java captcha

In a previous tutorial, we took a deep dive into the and I promised to show you how APIs can be consumed via the HTTP API in a WordPress plugin.

在上一教程中，我们深入研究了 ，我答应向您展示如何通过WordPress插件中的HTTP API来使用HTTP API 。

We’ve seen an example of a plugin using the HTTP API during the course of building a and in today’s tutorial, we will write a plugin that integrates a CAPTCHA with the WordPress login system using Google’s reCAPTCHA. And of course, the HTTP API will be used to send a POST request to reCAPTCHA to validate the user’s answer to the CAPTCHA challenge.

我们已经在构建的过程中看到了使用HTTP API的插件的示例，并且在今天的教程中，我们将编写一个插件，该插件使用Google的reCAPTCHA将CAPTCHA和WordPress登录系统集成在一起。 当然， HTTP API将用于向CAPTCHA发送POST请求，以验证用户对CAPTCHA挑战的回答。

Below is a screenshot of the default WordPress login form protected by a CAPTCHA on activation of the plugin to be developed during this tutorial.

以下是默认的WordPress登录表单的屏幕截图，该表单在激活本教程期间要开发的插件时受CAPTCHA保护。

插件开发 (Plugin Development)

Before we begin coding the plugin, head over to , register your domain name and grab your public and private API keys.

在我们开始对该插件进行编码之前，请转到 ，注册您的域名并获取您的public和private API密钥。

First off, include the plugin header.

首先，包括插件头。

Create a PHP class with two properties that will store your reCAPTCHA’s private and public key.

创建一个具有两个属性PHP类，该属性将存储reCAPTCHA的私钥和公钥。

class reCAPTCHA_Login_Form {    /** @type string private key|public key */    private $public_key, $private_key;

When writing WordPress plugins the way, all action and filter hooks should be in the constructor ( __construct ). Our plugin’s magic constructor method will consist of just two actions hooks that will add the CAPTCHA to the login form and validate the CAPTCHA response.

当以方式编写WordPress插件时，所有动作和过滤器挂钩都应在构造函数( __construct )中。 我们插件的魔术构造函数方法将仅包含两个动作钩子，这些钩子会将CAPTCHA添加到登录表单并验证CAPTCHA响应。

/** class constructor */    public function __construct() {        $this->public_key  = '6Le6d-USAAAAAFuYXiezgJh6rDaQFPKFEi84yfMc';        $this->private_key = '6Le6d-USAAAAAKvV-30YdZbdl4DVmg_geKyUxF6b';        // adds the captcha to the login form        add_action( 'login_form', array( $this, 'captcha_display' ) );        // authenticate the captcha answer        add_action( 'wp_authenticate_user', array( $this, 'validate_captcha_field' ), 10, 2 );    }

Code explanation: First, my reCAPTCHA public and private keys are saved to their class properties.

代码说明：首先，将我的reCAPTCHA公钥和私钥保存到其类属性中。

The captcha_display() method that will output the reCAPTCHA challenge is added to the WordPress login by the Action.

所述captcha_display()方法，该方法将输出reCAPTCHA验证被添加到由WordPress的登录动作。

The validate_captcha_field() method that will ensure – the CAPTCHA field isn’t left empty and also the answer is correct – is included to the login validation system by the Action.

操作将确保登录验证系统中包含的validate_captcha_field()方法validate_captcha_field() CAPTCHA字段不为空，并且答案正确)。

Below is the code for the captcha_display() and validate_captcha_field() method we talked about.

下面是我们讨论过的captcha_display()和validate_captcha_field()方法的代码。

/** Output the reCAPTCHA form field. */    public function captcha_display() {        ?>                
        
    

/**     * Verify the captcha answer     *     * @param $user string login username     * @param $password string login password     *     * @return WP_Error|WP_user     */    public function validate_captcha_field($user, $password) {        if ( ! isset( $_POST['recaptcha_response_field'] ) || empty( $_POST['recaptcha_response_field'] ) ) {            return new WP_Error( 'empty_captcha', 'CAPTCHA should not be empty');        }        if( isset( $_POST['recaptcha_response_field'] ) && $this->recaptcha_response() == 'false' ) {            return new WP_Error( 'invalid_captcha', 'CAPTCHA response was incorrect');        }        return $user;    }

Taking a closer look at the validate_captcha_field() precisely the second if conditional statement, a call is made to recaptcha_response() to check if the CAPTCHA answer is correct ( i.e. returns false if the CAPTCHA response is wrong).

仔细仔细地查看validate_captcha_field()的第二条if条件语句，调用recaptcha_response()来检查CAPTCHA答案是否正确(即，如果CAPTCHA响应错误，则返回false)。

Let’s see the code and explanation of recaptcha_response().

让我们看一下recaptcha_response()的代码和解释。

/**     * Get the reCAPTCHA API response.     *     * @return string     */    public function recaptcha_response() {        // reCAPTCHA challenge post data        $challenge = isset($_POST['recaptcha_challenge_field']) ? esc_attr($_POST['recaptcha_challenge_field']) : '';        // reCAPTCHA response post data        $response  = isset($_POST['recaptcha_response_field']) ? esc_attr($_POST['recaptcha_response_field']) : '';        $remote_ip = $_SERVER["REMOTE_ADDR"];        $post_body = array(            'privatekey' => $this->private_key,            'remoteip'   => $remote_ip,            'challenge'  => $challenge,            'response'   => $response        );        return $this->recaptcha_post_request( $post_body );    }

Code explanation: To verify that the CAPTCHA answer supplied by the user is correct, a POST request need to be sent to the endpoint http://www.google.com/recaptcha/api/verify with the following parameters or body.

代码说明：为了验证用户提供的验证码答案正确，需要使用以下参数或正文将POST请求发送到端点http://www.google.com/recaptcha/api/verify 。

• privatekey: Your private key

  privatekey ：您的私钥

• remoteip The IP address of the user who solved the CAPTCHA.

  remoteip解决了验证码的用户的IP地址。

• challenge The value of recaptcha_challenge_field sent via the form.

  challenge通过表单发送的recaptcha_challenge_field的值。

• response The value of recaptcha_response_field sent via the form.

  response通过表单发送的recaptcha_response_field的值。

First, the challenge and response POST data sent by the form is captured and saved to $challenge and $response respectively.

首先，捕获由表单发送的质询和响应POST数据，并将其分别保存到$challenge和$response 。

The IP address of the user is captured by $_SERVER["REMOTE_ADDR"] and save to $remote_ip.

用户的IP地址由$_SERVER["REMOTE_ADDR"]捕获并保存到$remote_ip 。

To send a POST request with the , the parameters or body should be array form as follows:

要使用发送POST请求，参数或正文应为数组形式，如下所示：

$post_body = array(            'privatekey' => $this->private_key,            'remoteip'   => $remote_ip,            'challenge'  => $challenge,            'response'   => $response        );

The POST parameters is passed as an argument to recaptcha_post_request() which will send the request along with the parameters to https://www.google.com/recaptcha/api/verify with the API response returned.

POST参数作为参数传递给recaptcha_post_request() ，它将与参数一起将请求连同参数一起发送到https://www.google.com/recaptcha/api/verify ，并返回API响应。

recaptcha_post_request() returns true if the CAPTCHA answer is correct and false otherwise.

如果验证码答案正确，则recaptcha_post_request()返回true否则返回false 。

Below is the code for recaptcha_post_request()

以下是recaptcha_post_request()的代码

/**     * Send HTTP POST request and return the response.     *     * @param $post_body array HTTP POST body     *     * @return bool     */    public function recaptcha_post_request( $post_body ) {        $args = array( 'body' => $post_body );        // make a POST request to the Google reCaptcha Server        $request = wp_remote_post( 'https://www.google.com/recaptcha/api/verify', $args );        // get the request response body        $response_body = wp_remote_retrieve_body( $request );        /**         * explode the response body and use the request_status         * @see https://developers.google.com/recaptcha/docs/verify         */        $answers = explode( "\n", $response_body );        $request_status = trim( $answers[0] );        return $request_status;    }

Code explanation: An array $args with the POST body $post_body save to the key body is created.

代码说明：将创建一个数组$args ，并将其POST正文$post_body保存到密钥body中。

The wp_remote_post send the POST request with the response save to $request.

wp_remote_post发送POST请求，并将响应保存到$request 。

The response body is retrieved by the wp_remote_retrieve_body and saved to $response_body.

响应正文由wp_remote_retrieve_body检索并保存到$response_body 。

If the captcha test was passed, the reCAPTCHA API returns:

如果验证码测试通过，则reCAPTCHA API返回：

truesuccess

Otherwise the following error is returned

否则返回以下错误

falseincorrect-captcha-sol

To get the recaptcha_post_request method to return a Boolean value i.e. true on success and false on failure; the response $response_body is and the array data with index 0 to remove any redundant white space from the beginning and end of the string.

为了让recaptcha_post_request返回一个布尔值，即，方法true的成功和false失败; 响应$response_body 并索引为0的数组数据，以删除字符串开头和结尾的任何多余空格。

Finally, we close the plugin class.

最后，我们关闭插件类。

} // reCAPTCHA_Login_Form

We are done coding the plugin class. To put the class to work, we need to instantiate it like so:

我们已经完成了插件类的编码。 为了使该类正常工作，我们需要像这样实例化它：

new reCAPTCHA_Login_Form();

结语 (Wrap Up)

If you wish to use the plugin on your WordPress site or to study the code in-depth, .

如果您想在WordPress网站上使用插件或深入研究代码，请 。

This is the second in a series that will demonstrate how the WordPress HTTP API is used in a plugin.

这是本系列的第二部分，将演示如何在插件中使用WordPress HTTP API。

Be sure to keep an eye on the WordPress channel for

请务必关注WordPress频道，以获取

Happy coding!

祝您编码愉快！

翻译自:

java captcha