recaptcha image and curl + php

Question

$page = $curl->post($baseUrl.'/submit.php', array('url'=>$address,'phase'=>'1','randkey'=>$randKey[0],'id'=>'c_1'));
$exp = explode('recaptcha_image',$page);

The id recaptcha_image is not found although if i echo $page; the webpage will be displayed and surprisingly even the recpatcha div (with the image itself). Curl shouldn't load the image for recaptcha but somehow it does though when i try to find the div, it is not there. Is there a way to capture the url of the recaptcha image?

Answer 1

You'll want to use an HTML parser like this PHP Simple HTML DOM Parser. Something like this will work then:

<?php
$page = $curl->post($baseUrl.'/submit.php', array('url'=>$address,'phase'=>'1','randkey'=>$randKey[0],'id'=>'c_1'));
$html->load($page);
$ret = $html->find('script[src^=http://api.recaptcha.net/]',0);
$src = $ret->src;
//I'm not sure how you get an url with your library, so this might or might not work
$page = $curl->get($src);
preg_match("%challenge\ :\ '([a-zA-Z0-9-_]*)',%", $page, $matches);
$img = "http://api.recaptcha.net/image?c=".$matches[1];
?>

This first fetches the page, parses it for the script URL, then opens that URL for the challenge which is then appended to the URL itself. The image will be in the $img variable.