how to get raw post data of a form in a remote website using php

Question

I want to login to a remote website from mine. So, I used cURL to achieve this and I was successful using the code below:

function login($url,$data)
{
   $fp = fopen("cookie.txt", "w");
   fclose($fp);
   $login = curl_init();
   curl_setopt($login, CURLOPT_COOKIEJAR, "cookie.txt");
   curl_setopt($login, CURLOPT_COOKIEFILE, "cookie.txt");
   curl_setopt($login, CURLOPT_TIMEOUT, 40000);
   curl_setopt($login, CURLOPT_RETURNTRANSFER, TRUE);
   curl_setopt($login, CURLOPT_URL, $url);
   curl_setopt($login, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);
   curl_setopt($login, CURLOPT_FOLLOWLOCATION, TRUE);
   curl_setopt($login, CURLOPT_POST, TRUE);
   curl_setopt($login, CURLOPT_POSTFIELDS, $data);
   ob_start();
   return curl_exec ($login);
   ob_end_clean();
   curl_close ($login);
   unset($login);
}

So for posting data I used the raw data for the form in the website. Which I managed to get from developer tools in Edge. Here is the screenshot of raw POST data when I try to login directly in the remote website ( http://vce.ac.in )

The problem is the values of the parameters viewstate, validation, viewstategenerator are changing for every 24 hours.

So if there is a method in PHP to get the raw POST data of the website, I can update those values of raw data parameters which are changing.

Answer 1

Parse them with a simple PHP DOM

// get simple_html_dom.php from : https://netix.dl.sourceforge.net/project/simplehtmldom/simple_html_dom.php
require_once('simple_html_dom.php');

function login($url, $data){

   $html = file_get_html( $url );

   foreach ($html->find('input') as $input){
       # echo "INPUTDOM". print_r($input);
       if ($input->attr['name']=="__VIEWSTATE"){
           //__VIEWSTATE
           echo "__VIEWSTATE: {$input->attr['value']}\n";
           $form_data['__VIEWSTATE'] = $input->attr['value'];

       } elseif ($input->attr['name']=="__VIEWSTATEGENERATOR"){
           //__VIEWSTATEGENERATOR
           echo "__VIEWSTATEGENERATOR: {$input->attr['value']}\n";
           $form_data['__VIEWSTATEGENERATOR'] = $input->attr['value'];

       } elseif ($input->attr['name']=="__VIEWSTATE"){
           //__EVENTVALIDATION
           echo "__VIEWSTATE: {$input->attr['value']}\n";
           $form_data['__EVENTVALIDATION'] = $input->attr['value'];

       }
   };

   return $form_data;

}


echo login('http://vce.ac.in/index.aspx',['txtLoginID'=> 'user', 'txtPWD'=> 'password'] );