Recaptcha Request is returning Null - php

Question

I'm trying to implement this Recaptcha request into my sign-up form, however it isn't working. The cURL/JSON request returns null when I successfully validate the Recaptcha on my website.
I tried using var_dump on the "error-codes": from the JSON request, and it only returns null; whereas in this document it shows that it is clearly meant to output two items in the JSON request.
Thanks in advance, I haven't done much work with JSON/cURL, so be easy on me.
Here's my code:
PHP
<?php
if($_SERVER["REQUEST_METHOD"] == "POST") {
$recaptcha = $_POST['g-recaptcha-response'];
if(!empty($recaptcha)) {
function getCurlData($url) {
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($curl, CURLOPT_TIMEOUT, 10);
curl_setopt($curl, CURLOPT_USERAGENT, "Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.16) Gecko/20110319 Firefox/3.6.16");
$curlData = curl_exec($curl);
curl_close($curl);
return $curlData;
}
$google_url = "https://www.google.com/recaptcha/api/siteverify";
$secret = 'You will never know >:D';
$ip = $_SERVER['REMOTE_ADDR'];
$url = $google_url . "?secret=" . $secret . "&response=" . $recaptcha . "&remoteip=" . $ip;
$res = getCurlData($url);
$res = json_decode($res, true);
// var_dumping returns null
var_dump($res);
//reCaptcha success check
if($res['success'] == true) {
echo "Recaptcha was successfully validated";
} else {
echo "Recaptcha was not validated, please try again";
}
} else {
echo "You didn't validate the Recaptcha";
}
}
?>
HTML
<form action="home.php" method="post">
<div class="g-recaptcha" data-sitekey="I removed it for this post"></div>
<input class="btn btn-primary" type="submit" name="submit" value="SIGN UP" />
</form>

Answer 1

Here is my code running without problem:
Client Side:
<div class="g-recaptcha" data-sitekey="PUBLIC_KEY"></div>
Server Side:
if (isset($_POST['g-recaptcha-response'])) {
$captcha = $_POST['g-recaptcha-response'];
$privatekey = "SECRET_KEY";
$url = 'https://www.google.com/recaptcha/api/siteverify';
$data = array(
'secret' => $privatekey,
'response' => $captcha,
'remoteip' => $_SERVER['REMOTE_ADDR']
);
$curlConfig = array(
CURLOPT_URL => $url,
CURLOPT_POST => true,
CURLOPT_RETURNTRANSFER => true,
CURLOPT_POSTFIELDS => $data
);
$ch = curl_init();
curl_setopt_array($ch, $curlConfig);
$response = curl_exec($ch);
curl_close($ch);
}
$jsonResponse = json_decode($response);
if ($jsonResponse->success === true) {
doSomething();
}
else {
doSomeOtherThing();
}
Working here! :)

Answer 2

Your problem is probably with the SSL certificate.
You can put this line to let curl ignore it:
curl_setopt($ch,CURLOPT_SSL_VERIFYPEER, false)
However, you can put this to test on your localhost but when uploading your website, it is better to have an SSL certificate and this line removed.

Answer 3

Api says: METHOD: POST, you are sending "GET" request.
Check CURLOPT_POST and CURLOPT_POSTFIELDS option on http://php.net/manual/en/function.curl-setopt.php
EDIT:
I just checked the API, it work with GET too. I don't see any error in your code. Could you temporary change your function to:
function getCurlData($url) {
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($curl, CURLOPT_TIMEOUT, 10);
curl_setopt($curl, CURLOPT_USERAGENT, "Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.16) Gecko/20110319 Firefox/3.6.16");
$curlData = curl_exec($curl);
if (!$curlData) {
throw new \Exception('Curl error: ' . curl_error($curl));
}
curl_close($curl);
return $curlData;
}