类文档

WP_Http_Curl

💡 云策文档标注

概述

WP_Http_Curl 是 WordPress 核心类,用于通过 cURL 扩展实现 HTTP 传输。它提供了发送 HTTP 请求、处理响应流和检测 cURL 可用性的方法,是 WP_Http 类的一部分。

关键要点

  • 核心功能:使用 cURL 扩展发送 HTTP 请求,支持 GET、POST、PUT 等多种方法,并处理代理、SSL 验证和重定向。
  • 依赖要求:需要服务器安装并启用 cURL 扩展,否则无法使用。
  • 主要方法:包括 request() 用于发送请求,stream_body() 和 stream_headers() 用于流式处理响应体与头,test() 用于检测 cURL 可用性。
  • 版本状态:自 WordPress 6.4.0 起已弃用,建议使用 WP_Http 类替代。

代码示例

// 示例:使用 WP_Http_Curl 发送请求
$http = new WP_Http_Curl();
$response = $http->request('https://example.com', array('method' => 'GET'));
if (!is_wp_error($response)) {
    echo $response['body'];
}

注意事项

  • 弃用警告:WP_Http_Curl 在 WordPress 6.4.0 中已弃用,开发者应迁移到 WP_Http 类以确保兼容性。
  • 错误处理:请求可能返回 WP_Error 对象,需检查错误状态。
  • 流式处理:支持将响应流式写入文件,需正确设置 stream 和 filename 参数。

📄 原文内容

Core class used to integrate Curl as an HTTP transport.

Description

HTTP request method uses Curl extension to retrieve the url.

Requires the Curl extension to be installed.

See also

Methods

Name Description
WP_Http_Curl::request Send a HTTP request to a URI using cURL extension.
WP_Http_Curl::stream_body Grabs the body of the cURL request.
WP_Http_Curl::stream_headers Grabs the headers of the cURL request.
WP_Http_Curl::test Determines whether this class can be used for retrieving a URL.

Source

class WP_Http_Curl {

	/**
	 * Temporary header storage for during requests.
	 *
	 * @since 3.2.0
	 * @var string
	 */
	private $headers = '';

	/**
	 * Temporary body storage for during requests.
	 *
	 * @since 3.6.0
	 * @var string
	 */
	private $body = '';

	/**
	 * The maximum amount of data to receive from the remote server.
	 *
	 * @since 3.6.0
	 * @var int|false
	 */
	private $max_body_length = false;

	/**
	 * The file resource used for streaming to file.
	 *
	 * @since 3.6.0
	 * @var resource|false
	 */
	private $stream_handle = false;

	/**
	 * The total bytes written in the current request.
	 *
	 * @since 4.1.0
	 * @var int
	 */
	private $bytes_written_total = 0;

	/**
	 * Send a HTTP request to a URI using cURL extension.
	 *
	 * @since 2.7.0
	 *
	 * @param string       $url  The request URL.
	 * @param string|array $args Optional. Override the defaults.
	 * @return array|WP_Error Array containing 'headers', 'body', 'response', 'cookies', 'filename'. A WP_Error instance upon error
	 */
	public function request( $url, $args = array() ) {
		$defaults = array(
			'method'      => 'GET',
			'timeout'     => 5,
			'redirection' => 5,
			'httpversion' => '1.0',
			'blocking'    => true,
			'headers'     => array(),
			'body'        => null,
			'cookies'     => array(),
			'decompress'  => false,
			'stream'      => false,
			'filename'    => null,
		);

		$parsed_args = wp_parse_args( $args, $defaults );

		if ( isset( $parsed_args['headers']['User-Agent'] ) ) {
			$parsed_args['user-agent'] = $parsed_args['headers']['User-Agent'];
			unset( $parsed_args['headers']['User-Agent'] );
		} elseif ( isset( $parsed_args['headers']['user-agent'] ) ) {
			$parsed_args['user-agent'] = $parsed_args['headers']['user-agent'];
			unset( $parsed_args['headers']['user-agent'] );
		}

		// Construct Cookie: header if any cookies are set.
		WP_Http::buildCookieHeader( $parsed_args );

		$handle = curl_init();

		// cURL offers really easy proxy support.
		$proxy = new WP_HTTP_Proxy();

		if ( $proxy->is_enabled() && $proxy->send_through_proxy( $url ) ) {

			curl_setopt( $handle, CURLOPT_PROXYTYPE, CURLPROXY_HTTP );
			curl_setopt( $handle, CURLOPT_PROXY, $proxy->host() );
			curl_setopt( $handle, CURLOPT_PROXYPORT, $proxy->port() );

			if ( $proxy->use_authentication() ) {
				curl_setopt( $handle, CURLOPT_PROXYAUTH, CURLAUTH_ANY );
				curl_setopt( $handle, CURLOPT_PROXYUSERPWD, $proxy->authentication() );
			}
		}

		$is_local   = isset( $parsed_args['local'] ) && $parsed_args['local'];
		$ssl_verify = isset( $parsed_args['sslverify'] ) && $parsed_args['sslverify'];
		if ( $is_local ) {
			/** This filter is documented in wp-includes/class-wp-http-streams.php */
			$ssl_verify = apply_filters( 'https_local_ssl_verify', $ssl_verify, $url );
		} elseif ( ! $is_local ) {
			/** This filter is documented in wp-includes/class-wp-http.php */
			$ssl_verify = apply_filters( 'https_ssl_verify', $ssl_verify, $url );
		}

		/*
		 * CURLOPT_TIMEOUT and CURLOPT_CONNECTTIMEOUT expect integers. Have to use ceil since.
		 * a value of 0 will allow an unlimited timeout.
		 */
		$timeout = (int) ceil( $parsed_args['timeout'] );
		curl_setopt( $handle, CURLOPT_CONNECTTIMEOUT, $timeout );
		curl_setopt( $handle, CURLOPT_TIMEOUT, $timeout );

		curl_setopt( $handle, CURLOPT_URL, $url );
		curl_setopt( $handle, CURLOPT_RETURNTRANSFER, true );
		curl_setopt( $handle, CURLOPT_SSL_VERIFYHOST, ( true === $ssl_verify ) ? 2 : false );
		curl_setopt( $handle, CURLOPT_SSL_VERIFYPEER, $ssl_verify );

		if ( $ssl_verify ) {
			curl_setopt( $handle, CURLOPT_CAINFO, $parsed_args['sslcertificates'] );
		}

		curl_setopt( $handle, CURLOPT_USERAGENT, $parsed_args['user-agent'] );

		/*
		 * The option doesn't work with safe mode or when open_basedir is set, and there's
		 * a bug #17490 with redirected POST requests, so handle redirections outside Curl.
		 */
		curl_setopt( $handle, CURLOPT_FOLLOWLOCATION, false );
		curl_setopt( $handle, CURLOPT_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS );

		switch ( $parsed_args['method'] ) {
			case 'HEAD':
				curl_setopt( $handle, CURLOPT_NOBODY, true );
				break;
			case 'POST':
				curl_setopt( $handle, CURLOPT_POST, true );
				curl_setopt( $handle, CURLOPT_POSTFIELDS, $parsed_args['body'] );
				break;
			case 'PUT':
				curl_setopt( $handle, CURLOPT_CUSTOMREQUEST, 'PUT' );
				curl_setopt( $handle, CURLOPT_POSTFIELDS, $parsed_args['body'] );
				break;
			default:
				curl_setopt( $handle, CURLOPT_CUSTOMREQUEST, $parsed_args['method'] );
				if ( ! is_null( $parsed_args['body'] ) ) {
					curl_setopt( $handle, CURLOPT_POSTFIELDS, $parsed_args['body'] );
				}
				break;
		}

		if ( true === $parsed_args['blocking'] ) {
			curl_setopt( $handle, CURLOPT_HEADERFUNCTION, array( $this, 'stream_headers' ) );
			curl_setopt( $handle, CURLOPT_WRITEFUNCTION, array( $this, 'stream_body' ) );
		}

		curl_setopt( $handle, CURLOPT_HEADER, false );

		if ( isset( $parsed_args['limit_response_size'] ) ) {
			$this->max_body_length = (int) $parsed_args['limit_response_size'];
		} else {
			$this->max_body_length = false;
		}

		// If streaming to a file open a file handle, and setup our curl streaming handler.
		if ( $parsed_args['stream'] ) {
			if ( ! WP_DEBUG ) {
				$this->stream_handle = @fopen( $parsed_args['filename'], 'w+' );
			} else {
				$this->stream_handle = fopen( $parsed_args['filename'], 'w+' );
			}
			if ( ! $this->stream_handle ) {
				return new WP_Error(
					'http_request_failed',
					sprintf(
						/* translators: 1: fopen(), 2: File name. */
						__( 'Could not open handle for %1$s to %2$s.' ),
						'fopen()',
						$parsed_args['filename']
					)
				);
			}
		} else {
			$this->stream_handle = false;
		}

		if ( ! empty( $parsed_args['headers'] ) ) {
			// cURL expects full header strings in each element.
			$headers = array();
			foreach ( $parsed_args['headers'] as $name => $value ) {
				$headers[] = "{$name}: $value";
			}
			curl_setopt( $handle, CURLOPT_HTTPHEADER, $headers );
		}

		if ( '1.0' === $parsed_args['httpversion'] ) {
			curl_setopt( $handle, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0 );
		} else {
			curl_setopt( $handle, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1 );
		}

		/**
		 * Fires before the cURL request is executed.
		 *
		 * Cookies are not currently handled by the HTTP API. This action allows
		 * plugins to handle cookies themselves.
		 *
		 * @since 2.8.0
		 *
		 * @param resource $handle      The cURL handle returned by curl_init() (passed by reference).
		 * @param array    $parsed_args The HTTP request arguments.
		 * @param string   $url         The request URL.
		 */
		do_action_ref_array( 'http_api_curl', array( &$handle, $parsed_args, $url ) );

		// We don't need to return the body, so don't. Just execute request and return.
		if ( ! $parsed_args['blocking'] ) {
			curl_exec( $handle );

			$curl_error = curl_error( $handle );

			if ( $curl_error ) {
				if ( PHP_VERSION_ID < 80000 ) { // curl_close() has no effect as of PHP 8.0.
					curl_close( $handle );
				}

				return new WP_Error( 'http_request_failed', $curl_error );
			}

			if ( in_array( curl_getinfo( $handle, CURLINFO_HTTP_CODE ), array( 301, 302 ), true ) ) {
				if ( PHP_VERSION_ID < 80000 ) { // curl_close() has no effect as of PHP 8.0.
					curl_close( $handle );
				}

				return new WP_Error( 'http_request_failed', __( 'Too many redirects.' ) );
			}

			if ( PHP_VERSION_ID < 80000 ) { // curl_close() has no effect as of PHP 8.0.
				curl_close( $handle );
			}

			return array(
				'headers'  => array(),
				'body'     => '',
				'response' => array(
					'code'    => false,
					'message' => false,
				),
				'cookies'  => array(),
			);
		}

		curl_exec( $handle );

		$processed_headers   = WP_Http::processHeaders( $this->headers, $url );
		$body                = $this->body;
		$bytes_written_total = $this->bytes_written_total;

		$this->headers             = '';
		$this->body                = '';
		$this->bytes_written_total = 0;

		$curl_error = curl_errno( $handle );

		// If an error occurred, or, no response.
		if ( $curl_error || ( 0 === strlen( $body ) && empty( $processed_headers['headers'] ) ) ) {
			if ( CURLE_WRITE_ERROR /* 23 */ === $curl_error ) {
				if ( ! $this->max_body_length || $this->max_body_length !== $bytes_written_total ) {
					if ( $parsed_args['stream'] ) {
						if ( PHP_VERSION_ID < 80000 ) { // curl_close() has no effect as of PHP 8.0.
							curl_close( $handle );
						}

						fclose( $this->stream_handle );

						return new WP_Error( 'http_request_failed', __( 'Failed to write request to temporary file.' ) );
					} else {
						if ( PHP_VERSION_ID < 80000 ) { // curl_close() has no effect as of PHP 8.0.
							curl_close( $handle );
						}

						return new WP_Error( 'http_request_failed', curl_error( $handle ) );
					}
				}
			} else {
				$curl_error = curl_error( $handle );

				if ( $curl_error ) {
					if ( PHP_VERSION_ID < 80000 ) { // curl_close() has no effect as of PHP 8.0.
						curl_close( $handle );
					}

					return new WP_Error( 'http_request_failed', $curl_error );
				}
			}

			if ( in_array( curl_getinfo( $handle, CURLINFO_HTTP_CODE ), array( 301, 302 ), true ) ) {
				if ( PHP_VERSION_ID < 80000 ) { // curl_close() has no effect as of PHP 8.0.
					curl_close( $handle );
				}

				return new WP_Error( 'http_request_failed', __( 'Too many redirects.' ) );
			}
		}

		if ( PHP_VERSION_ID < 80000 ) { // curl_close() has no effect as of PHP 8.0.
			curl_close( $handle );
		}

		if ( $parsed_args['stream'] ) {
			fclose( $this->stream_handle );
		}

		$response = array(
			'headers'  => $processed_headers['headers'],
			'body'     => null,
			'response' => $processed_headers['response'],
			'cookies'  => $processed_headers['cookies'],
			'filename' => $parsed_args['filename'],
		);

		// Handle redirects.
		$redirect_response = WP_Http::handle_redirects( $url, $parsed_args, $response );
		if ( false !== $redirect_response ) {
			return $redirect_response;
		}

		if ( true === $parsed_args['decompress']
			&& true === WP_Http_Encoding::should_decode( $processed_headers['headers'] )
		) {
			$body = WP_Http_Encoding::decompress( $body );
		}

		$response['body'] = $body;

		return $response;
	}

	/**
	 * Grabs the headers of the cURL request.
	 *
	 * Each header is sent individually to this callback, and is appended to the `$header` property
	 * for temporary storage.
	 *
	 * @since 3.2.0
	 *
	 * @param resource $handle  cURL handle.
	 * @param string   $headers cURL request headers.
	 * @return int Length of the request headers.
	 */
	private function stream_headers( $handle, $headers ) {
		$this->headers .= $headers;
		return strlen( $headers );
	}

	/**
	 * Grabs the body of the cURL request.
	 *
	 * The contents of the document are passed in chunks, and are appended to the `$body`
	 * property for temporary storage. Returning a length shorter than the length of
	 * `$data` passed in will cause cURL to abort the request with `CURLE_WRITE_ERROR`.
	 *
	 * @since 3.6.0
	 *
	 * @param resource $handle cURL handle.
	 * @param string   $data   cURL request body.
	 * @return int Total bytes of data written.
	 */
	private function stream_body( $handle, $data ) {
		$data_length = strlen( $data );

		if ( $this->max_body_length && ( $this->bytes_written_total + $data_length ) > $this->max_body_length ) {
			$data_length = ( $this->max_body_length - $this->bytes_written_total );
			$data        = substr( $data, 0, $data_length );
		}

		if ( $this->stream_handle ) {
			$bytes_written = fwrite( $this->stream_handle, $data );
		} else {
			$this->body   .= $data;
			$bytes_written = $data_length;
		}

		$this->bytes_written_total += $bytes_written;

		// Upon event of this function returning less than strlen( $data ) curl will error with CURLE_WRITE_ERROR.
		return $bytes_written;
	}

	/**
	 * Determines whether this class can be used for retrieving a URL.
	 *
	 * @since 2.7.0
	 *
	 * @param array $args Optional. Array of request arguments. Default empty array.
	 * @return bool False means this class can not be used, true means it can.
	 */
	public static function test( $args = array() ) {
		if ( ! function_exists( 'curl_init' ) || ! function_exists( 'curl_exec' ) ) {
			return false;
		}

		$is_ssl = isset( $args['ssl'] ) && $args['ssl'];

		if ( $is_ssl ) {
			$curl_version = curl_version();
			// Check whether this cURL version support SSL requests.
			if ( ! ( CURL_VERSION_SSL & $curl_version['features'] ) ) {
				return false;
			}
		}

		/**
		 * Filters whether cURL can be used as a transport for retrieving a URL.
		 *
		 * @since 2.7.0
		 *
		 * @param bool  $use_class Whether the class can be used. Default true.
		 * @param array $args      An array of request arguments.
		 */
		return apply_filters( 'use_curl_transport', true, $args );
	}
}

Changelog

Version Description
6.4.0 Deprecated. Use WP_Http
2.7.0 Introduced.