wp-includes/class-oembed.php

   1 <?php
   2 /**
   3  * API for fetching the HTML to embed remote content based on a provided URL
   4  *
   5  * Used internally by the WP_Embed class, but is designed to be generic.
   6  *
   7  * @link https://codex.wordpress.org/oEmbed oEmbed Codex Article
   8  * @link http://oembed.com/ oEmbed Homepage
   9  *
  10  * @package WordPress
  11  * @subpackage oEmbed
  12  */
  13
  14 /**
  15  * Core class used to implement oEmbed functionality.
  16  *
  17  * @since 2.9.0
  18  */
  19 class WP_oEmbed {
  20
  21         /**
  22          * A list of oEmbed providers.
  23          *
  24          * @since 2.9.0
  25          * @access public
  26          * @var array
  27          */
  28         public $providers = array();
  29
  30         /**
  31          * A list of an early oEmbed providers.
  32          *
  33          * @since 4.0.0
  34          * @access public
  35          * @static
  36          * @var array
  37          */
  38         public static $early_providers = array();
  39
  40         /**
  41          * A list of private/protected methods, used for backward compatibility.
  42          *
  43          * @since 4.2.0
  44          * @access private
  45          * @var array
  46          */
  47         private $compat_methods = array( '_fetch_with_format', '_parse_json', '_parse_xml', '_parse_body' );
  48
  49         /**
  50          * Constructor.
  51          *
  52          * @since 2.9.0
  53          * @access public
  54          */
  55         public function __construct() {
  56                 $host = urlencode( home_url() );
  57                 $providers = array(
  58                         '#http://((m|www)\.)?youtube\.com/watch.*#i'          => array( 'http://www.youtube.com/oembed',                             true  ),
  59                         '#https://((m|www)\.)?youtube\.com/watch.*#i'         => array( 'http://www.youtube.com/oembed?scheme=https',                true  ),
  60                         '#http://((m|www)\.)?youtube\.com/playlist.*#i'       => array( 'http://www.youtube.com/oembed',                             true  ),
  61                         '#https://((m|www)\.)?youtube\.com/playlist.*#i'      => array( 'http://www.youtube.com/oembed?scheme=https',                true  ),
  62                         '#http://youtu\.be/.*#i'                              => array( 'http://www.youtube.com/oembed',                             true  ),
  63                         '#https://youtu\.be/.*#i'                             => array( 'http://www.youtube.com/oembed?scheme=https',                true  ),
  64                         '#https?://(.+\.)?vimeo\.com/.*#i'                    => array( 'http://vimeo.com/api/oembed.{format}',                      true  ),
  65                         '#https?://(www\.)?dailymotion\.com/.*#i'             => array( 'https://www.dailymotion.com/services/oembed',               true  ),
  66                         '#https?://dai.ly/.*#i'                               => array( 'https://www.dailymotion.com/services/oembed',               true  ),
  67                         '#https?://(www\.)?flickr\.com/.*#i'                  => array( 'https://www.flickr.com/services/oembed/',                   true  ),
  68                         '#https?://flic\.kr/.*#i'                             => array( 'https://www.flickr.com/services/oembed/',                   true  ),
  69                         '#https?://(.+\.)?smugmug\.com/.*#i'                  => array( 'http://api.smugmug.com/services/oembed/',                   true  ),
  70                         '#https?://(www\.)?hulu\.com/watch/.*#i'              => array( 'http://www.hulu.com/api/oembed.{format}',                   true  ),
  71                         'http://i*.photobucket.com/albums/*'                  => array( 'http://api.photobucket.com/oembed',                         false ),
  72                         'http://gi*.photobucket.com/groups/*'                 => array( 'http://api.photobucket.com/oembed',                         false ),
  73                         '#https?://(www\.)?scribd\.com/doc/.*#i'              => array( 'http://www.scribd.com/services/oembed',                     true  ),
  74                         '#https?://wordpress.tv/.*#i'                         => array( 'http://wordpress.tv/oembed/',                               true  ),
  75                         '#https?://(.+\.)?polldaddy\.com/.*#i'                => array( 'https://polldaddy.com/oembed/',                             true  ),
  76                         '#https?://poll\.fm/.*#i'                             => array( 'https://polldaddy.com/oembed/',                             true  ),
  77                         '#https?://(www\.)?funnyordie\.com/videos/.*#i'       => array( 'http://www.funnyordie.com/oembed',                          true  ),
  78                         '#https?://(www\.)?twitter\.com/.+?/status(es)?/.*#i' => array( 'https://publish.twitter.com/oembed',                        true  ),
  79                         '#https?://(www\.)?twitter\.com/.+?/timelines/.*#i'   => array( 'https://publish.twitter.com/oembed',                        true  ),
  80                         '#https?://(www\.)?twitter\.com/i/moments/.*#i'       => array( 'https://publish.twitter.com/oembed',                        true  ),
  81                         '#https?://vine.co/v/.*#i'                            => array( 'https://vine.co/oembed.{format}',                           true  ),
  82                         '#https?://(www\.)?soundcloud\.com/.*#i'              => array( 'http://soundcloud.com/oembed',                              true  ),
  83                         '#https?://(.+?\.)?slideshare\.net/.*#i'              => array( 'https://www.slideshare.net/api/oembed/2',                   true  ),
  84                         '#https?://(www\.)?instagr(\.am|am\.com)/p/.*#i'      => array( 'https://api.instagram.com/oembed',                          true  ),
  85                         '#https?://(open|play)\.spotify\.com/.*#i'            => array( 'https://embed.spotify.com/oembed/',                         true  ),
  86                         '#https?://(.+\.)?imgur\.com/.*#i'                    => array( 'http://api.imgur.com/oembed',                               true  ),
  87                         '#https?://(www\.)?meetu(\.ps|p\.com)/.*#i'           => array( 'http://api.meetup.com/oembed',                              true  ),
  88                         '#https?://(www\.)?issuu\.com/.+/docs/.+#i'           => array( 'http://issuu.com/oembed_wp',                                true  ),
  89                         '#https?://(www\.)?collegehumor\.com/video/.*#i'      => array( 'http://www.collegehumor.com/oembed.{format}',               true  ),
  90                         '#https?://(www\.)?mixcloud\.com/.*#i'                => array( 'http://www.mixcloud.com/oembed',                            true  ),
  91                         '#https?://(www\.|embed\.)?ted\.com/talks/.*#i'       => array( 'http://www.ted.com/talks/oembed.{format}',                  true  ),
  92                         '#https?://(www\.)?(animoto|video214)\.com/play/.*#i' => array( 'https://animoto.com/oembeds/create',                        true  ),
  93                         '#https?://(.+)\.tumblr\.com/post/.*#i'               => array( 'https://www.tumblr.com/oembed/1.0',                         true  ),
  94                         '#https?://(www\.)?kickstarter\.com/projects/.*#i'    => array( 'https://www.kickstarter.com/services/oembed',               true  ),
  95                         '#https?://kck\.st/.*#i'                              => array( 'https://www.kickstarter.com/services/oembed',               true  ),
  96                         '#https?://cloudup\.com/.*#i'                         => array( 'https://cloudup.com/oembed',                                true  ),
  97                         '#https?://(www\.)?reverbnation\.com/.*#i'            => array( 'https://www.reverbnation.com/oembed',                       true  ),
  98                         '#https?://videopress.com/v/.*#'                      => array( 'https://public-api.wordpress.com/oembed/1.0/?for=' . $host, true  ),
  99                         '#https?://(www\.)?reddit\.com/r/[^/]+/comments/.*#i' => array( 'https://www.reddit.com/oembed',                             true  ),
 100                         '#https?://(www\.)?speakerdeck\.com/.*#i'             => array( 'https://speakerdeck.com/oembed.{format}',                   true  ),
 101                 );
 102
 103                 if ( ! empty( self::$early_providers['add'] ) ) {
 104                         foreach ( self::$early_providers['add'] as $format => $data ) {
 105                                 $providers[ $format ] = $data;
 106                         }
 107                 }
 108
 109                 if ( ! empty( self::$early_providers['remove'] ) ) {
 110                         foreach ( self::$early_providers['remove'] as $format ) {
 111                                 unset( $providers[ $format ] );
 112                         }
 113                 }
 114
 115                 self::$early_providers = array();
 116
 117                 /**
 118                  * Filters the list of whitelisted oEmbed providers.
 119                  *
 120                  * Since WordPress 4.4, oEmbed discovery is enabled for all users and allows embedding of sanitized
 121                  * iframes. The providers in this list are whitelisted, meaning they are trusted and allowed to
 122                  * embed any content, such as iframes, videos, JavaScript, and arbitrary HTML.
 123                  *
 124                  * Supported providers:
 125                  *
 126                  * |   Provider   |        Flavor         | Supports HTTPS |   Since   |
 127                  * | ------------ | --------------------- | :------------: | --------- |
 128                  * | Dailymotion  | dailymotion.com       |      Yes       | 2.9.0     |
 129                  * | Flickr       | flickr.com            |      Yes       | 2.9.0     |
 130                  * | Hulu         | hulu.com              |      Yes       | 2.9.0     |
 131                  * | Photobucket  | photobucket.com       |      No        | 2.9.0     |
 132                  * | Scribd       | scribd.com            |      Yes       | 2.9.0     |
 133                  * | Vimeo        | vimeo.com             |      Yes       | 2.9.0     |
 134                  * | WordPress.tv | wordpress.tv          |      Yes       | 2.9.0     |
 135                  * | YouTube      | youtube.com/watch     |      Yes       | 2.9.0     |
 136                  * | Funny or Die | funnyordie.com        |      Yes       | 3.0.0     |
 137                  * | Polldaddy    | polldaddy.com         |      Yes       | 3.0.0     |
 138                  * | SmugMug      | smugmug.com           |      Yes       | 3.0.0     |
 139                  * | YouTube      | youtu.be              |      Yes       | 3.0.0     |
 140                  * | Twitter      | twitter.com           |      Yes       | 3.4.0     |
 141                  * | Instagram    | instagram.com         |      Yes       | 3.5.0     |
 142                  * | Instagram    | instagr.am            |      Yes       | 3.5.0     |
 143                  * | Slideshare   | slideshare.net        |      Yes       | 3.5.0     |
 144                  * | SoundCloud   | soundcloud.com        |      Yes       | 3.5.0     |
 145                  * | Dailymotion  | dai.ly                |      Yes       | 3.6.0     |
 146                  * | Flickr       | flic.kr               |      Yes       | 3.6.0     |
 147                  * | Spotify      | spotify.com           |      Yes       | 3.6.0     |
 148                  * | Imgur        | imgur.com             |      Yes       | 3.9.0     |
 149                  * | Meetup.com   | meetup.com            |      Yes       | 3.9.0     |
 150                  * | Meetup.com   | meetu.ps              |      Yes       | 3.9.0     |
 151                  * | Animoto      | animoto.com           |      Yes       | 4.0.0     |
 152                  * | Animoto      | video214.com          |      Yes       | 4.0.0     |
 153                  * | CollegeHumor | collegehumor.com      |      Yes       | 4.0.0     |
 154                  * | Issuu        | issuu.com             |      Yes       | 4.0.0     |
 155                  * | Mixcloud     | mixcloud.com          |      Yes       | 4.0.0     |
 156                  * | Polldaddy    | poll.fm               |      Yes       | 4.0.0     |
 157                  * | TED          | ted.com               |      Yes       | 4.0.0     |
 158                  * | YouTube      | youtube.com/playlist  |      Yes       | 4.0.0     |
 159                  * | Vine         | vine.co               |      Yes       | 4.1.0     |
 160                  * | Tumblr       | tumblr.com            |      Yes       | 4.2.0     |
 161                  * | Kickstarter  | kickstarter.com       |      Yes       | 4.2.0     |
 162                  * | Kickstarter  | kck.st                |      Yes       | 4.2.0     |
 163                  * | Cloudup      | cloudup.com           |      Yes       | 4.4.0     |
 164                  * | ReverbNation | reverbnation.com      |      Yes       | 4.4.0     |
 165                  * | VideoPress   | videopress.com        |      Yes       | 4.4.0     |
 166                  * | Reddit       | reddit.com            |      Yes       | 4.4.0     |
 167                  * | Speaker Deck | speakerdeck.com       |      Yes       | 4.4.0     |
 168                  * | Twitter      | twitter.com/timelines |      Yes       | 4.5.0     |
 169                  * | Twitter      | twitter.com/moments   |      Yes       | 4.5.0     |
 170                  *
 171                  * No longer supported providers:
 172                  *
 173                  * |   Provider   |        Flavor        | Supports HTTPS |   Since   |  Removed  |
 174                  * | ------------ | -------------------- | :------------: | --------- | --------- |
 175                  * | Qik          | qik.com              |      Yes       | 2.9.0     | 3.9.0     |
 176                  * | Viddler      | viddler.com          |      Yes       | 2.9.0     | 4.0.0     |
 177                  * | Revision3    | revision3.com        |      No        | 2.9.0     | 4.2.0     |
 178                  * | Blip         | blip.tv              |      No        | 2.9.0     | 4.4.0     |
 179                  * | Rdio         | rdio.com             |      Yes       | 3.6.0     | 4.4.1     |
 180                  * | Rdio         | rd.io                |      Yes       | 3.6.0     | 4.4.1     |
 181                  *
 182                  * @see wp_oembed_add_provider()
 183                  *
 184                  * @since 2.9.0
 185                  *
 186                  * @param array $providers An array of popular oEmbed providers.
 187                  */
 188                 $this->providers = apply_filters( 'oembed_providers', $providers );
 189
 190                 // Fix any embeds that contain new lines in the middle of the HTML which breaks wpautop().
 191                 add_filter( 'oembed_dataparse', array($this, '_strip_newlines'), 10, 3 );
 192         }
 193
 194         /**
 195          * Exposes private/protected methods for backward compatibility.
 196          *
 197          * @since 4.0.0
 198          * @access public
 199          *
 200          * @param callable $name      Method to call.
 201          * @param array    $arguments Arguments to pass when calling.
 202          * @return mixed|bool Return value of the callback, false otherwise.
 203          */
 204         public function __call( $name, $arguments ) {
 205                 if ( in_array( $name, $this->compat_methods ) ) {
 206                         return call_user_func_array( array( $this, $name ), $arguments );
 207                 }
 208                 return false;
 209         }
 210
 211         /**
 212          * Takes a URL and returns the corresponding oEmbed provider's URL, if there is one.
 213          *
 214          * @since 4.0.0
 215          * @access public
 216          *
 217          * @see WP_oEmbed::discover()
 218          *
 219          * @param string        $url  The URL to the content.
 220          * @param string|array  $args Optional provider arguments.
 221          * @return false|string False on failure, otherwise the oEmbed provider URL.
 222          */
 223         public function get_provider( $url, $args = '' ) {
 224                 $args = wp_parse_args( $args );
 225
 226                 $provider = false;
 227
 228                 if ( !isset($args['discover']) )
 229                         $args['discover'] = true;
 230
 231                 foreach ( $this->providers as $matchmask => $data ) {
 232                         list( $providerurl, $regex ) = $data;
 233
 234                         // Turn the asterisk-type provider URLs into regex
 235                         if ( !$regex ) {
 236                                 $matchmask = '#' . str_replace( '___wildcard___', '(.+)', preg_quote( str_replace( '*', '___wildcard___', $matchmask ), '#' ) ) . '#i';
 237                                 $matchmask = preg_replace( '|^#http\\\://|', '#https?\://', $matchmask );
 238                         }
 239
 240                         if ( preg_match( $matchmask, $url ) ) {
 241                                 $provider = str_replace( '{format}', 'json', $providerurl ); // JSON is easier to deal with than XML
 242                                 break;
 243                         }
 244                 }
 245
 246                 if ( !$provider && $args['discover'] )
 247                         $provider = $this->discover( $url );
 248
 249                 return $provider;
 250         }
 251
 252         /**
 253          * Adds an oEmbed provider.
 254          *
 255          * The provider is removed just-in-time when wp_oembed_add_provider() is called before
 256          * the {@see 'plugins_loaded'} hook.
 257          *
 258          * The just-in-time addition is for the benefit of the {@see 'oembed_providers'} filter.
 259          *
 260          * @static
 261          * @since 4.0.0
 262          * @access public
 263          *
 264          * @see wp_oembed_add_provider()
 265          *
 266          * @param string $format   Format of URL that this provider can handle. You can use
 267          *                         asterisks as wildcards.
 268          * @param string $provider The URL to the oEmbed provider..
 269          * @param bool   $regex    Optional. Whether the $format parameter is in a regex format.
 270          *                         Default false.
 271          */
 272         public static function _add_provider_early( $format, $provider, $regex = false ) {
 273                 if ( empty( self::$early_providers['add'] ) ) {
 274                         self::$early_providers['add'] = array();
 275                 }
 276
 277                 self::$early_providers['add'][ $format ] = array( $provider, $regex );
 278         }
 279
 280         /**
 281          * Removes an oEmbed provider.
 282          *
 283          * The provider is removed just-in-time when wp_oembed_remove_provider() is called before
 284          * the {@see 'plugins_loaded'} hook.
 285          *
 286          * The just-in-time removal is for the benefit of the {@see 'oembed_providers'} filter.
 287          *
 288          * @since 4.0.0
 289          * @access public
 290          * @static
 291          *
 292          * @see wp_oembed_remove_provider()
 293          *
 294          * @param string $format The format of URL that this provider can handle. You can use
 295          *                       asterisks as wildcards.
 296          */
 297         public static function _remove_provider_early( $format ) {
 298                 if ( empty( self::$early_providers['remove'] ) ) {
 299                         self::$early_providers['remove'] = array();
 300                 }
 301
 302                 self::$early_providers['remove'][] = $format;
 303         }
 304
 305         /**
 306          * The do-it-all function that takes a URL and attempts to return the HTML.
 307          *
 308          * @see WP_oEmbed::fetch()
 309          * @see WP_oEmbed::data2html()
 310          *
 311          * @since 2.9.0
 312          * @access public
 313          *
 314          * @param string       $url  The URL to the content that should be attempted to be embedded.
 315          * @param array|string $args Optional. Arguments, usually passed from a shortcode. Default empty.
 316          * @return false|string False on failure, otherwise the UNSANITIZED (and potentially unsafe) HTML that should be used to embed.
 317          */
 318         public function get_html( $url, $args = '' ) {
 319                 $args = wp_parse_args( $args );
 320
 321                 /**
 322                  * Filters the oEmbed result before any HTTP requests are made.
 323                  *
 324                  * This allows one to short-circuit the default logic, perhaps by
 325                  * replacing it with a routine that is more optimal for your setup.
 326                  *
 327                  * Passing a non-null value to the filter will effectively short-circuit retrieval,
 328                  * returning the passed value instead.
 329                  *
 330                  * @since 4.5.3
 331                  *
 332                  * @param null|string $result The UNSANITIZED (and potentially unsafe) HTML that should be used to embed. Default null.
 333                  * @param string      $url    The URL to the content that should be attempted to be embedded.
 334                  * @param array       $args   Optional. Arguments, usually passed from a shortcode. Default empty.
 335                  */
 336                 $pre = apply_filters( 'pre_oembed_result', null, $url, $args );
 337
 338                 if ( null !== $pre ) {
 339                         return $pre;
 340                 }
 341
 342                 $provider = $this->get_provider( $url, $args );
 343
 344                 if ( ! $provider || false === $data = $this->fetch( $provider, $url, $args ) ) {
 345                         return false;
 346                 }
 347
 348                 /**
 349                  * Filters the HTML returned by the oEmbed provider.
 350                  *
 351                  * @since 2.9.0
 352                  *
 353                  * @param string $data The returned oEmbed HTML.
 354                  * @param string $url  URL of the content to be embedded.
 355                  * @param array  $args Optional arguments, usually passed from a shortcode.
 356                  */
 357                 return apply_filters( 'oembed_result', $this->data2html( $data, $url ), $url, $args );
 358         }
 359
 360         /**
 361          * Attempts to discover link tags at the given URL for an oEmbed provider.
 362          *
 363          * @since 2.9.0
 364          * @access public
 365          *
 366          * @param string $url The URL that should be inspected for discovery `<link>` tags.
 367          * @return false|string False on failure, otherwise the oEmbed provider URL.
 368          */
 369         public function discover( $url ) {
 370                 $providers = array();
 371                 $args = array(
 372                         'limit_response_size' => 153600, // 150 KB
 373                 );
 374
 375                 /**
 376                  * Filters oEmbed remote get arguments.
 377                  *
 378                  * @since 4.0.0
 379                  *
 380                  * @see WP_Http::request()
 381                  *
 382                  * @param array  $args oEmbed remote get arguments.
 383                  * @param string $url  URL to be inspected.
 384                  */
 385                 $args = apply_filters( 'oembed_remote_get_args', $args, $url );
 386
 387                 // Fetch URL content
 388                 $request = wp_safe_remote_get( $url, $args );
 389                 if ( $html = wp_remote_retrieve_body( $request ) ) {
 390
 391                         /**
 392                          * Filters the link types that contain oEmbed provider URLs.
 393                          *
 394                          * @since 2.9.0
 395                          *
 396                          * @param array $format Array of oEmbed link types. Accepts 'application/json+oembed',
 397                          *                      'text/xml+oembed', and 'application/xml+oembed' (incorrect,
 398                          *                      used by at least Vimeo).
 399                          */
 400                         $linktypes = apply_filters( 'oembed_linktypes', array(
 401                                 'application/json+oembed' => 'json',
 402                                 'text/xml+oembed' => 'xml',
 403                                 'application/xml+oembed' => 'xml',
 404                         ) );
 405
 406                         // Strip <body>
 407                         if ( $html_head_end = stripos( $html, '</head>' ) ) {
 408                                 $html = substr( $html, 0, $html_head_end );
 409                         }
 410
 411                         // Do a quick check
 412                         $tagfound = false;
 413                         foreach ( $linktypes as $linktype => $format ) {
 414                                 if ( stripos($html, $linktype) ) {
 415                                         $tagfound = true;
 416                                         break;
 417                                 }
 418                         }
 419
 420                         if ( $tagfound && preg_match_all( '#<link([^<>]+)/?>#iU', $html, $links ) ) {
 421                                 foreach ( $links[1] as $link ) {
 422                                         $atts = shortcode_parse_atts( $link );
 423
 424                                         if ( !empty($atts['type']) && !empty($linktypes[$atts['type']]) && !empty($atts['href']) ) {
 425                                                 $providers[$linktypes[$atts['type']]] = htmlspecialchars_decode( $atts['href'] );
 426
 427                                                 // Stop here if it's JSON (that's all we need)
 428                                                 if ( 'json' == $linktypes[$atts['type']] )
 429                                                         break;
 430                                         }
 431                                 }
 432                         }
 433                 }
 434
 435                 // JSON is preferred to XML
 436                 if ( !empty($providers['json']) )
 437                         return $providers['json'];
 438                 elseif ( !empty($providers['xml']) )
 439                         return $providers['xml'];
 440                 else
 441                         return false;
 442         }
 443
 444         /**
 445          * Connects to a oEmbed provider and returns the result.
 446          *
 447          * @since 2.9.0
 448          * @access public
 449          *
 450          * @param string       $provider The URL to the oEmbed provider.
 451          * @param string       $url      The URL to the content that is desired to be embedded.
 452          * @param array|string $args     Optional. Arguments, usually passed from a shortcode. Default empty.
 453          * @return false|object False on failure, otherwise the result in the form of an object.
 454          */
 455         public function fetch( $provider, $url, $args = '' ) {
 456                 $args = wp_parse_args( $args, wp_embed_defaults( $url ) );
 457
 458                 $provider = add_query_arg( 'maxwidth', (int) $args['width'], $provider );
 459                 $provider = add_query_arg( 'maxheight', (int) $args['height'], $provider );
 460                 $provider = add_query_arg( 'url', urlencode($url), $provider );
 461
 462                 /**
 463                  * Filters the oEmbed URL to be fetched.
 464                  *
 465                  * @since 2.9.0
 466                  *
 467                  * @param string $provider URL of the oEmbed provider.
 468                  * @param string $url      URL of the content to be embedded.
 469                  * @param array  $args     Optional arguments, usually passed from a shortcode.
 470                  */
 471                 $provider = apply_filters( 'oembed_fetch_url', $provider, $url, $args );
 472
 473                 foreach ( array( 'json', 'xml' ) as $format ) {
 474                         $result = $this->_fetch_with_format( $provider, $format );
 475                         if ( is_wp_error( $result ) && 'not-implemented' == $result->get_error_code() )
 476                                 continue;
 477                         return ( $result && ! is_wp_error( $result ) ) ? $result : false;
 478                 }
 479                 return false;
 480         }
 481
 482         /**
 483          * Fetches result from an oEmbed provider for a specific format and complete provider URL
 484          *
 485          * @since 3.0.0
 486          * @access private
 487          *
 488          * @param string $provider_url_with_args URL to the provider with full arguments list (url, maxheight, etc.)
 489          * @param string $format Format to use
 490          * @return false|object|WP_Error False on failure, otherwise the result in the form of an object.
 491          */
 492         private function _fetch_with_format( $provider_url_with_args, $format ) {
 493                 $provider_url_with_args = add_query_arg( 'format', $format, $provider_url_with_args );
 494
 495                 /** This filter is documented in wp-includes/class-oembed.php */
 496                 $args = apply_filters( 'oembed_remote_get_args', array(), $provider_url_with_args );
 497
 498                 $response = wp_safe_remote_get( $provider_url_with_args, $args );
 499                 if ( 501 == wp_remote_retrieve_response_code( $response ) )
 500                         return new WP_Error( 'not-implemented' );
 501                 if ( ! $body = wp_remote_retrieve_body( $response ) )
 502                         return false;
 503                 $parse_method = "_parse_$format";
 504                 return $this->$parse_method( $body );
 505         }
 506
 507         /**
 508          * Parses a json response body.
 509          *
 510          * @since 3.0.0
 511          * @access private
 512          *
 513          * @param string $response_body
 514          * @return object|false
 515          */
 516         private function _parse_json( $response_body ) {
 517                 $data = json_decode( trim( $response_body ) );
 518                 return ( $data && is_object( $data ) ) ? $data : false;
 519         }
 520
 521         /**
 522          * Parses an XML response body.
 523          *
 524          * @since 3.0.0
 525          * @access private
 526          *
 527          * @param string $response_body
 528          * @return object|false
 529          */
 530         private function _parse_xml( $response_body ) {
 531                 if ( ! function_exists( 'libxml_disable_entity_loader' ) )
 532                         return false;
 533
 534                 $loader = libxml_disable_entity_loader( true );
 535                 $errors = libxml_use_internal_errors( true );
 536
 537                 $return = $this->_parse_xml_body( $response_body );
 538
 539                 libxml_use_internal_errors( $errors );
 540                 libxml_disable_entity_loader( $loader );
 541
 542                 return $return;
 543         }
 544
 545         /**
 546          * Serves as a helper function for parsing an XML response body.
 547          *
 548          * @since 3.6.0
 549          * @access private
 550          *
 551          * @param string $response_body
 552          * @return object|false
 553          */
 554         private function _parse_xml_body( $response_body ) {
 555                 if ( ! function_exists( 'simplexml_import_dom' ) || ! class_exists( 'DOMDocument', false ) )
 556                         return false;
 557
 558                 $dom = new DOMDocument;
 559                 $success = $dom->loadXML( $response_body );
 560                 if ( ! $success )
 561                         return false;
 562
 563                 if ( isset( $dom->doctype ) )
 564                         return false;
 565
 566                 foreach ( $dom->childNodes as $child ) {
 567                         if ( XML_DOCUMENT_TYPE_NODE === $child->nodeType )
 568                                 return false;
 569                 }
 570
 571                 $xml = simplexml_import_dom( $dom );
 572                 if ( ! $xml )
 573                         return false;
 574
 575                 $return = new stdClass;
 576                 foreach ( $xml as $key => $value ) {
 577                         $return->$key = (string) $value;
 578                 }
 579
 580                 return $return;
 581         }
 582
 583         /**
 584          * Converts a data object from WP_oEmbed::fetch() and returns the HTML.
 585          *
 586          * @since 2.9.0
 587          * @access public
 588          *
 589          * @param object $data A data object result from an oEmbed provider.
 590          * @param string $url The URL to the content that is desired to be embedded.
 591          * @return false|string False on error, otherwise the HTML needed to embed.
 592          */
 593         public function data2html( $data, $url ) {
 594                 if ( ! is_object( $data ) || empty( $data->type ) )
 595                         return false;
 596
 597                 $return = false;
 598
 599                 switch ( $data->type ) {
 600                         case 'photo':
 601                                 if ( empty( $data->url ) || empty( $data->width ) || empty( $data->height ) )
 602                                         break;
 603                                 if ( ! is_string( $data->url ) || ! is_numeric( $data->width ) || ! is_numeric( $data->height ) )
 604                                         break;
 605
 606                                 $title = ! empty( $data->title ) && is_string( $data->title ) ? $data->title : '';
 607                                 $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>';
 608                                 break;
 609
 610                         case 'video':
 611                         case 'rich':
 612                                 if ( ! empty( $data->html ) && is_string( $data->html ) )
 613                                         $return = $data->html;
 614                                 break;
 615
 616                         case 'link':
 617                                 if ( ! empty( $data->title ) && is_string( $data->title ) )
 618                                         $return = '<a href="' . esc_url( $url ) . '">' . esc_html( $data->title ) . '</a>';
 619                                 break;
 620
 621                         default:
 622                                 $return = false;
 623                 }
 624
 625                 /**
 626                  * Filters the returned oEmbed HTML.
 627                  *
 628                  * Use this filter to add support for custom data types, or to filter the result.
 629                  *
 630                  * @since 2.9.0
 631                  *
 632                  * @param string $return The returned oEmbed HTML.
 633                  * @param object $data   A data object result from an oEmbed provider.
 634                  * @param string $url    The URL of the content to be embedded.
 635                  */
 636                 return apply_filters( 'oembed_dataparse', $return, $data, $url );
 637         }
 638
 639         /**
 640          * Strips any new lines from the HTML.
 641          *
 642          * @since 2.9.0 as strip_scribd_newlines()
 643          * @since 3.0.0
 644          * @access public
 645          *
 646          * @param string $html Existing HTML.
 647          * @param object $data Data object from WP_oEmbed::data2html()
 648          * @param string $url The original URL passed to oEmbed.
 649          * @return string Possibly modified $html
 650          */
 651         public function _strip_newlines( $html, $data, $url ) {
 652                 if ( false === strpos( $html, "\n" ) ) {
 653                         return $html;
 654                 }
 655
 656                 $count = 1;
 657                 $found = array();
 658                 $token = '__PRE__';
 659                 $search = array( "\t", "\n", "\r", ' ' );
 660                 $replace = array( '__TAB__', '__NL__', '__CR__', '__SPACE__' );
 661                 $tokenized = str_replace( $search, $replace, $html );
 662
 663                 preg_match_all( '#(<pre[^>]*>.+?</pre>)#i', $tokenized, $matches, PREG_SET_ORDER );
 664                 foreach ( $matches as $i => $match ) {
 665                         $tag_html = str_replace( $replace, $search, $match[0] );
 666                         $tag_token = $token . $i;
 667
 668                         $found[ $tag_token ] = $tag_html;
 669                         $html = str_replace( $tag_html, $tag_token, $html, $count );
 670                 }
 671
 672                 $replaced = str_replace( $replace, $search, $html );
 673                 $stripped = str_replace( array( "\r\n", "\n" ), '', $replaced );
 674                 $pre = array_values( $found );
 675                 $tokens = array_keys( $found );
 676
 677                 return str_replace( $tokens, $pre, $stripped );
 678         }
 679 }
 680
 681 /**
 682  * Returns the initialized WP_oEmbed object.
 683  *
 684  * @since 2.9.0
 685  * @access private
 686  *
 687  * @staticvar WP_oEmbed $wp_oembed
 688  *
 689  * @return WP_oEmbed object.
 690  */
 691 function _wp_oembed_get_object() {
 692         static $wp_oembed = null;
 693
 694         if ( is_null( $wp_oembed ) ) {
 695                 $wp_oembed = new WP_oEmbed();
 696         }
 697         return $wp_oembed;
 698 }