WordPress/wp-includes/class-oembed.php
2012-01-08 17:01:11 +00:00

294 lines
10 KiB
PHP

<?php
/**
* API for fetching the HTML to embed remote content based on a provided URL.
* Used internally by the {@link WP_Embed} class, but is designed to be generic.
*
* @link http://codex.wordpress.org/oEmbed oEmbed Codex Article
* @link http://oembed.com/ oEmbed Homepage
*
* @package WordPress
* @subpackage oEmbed
*/
/**
* oEmbed class.
*
* @package WordPress
* @subpackage oEmbed
* @since 2.9.0
*/
class WP_oEmbed {
var $providers = array();
/**
* Constructor
*
* @uses apply_filters() Filters a list of pre-defined oEmbed providers.
*/
function __construct() {
// List out some popular sites that support oEmbed.
// The WP_Embed class disables discovery for non-unfiltered_html users, so only providers in this array will be used for them.
// Add to this list using the wp_oembed_add_provider() function (see its PHPDoc for details).
$this->providers = apply_filters( 'oembed_providers', array(
'#http://(www\.)?youtube.com/watch.*#i' => array( 'http://www.youtube.com/oembed', true ),
'http://youtu.be/*' => array( 'http://www.youtube.com/oembed', false ),
'http://blip.tv/*' => array( 'http://blip.tv/oembed/', false ),
'#http://(www\.)?vimeo\.com/.*#i' => array( 'http://vimeo.com/api/oembed.{format}', true ),
'#http://(www\.)?dailymotion\.com/.*#i' => array( 'http://www.dailymotion.com/api/oembed', true ),
'#http://(www\.)?flickr\.com/.*#i' => array( 'http://www.flickr.com/services/oembed/', true ),
'#http://(.+\.)?smugmug\.com/.*#i' => array( 'http://api.smugmug.com/services/oembed/', true ),
'#http://(www\.)?hulu\.com/watch/.*#i' => array( 'http://www.hulu.com/api/oembed.{format}', true ),
'#http://(www\.)?viddler\.com/.*#i' => array( 'http://lab.viddler.com/services/oembed/', true ),
'http://qik.com/*' => array( 'http://qik.com/api/oembed.{format}', false ),
'http://revision3.com/*' => array( 'http://revision3.com/api/oembed/', false ),
'http://i*.photobucket.com/albums/*' => array( 'http://photobucket.com/oembed', false ),
'http://gi*.photobucket.com/groups/*' => array( 'http://photobucket.com/oembed', false ),
'#http://(www\.)?scribd\.com/.*#i' => array( 'http://www.scribd.com/services/oembed', true ),
'http://wordpress.tv/*' => array( 'http://wordpress.tv/oembed/', false ),
'#http://(.+\.)?polldaddy\.com/.*#i' => array( 'http://polldaddy.com/oembed/', true ),
'#http://(www\.)?funnyordie\.com/videos/.*#i' => array( 'http://www.funnyordie.com/oembed', true ),
) );
// Fix any embeds that contain new lines in the middle of the HTML which breaks wpautop().
add_filter( 'oembed_dataparse', array(&$this, '_strip_newlines'), 10, 3 );
}
/**
* The do-it-all function that takes a URL and attempts to return the HTML.
*
* @see WP_oEmbed::discover()
* @see WP_oEmbed::fetch()
* @see WP_oEmbed::data2html()
*
* @param string $url The URL to the content that should be attempted to be embedded.
* @param array $args Optional arguments. Usually passed from a shortcode.
* @return bool|string False on failure, otherwise the UNSANITIZED (and potentially unsafe) HTML that should be used to embed.
*/
function get_html( $url, $args = '' ) {
$provider = false;
if ( !isset($args['discover']) )
$args['discover'] = true;
foreach ( $this->providers as $matchmask => $data ) {
list( $providerurl, $regex ) = $data;
// Turn the asterisk-type provider URLs into regex
if ( !$regex )
$matchmask = '#' . str_replace( '___wildcard___', '(.+)', preg_quote( str_replace( '*', '___wildcard___', $matchmask ), '#' ) ) . '#i';
if ( preg_match( $matchmask, $url ) ) {
$provider = str_replace( '{format}', 'json', $providerurl ); // JSON is easier to deal with than XML
break;
}
}
if ( !$provider && $args['discover'] )
$provider = $this->discover( $url );
if ( !$provider || false === $data = $this->fetch( $provider, $url, $args ) )
return false;
return apply_filters( 'oembed_result', $this->data2html( $data, $url ), $url, $args );
}
/**
* Attempts to find oEmbed provider discovery <link> tags at the given URL.
*
* @param string $url The URL that should be inspected for discovery <link> tags.
* @return bool|string False on failure, otherwise the oEmbed provider URL.
*/
function discover( $url ) {
$providers = array();
// Fetch URL content
if ( $html = wp_remote_retrieve_body( wp_remote_get( $url ) ) ) {
// <link> types that contain oEmbed provider URLs
$linktypes = apply_filters( 'oembed_linktypes', array(
'application/json+oembed' => 'json',
'text/xml+oembed' => 'xml',
'application/xml+oembed' => 'xml', // Incorrect, but used by at least Vimeo
) );
// Strip <body>
$html = substr( $html, 0, stripos( $html, '</head>' ) );
// Do a quick check
$tagfound = false;
foreach ( $linktypes as $linktype => $format ) {
if ( stripos($html, $linktype) ) {
$tagfound = true;
break;
}
}
if ( $tagfound && preg_match_all( '/<link([^<>]+)>/i', $html, $links ) ) {
foreach ( $links[1] as $link ) {
$atts = shortcode_parse_atts( $link );
if ( !empty($atts['type']) && !empty($linktypes[$atts['type']]) && !empty($atts['href']) ) {
$providers[$linktypes[$atts['type']]] = $atts['href'];
// Stop here if it's JSON (that's all we need)
if ( 'json' == $linktypes[$atts['type']] )
break;
}
}
}
}
// JSON is preferred to XML
if ( !empty($providers['json']) )
return $providers['json'];
elseif ( !empty($providers['xml']) )
return $providers['xml'];
else
return false;
}
/**
* Connects to a oEmbed provider and returns the result.
*
* @param string $provider The URL to the oEmbed provider.
* @param string $url The URL to the content that is desired to be embedded.
* @param array $args Optional arguments. Usually passed from a shortcode.
* @return bool|object False on failure, otherwise the result in the form of an object.
*/
function fetch( $provider, $url, $args = '' ) {
$args = wp_parse_args( $args, wp_embed_defaults() );
$provider = add_query_arg( 'maxwidth', (int) $args['width'], $provider );
$provider = add_query_arg( 'maxheight', (int) $args['height'], $provider );
$provider = add_query_arg( 'url', urlencode($url), $provider );
foreach( array( 'json', 'xml' ) as $format ) {
$result = $this->_fetch_with_format( $provider, $format );
if ( is_wp_error( $result ) && 'not-implemented' == $result->get_error_code() )
continue;
return ( $result && ! is_wp_error( $result ) ) ? $result : false;
}
return false;
}
/**
* Fetches result from an oEmbed provider for a specific format and complete provider URL
*
* @since 3.0.0
* @access private
* @param string $provider_url_with_args URL to the provider with full arguments list (url, maxheight, etc.)
* @param string $format Format to use
* @return bool|object False on failure, otherwise the result in the form of an object.
*/
function _fetch_with_format( $provider_url_with_args, $format ) {
$provider_url_with_args = add_query_arg( 'format', $format, $provider_url_with_args );
$response = wp_remote_get( $provider_url_with_args );
if ( 501 == wp_remote_retrieve_response_code( $response ) )
return new WP_Error( 'not-implemented' );
if ( ! $body = wp_remote_retrieve_body( $response ) )
return false;
$parse_method = "_parse_$format";
return $this->$parse_method( $body );
}
/**
* Parses a json response body.
*
* @since 3.0.0
* @access private
*/
function _parse_json( $response_body ) {
return ( ( $data = json_decode( trim( $response_body ) ) ) && is_object( $data ) ) ? $data : false;
}
/**
* Parses an XML response body.
*
* @since 3.0.0
* @access private
*/
function _parse_xml( $response_body ) {
if ( function_exists('simplexml_load_string') ) {
$errors = libxml_use_internal_errors( 'true' );
$data = simplexml_load_string( $response_body );
libxml_use_internal_errors( $errors );
if ( is_object( $data ) )
return $data;
}
return false;
}
/**
* Converts a data object from {@link WP_oEmbed::fetch()} and returns the HTML.
*
* @param object $data A data object result from an oEmbed provider.
* @param string $url The URL to the content that is desired to be embedded.
* @return bool|string False on error, otherwise the HTML needed to embed.
*/
function data2html( $data, $url ) {
if ( !is_object($data) || empty($data->type) )
return false;
switch ( $data->type ) {
case 'photo':
if ( empty($data->url) || empty($data->width) || empty($data->height) )
return false;
$title = ( !empty($data->title) ) ? $data->title : '';
$return = '<a href="' . esc_url( $url ) . '"><img src="' . esc_url( $data->url ) . '" alt="' . esc_attr($title) . '" width="' . esc_attr($data->width) . '" height="' . esc_attr($data->height) . '" /></a>';
break;
case 'video':
case 'rich':
$return = ( !empty($data->html) ) ? $data->html : false;
break;
case 'link':
$return = ( !empty($data->title) ) ? '<a href="' . esc_url($url) . '">' . esc_html($data->title) . '</a>' : false;
break;
default;
$return = false;
}
// You can use this filter to add support for custom data types or to filter the result
return apply_filters( 'oembed_dataparse', $return, $data, $url );
}
/**
* Strip any new lines from the HTML.
*
* @access private
* @param string $html Existing HTML.
* @param object $data Data object from WP_oEmbed::data2html()
* @param string $url The original URL passed to oEmbed.
* @return string Possibly modified $html
*/
function _strip_newlines( $html, $data, $url ) {
if ( false !== strpos( $html, "\n" ) )
$html = str_replace( array( "\r\n", "\n" ), '', $html );
return $html;
}
}
/**
* Returns the initialized {@link WP_oEmbed} object
*
* @since 2.9.0
* @access private
*
* @see WP_oEmbed
* @uses WP_oEmbed
*
* @return WP_oEmbed object.
*/
function &_wp_oembed_get_object() {
static $wp_oembed;
if ( is_null($wp_oembed) )
$wp_oembed = new WP_oEmbed();
return $wp_oembed;
}