WP_Http_Curl

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.


Source

File: wp-includes/class-wp-http-curl.php

class WP_Http_Curl {

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

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

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

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

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

	/**
	 * Send a HTTP request to a URI using cURL extension.
	 *
	 * @since WP-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()
		);

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

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

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

		$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() );
			}
		}

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

		/*
		 * CURLOPT_TIMEOUT and CURLOPT_CONNECTTIMEOUT expect integers. Have to use ceil since.
		 * a value of 0 will allow an unlimited timeout.
		 */
		$timeout = (int) ceil( $r['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, ( $ssl_verify === true ) ? 2 : false );
		curl_setopt( $handle, CURLOPT_SSL_VERIFYPEER, $ssl_verify );

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

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

		/*
		 * The option doesn't work with safe mode or when open_basedir is set, and there's
		 * a bug https://core.trac.wordpress.org/ticket/17490 with redirected POST requests, so handle redirections outside Curl.
		 */
		curl_setopt( $handle, CURLOPT_FOLLOWLOCATION, false );
		if ( defined( 'CURLOPT_PROTOCOLS' ) ) // PHP 5.2.10 / cURL 7.19.4
			curl_setopt( $handle, CURLOPT_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS );

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

		if ( true === $r['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( $r['limit_response_size'] ) )
			$this->max_body_length = intval( $r['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 ( $r['stream'] ) {
			if ( ! WP_DEBUG )
				$this->stream_handle = @fopen( $r['filename'], 'w+' );
			else
				$this->stream_handle = fopen( $r['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()',
					$r['filename']
				) );
			}
		} else {
			$this->stream_handle = false;
		}

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

		if ( $r['httpversion'] == '1.0' )
			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 WP-2.8.0
		 *
		 * @param resource $handle  The cURL handle returned by curl_init() (passed by reference).
		 * @param array    $r       The HTTP request arguments.
		 * @param string   $url     The request URL.
		 */
		do_action_ref_array( 'http_api_curl', array( &$handle, $r, $url ) );

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

			if ( $curl_error = curl_error( $handle ) ) {
				curl_close( $handle );
				return new WP_Error( 'http_request_failed', $curl_error );
			}
			if ( in_array( curl_getinfo( $handle, CURLINFO_HTTP_CODE ), array( 301, 302 ) ) ) {
				curl_close( $handle );
				return new WP_Error( 'http_request_failed', __( 'Too many redirects.' ) );
			}

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

		curl_exec( $handle );
		$theHeaders = WP_Http::processHeaders( $this->headers, $url );
		$theBody = $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( $theBody ) && empty( $theHeaders['headers'] ) ) ) {
			if ( CURLE_WRITE_ERROR /* 23 */ == $curl_error ) {
				if ( ! $this->max_body_length || $this->max_body_length != $bytes_written_total ) {
					if ( $r['stream'] ) {
						curl_close( $handle );
						fclose( $this->stream_handle );
						return new WP_Error( 'http_request_failed', __( 'Failed to write request to temporary file.' ) );
					} else {
						curl_close( $handle );
						return new WP_Error( 'http_request_failed', curl_error( $handle ) );
					}
				}
			} else {
				if ( $curl_error = curl_error( $handle ) ) {
					curl_close( $handle );
					return new WP_Error( 'http_request_failed', $curl_error );
				}
			}
			if ( in_array( curl_getinfo( $handle, CURLINFO_HTTP_CODE ), array( 301, 302 ) ) ) {
				curl_close( $handle );
				return new WP_Error( 'http_request_failed', __( 'Too many redirects.' ) );
			}
		}

		curl_close( $handle );

		if ( $r['stream'] )
			fclose( $this->stream_handle );

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

		// Handle redirects.
		if ( false !== ( $redirect_response = WP_HTTP::handle_redirects( $url, $r, $response ) ) )
			return $redirect_response;

		if ( true === $r['decompress'] && true === WP_Http_Encoding::should_decode($theHeaders['headers']) )
			$theBody = WP_Http_Encoding::decompress( $theBody );

		$response['body'] = $theBody;

		return $response;
	}

	/**
	 * Grabs the headers of the cURL request.
	 *
	 * Each header is sent individually to this callback, so we append to the `$header` property
	 * for temporary storage
	 *
	 * @since WP-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, so we append 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 WP-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.
	 *
	 * @static
	 * @since WP-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 WP-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 );
	}
}

Methods

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

Changelog

Changelog
Version Description
WP-2.7.0 Introduced.