data or -D flag lets you pass arbitrary POST data just as an HTML form would. You can also set HTTP request headers with equal ease:

$ curl --header "User-Agent: Mosaic" example.org/process.php

You can see exactly what’s happening with the -v (for verbose) flag. For the first example above the output is:

* About to connect() to example.org port 80 (#0)
*   Trying 192.0.43.10... connected
* Connected to example.org (192.0.43.10) port 80 (#0)
> POST /process.php HTTP/1.1
> User-Agent: curl/7.21.6 (x86_64-apple-darwin10.5.0) libcurl/7.21.6 OpenSSL/1.0.0d zlib/1.2.5 libidn/1.22
> Host: example.org
> Accept: */*
> Content-Length: 24
> Content-Type: application/x-www-form-urlencoded
> 
* HTTP 1.0, assume close after body
< HTTP/1.0 302 Found
< Location: http://www.iana.org/domains/example/
< Server: BigIP
* HTTP/1.0 connection set to keep alive!
< Connection: Keep-Alive
< Content-Length: 0
< 
* Connection #0 to host example.org left intact
* Closing connection #0

If you’re using a *NIX operating system including Mac OS X, you probably already have curl, just open a shell. If you work with Ruby at all, I highly recommend curb, a set of bindings for that language. Most PHP installations come with curl support, although the interface is pretty horrible. The docs are over at php.net.