• Project page: http://www.google.com/recaptcha/
• Repository: https://github.com/google/recaptcha
• Version: 1.1.3
• License: BSD, see LICENSE

reCAPTCHA is a free CAPTCHA service that protect websites from spam and abuse. This is Google authored code that provides plugins for third-party integration with reCAPTCHA.

Composer is a widely used dependency manager for PHP packages. This reCAPTCHA client is available on Packagist as google/recaptcha and can be installed either by running the composer require command or adding the library to your composer.json. To enable Composer for you project, refer to the project's Getting Started documentation.

To add this dependency using the command, run the following from within your project directory:

composer require google/recaptcha "~1.1"

Alternatively, add the dependency directly to your composer.json file:

"require": {
    "google/recaptcha": "~1.1"
}

If you wish to install the library manually (i.e. without Composer), then you can use the links on the main project page to either clone the repo or download the ZIP file. For convenience, an autoloader script is provided in src/autoload.php which you can require into your script instead of Composer's vendor/autoload.php. For example:

require('/path/to/recaptcha/src/autoload.php');
$recaptcha = new \ReCaptcha\ReCaptcha($secret);

The classes in the project are structured according to the PSR-4 standard, so you may of course also use your own autoloader or require the needed files directly in your code.

If you would like to contribute to this project or run the unit tests on within your own environment you will need to install the development dependencies, in this case that means PHPUnit. If you clone the repo and run composer install from within the repo, this will also grab PHPUnit and all its dependencies for you. If you only need the autoloader installed, then you can always specify to Composer not to run in development mode, e.g. composer install --no-dev.

Note: These dependencies are only required for development, there's no requirement for them to be included in your production code.

First, register keys for your site at https://www.google.com/recaptcha/admin

When your app receives a form submission containing the g-recaptcha-response field, you can verify it using:

<?php
$recaptcha = new \ReCaptcha\ReCaptcha($secret);
$resp = $recaptcha->verify($gRecaptchaResponse, $remoteIp);
if ($resp->isSuccess()) {
    // verified!
    // if Domain Name Validation turned off don't forget to check hostname field
    // if($resp->getHostName() === $_SERVER['SERVER_NAME']) {  }
} else {
    $errors = $resp->getErrorCodes();
}

You can see an end-to-end working example in examples/example-captcha.php

The previous version of this client is still available on the 1.0.0 tag in this repo but it is purely for reference and will not receive any updates.

The major changes in 1.1.0 are:

• installation now via Composer;
• class loading also via Composer;
• classes now namespaced;
• old method call was $rc->verifyResponse($remoteIp, $response), new call is $rc->verify($response, $remoteIp)

We accept contributions via GitHub Pull Requests, but all contributors need to be covered by the standard Google Contributor License Agreement. You can find instructions for this in CONTRIBUTING