google recaptcha implementation
<!DOCTYPE HTML>
<!– DO NOT FORGET TO CHANGE !YOUR_SECRET_KEY! to YOUR SECRET KEY FROM GOOGLE ADMIN CONSOLE – row 24 –>
<html>
<head>
<meta http-equiv=”Content-Type” content=”text/html; charset=UTF-8″ />
<meta name=”viewport” content=”width=device-width, initial-scale=1.0″>
<title>reCAPTCHA v2 | response</title>
</head>
<body>
<?php
foreach ($_POST as $key => $value) {
echo ‘key: ‘.$key.’ value: ‘.$value.'<br />’;
}
if(isset($_POST[‘g-recaptcha-response’])) {
$captcha = $_POST[‘g-recaptcha-response’];
}
if(!$captcha || empty($captcha)) {
echo ‘recaptcha verification failed’;
exit;
}
$secretKey = ‘!YOUR_SECRET_KEY!’;
$ip = $_SERVER[‘REMOTE_ADDR’];
$url = ‘https://www.google.com/recaptcha/api/siteverify?secret=’.urlencode($secretKey).’&response=’.urlencode($captcha);
$response = file_get_contents($url);
$responseKeys = json_decode($response, true);
if($responseKeys[“success”]) {
echo ‘captcha verification succesful’;
} else {
echo ‘Hello, robot!’;
}
?>
</body>
</html>
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv=”Content-Type” content=”text/html; charset=UTF-8″ />
<meta name=”viewport” content=”width=device-width, initial-scale=1.0″>
<title>reCAPTCHA v2 | response</title>
</head>
<body>
<?php
foreach ($_POST as $key => $value) {
echo ‘key: ‘.$key.’ value: ‘.$value.'<br />’;
}
if(isset($_POST[‘g-recaptcha-response’])) {
$captcha = $_POST[‘g-recaptcha-response’];
}
if(!$captcha || empty($captcha)) {
echo ‘recaptcha verification failed’;
exit;
}
$secretKey = ‘!YOUR_SECRET_KEY!’;
$ip = $_SERVER[‘REMOTE_ADDR’];
$url = ‘https://www.google.com/recaptcha/api/siteverify?secret=’.urlencode($secretKey).’&response=’.urlencode($captcha);
$response = file_get_contents($url);
$responseKeys = json_decode($response, true);
if($responseKeys[“success”]) {
echo ‘captcha verification successful’;
} else {
echo ‘Hello, robot!’;
}
?>
</body>
</html>
This code appears to be an HTML form with PHP code that implements Google reCAPTCHA v2 verification. reCAPTCHA is a service provided by Google that helps to prevent automated bots from submitting forms on websites. The purpose of this code is to validate whether the user filling out the form is a human or a robot.
Here’s a breakdown of the code:
DOCTYPE Declaration: This is a declaration specifying the type of HTML document. It’s not directly related to reCAPTCHA but indicates that the document is an HTML file.
<meta>tags are used to define metadata about the HTML document, such as character encoding and viewport settings.
- The
<title>tag sets the title of the web page.
- The
HTML Body:
- This section contains the main content of the web page.
PHP Code:
foreach ($_POST as $key => $value): This loop iterates through all the POST parameters sent to the server, which are likely the form fields submitted by the user. It then prints out the keys and values of these parameters.- The purpose of this loop seems to be for debugging or logging purposes, showing the values of all the form fields that were submitted.
reCAPTCHA Verification:
if(isset($_POST['g-recaptcha-response'])): This checks if the ‘g-recaptcha-response’ field is present in the POST data. This field contains the response token generated by reCAPTCHA when the user completes the reCAPTCHA challenge.
- The value of the ‘g-recaptcha-response’ field is assigned to the variable
$captcha.
- The value of the ‘g-recaptcha-response’ field is assigned to the variable
Cecking Captcha and Verification:
if(!$captcha || empty($captcha)): This checks if the$captchavariable is empty or not set. If it’s empty, it indicates that the user didn’t complete the reCAPTCHA challenge, and the script displays an error message and exits.
- The secret key for reCAPTCHA (
$secretKey) is set to a placeholder value (‘!YOUR_SECRET_KEY!’). This should be replaced with your actual reCAPTCHA secret key obtained from the Google Admin Console.
- The secret key for reCAPTCHA (
- The user’s IP address (
$ip) is obtained using$_SERVER['REMOTE_ADDR'].
- The user’s IP address (
Making the Verification Request:
- The script constructs a URL for making a request to Google’s reCAPTCHA verification endpoint using the provided secret key and the user’s response token.
- The
file_get_contents($url)function is used to make an HTTP request to the verification endpoint and retrieve the response.
- The
Parsing and Responding to Verification:
- The response from the reCAPTCHA verification endpoint is parsed using
json_decode().
- The response from the reCAPTCHA verification endpoint is parsed using
- If the
successfield in the response is true, it means the reCAPTCHA challenge was successfully completed, and the script displays a success message.
- If the
- If the
successfield is false, it means the challenge was failed, and the script displays a message indicating that a robot was detected.
- If the
HTML End:
The HTML and PHP code is closed with the </body> and </html> tags.
To use this code, you need to replace '!YOUR_SECRET_KEY!' with your actual reCAPTCHA secret key obtained from the Google Admin Console. You also need to integrate this code with a form submission process on your website. The purpose of reCAPTCHA is to prevent automated bots from submitting forms, so when a user submits the form, their response token is validated with Google’s servers to confirm they are not a bot.
