PHP and phpSpider: How to deal with website anti-crawler verification code mechanism?

PHP and phpSpider: How to deal with the website anti-crawler verification code mechanism?

In recent years, with the rapid development of the Internet, crawler technology has become increasingly mature. However, in order to protect the security and stability of their data, some websites have taken anti-crawler measures, the most common of which is the use of verification code mechanisms. In PHP development, phpSpider is a powerful crawler framework, but it also faces challenges when dealing with verification codes. This article will introduce how to use PHP and phpSpider to deal with the anti-crawler verification code mechanism of the website.

1. Obtain the verification code

First, we need to obtain the verification code. Typically, the verification code is an image returned through an HTTP request. In PHP, we can use the cURL library to send HTTP requests and the GD library to process verification code images.

The following sample code shows how to use the cURL library to send a request and obtain the verification code image:

$url = "http://www.example.com/captcha.php";
$curl = curl_init($url);

curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);

$response = curl_exec($curl);
curl_close($curl);

// 保存验证码图片
file_put_contents("captcha.jpg", $response);

2. Identify the verification code

Once we obtain the verification code image, continue Next, you need to identify it. In PHP, we can use the Tesseract OCR library to realize automatic recognition of verification codes.

The following example code shows how to use the Tesseract OCR library to identify verification code images:

exec("tesseract captcha.jpg captcha");

// 读取识别结果
$captcha = trim(file_get_contents("captcha.txt"));

3. Simulate user input

Through the above steps, we have obtained the verification code identification results. Next, we need to enter the recognition results into the verification code input box to pass the website's verification code verification.

The following sample code shows how to use phpSpider to simulate users entering verification codes:

// 创建爬虫实例
$spider = new phpspider();

// 设置验证码
$spider->on_handle_img = function ($obj, $data) {
    $obj->input->set_value("captcha", $captcha);
}

// 其他爬虫设置...
// ...

// 启动爬虫
$spider->start();

It should be noted that the name attribute of the website's verification code input box may change, and it needs to be changed according to the website's Make corresponding modifications according to specific circumstances.

4. Dealing with anti-crawler mechanisms

Some websites adopt more advanced anti-crawler mechanisms, such as setting specific parameters in the request header, or using JavaScript to generate dynamic verification codes. For these cases we need more complex processing.

The following example code shows how to set specific request header parameters to deal with the anti-crawler mechanism:

$url = "http://www.example.com";

$options = [
    'headers' => [
        'Referer: http://www.example.com/',
        'User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:43.0) Gecko/20100101 Firefox/43.0',
        // 其他特定参数...
    ],
];

$curl = curl_init($url);
curl_setopt_array($curl, $options);
$response = curl_exec($curl);
curl_close($curl);

// 处理响应结果

Needs to be modified and adjusted accordingly according to the anti-crawler mechanism of the specific website.

Conclusion

This article introduces how to use PHP and phpSpider to deal with the anti-crawler verification code mechanism of the website. By obtaining the verification code, identifying the verification code, and simulating the user to enter the verification code, we can effectively bypass the anti-crawler measures of the website. However, it should be noted that the use of crawler technology needs to comply with the rules and laws and regulations of the website to ensure the security and legality of the data.

The above is the detailed content of PHP and phpSpider: How to deal with website anti-crawler verification code mechanism?. For more information, please follow other related articles on the PHP Chinese website!