3 * API for easily embedding rich media such as videos and images into content.
10 public $handlers = array();
12 public $usecache = true;
13 public $linkifunknown = true;
16 * When an URL cannot be embedded, return false instead of returning a link
17 * or the URL. Bypasses the 'embed_maybe_make_link' filter.
19 public $return_false_on_fail = false;
24 public function __construct() {
25 // Hack to get the [embed] shortcode to run before wpautop()
26 add_filter( 'the_content', array( $this, 'run_shortcode' ), 8 );
28 // Shortcode placeholder for strip_shortcodes()
29 add_shortcode( 'embed', '__return_false' );
31 // Attempts to embed all URLs in a post
32 add_filter( 'the_content', array( $this, 'autoembed' ), 8 );
34 // After a post is saved, cache oEmbed items via AJAX
35 add_action( 'edit_form_advanced', array( $this, 'maybe_run_ajax_cache' ) );
39 * Process the [embed] shortcode.
41 * Since the [embed] shortcode needs to be run earlier than other shortcodes,
42 * this function removes all existing shortcodes, registers the [embed] shortcode,
43 * calls {@link do_shortcode()}, and then re-registers the old shortcodes.
45 * @uses $shortcode_tags
47 * @param string $content Content to parse
48 * @return string Content with shortcode parsed
50 public function run_shortcode( $content ) {
51 global $shortcode_tags;
53 // Back up current registered shortcodes and clear them all out
54 $orig_shortcode_tags = $shortcode_tags;
55 remove_all_shortcodes();
57 add_shortcode( 'embed', array( $this, 'shortcode' ) );
59 // Do the shortcode (only the [embed] one is registered)
60 $content = do_shortcode( $content );
62 // Put the original shortcodes back
63 $shortcode_tags = $orig_shortcode_tags;
69 * If a post/page was saved, then output JavaScript to make
70 * an AJAX request that will call WP_Embed::cache_oembed().
72 public function maybe_run_ajax_cache() {
75 if ( ! $post || empty( $_GET['message'] ) )
79 <script type="text/javascript">
81 jQuery(document).ready(function($){
82 $.get("<?php echo admin_url( 'admin-ajax.php?action=oembed-cache&post=' . $post->ID, 'relative' ); ?>");
90 * Register an embed handler. Do not use this function directly, use {@link wp_embed_register_handler()} instead.
91 * This function should probably also only be used for sites that do not support oEmbed.
93 * @param string $id An internal ID/name for the handler. Needs to be unique.
94 * @param string $regex The regex that will be used to see if this handler should be used for a URL.
95 * @param callback $callback The callback function that will be called if the regex is matched.
96 * @param int $priority Optional. Used to specify the order in which the registered handlers will be tested (default: 10). Lower numbers correspond with earlier testing, and handlers with the same priority are tested in the order in which they were added to the action.
98 public function register_handler( $id, $regex, $callback, $priority = 10 ) {
99 $this->handlers[$priority][$id] = array(
101 'callback' => $callback,
106 * Unregister a previously registered embed handler. Do not use this function directly, use {@link wp_embed_unregister_handler()} instead.
108 * @param string $id The handler ID that should be removed.
109 * @param int $priority Optional. The priority of the handler to be removed (default: 10).
111 public function unregister_handler( $id, $priority = 10 ) {
112 if ( isset($this->handlers[$priority][$id]) )
113 unset($this->handlers[$priority][$id]);
117 * The {@link do_shortcode()} callback function.
119 * Attempts to convert a URL into embed HTML. Starts by checking the URL against the regex of the registered embed handlers.
120 * If none of the regex matches and it's enabled, then the URL will be given to the {@link WP_oEmbed} class.
122 * @param array $attr {
123 * Shortcode attributes. Optional.
125 * @type int $width Width of the embed in pixels.
126 * @type int $height Height of the embed in pixels.
128 * @param string $url The URL attempting to be embedded.
129 * @return string The embed HTML on success, otherwise the original URL.
131 public function shortcode( $attr, $url = '' ) {
134 if ( empty( $url ) && ! empty( $attr['src'] ) ) {
142 $attr = wp_parse_args( $attr, wp_embed_defaults( $url ) );
144 // kses converts & into & and we need to undo this
145 // See https://core.trac.wordpress.org/ticket/11311
146 $url = str_replace( '&', '&', $url );
148 // Look for known internal handlers
149 ksort( $this->handlers );
150 foreach ( $this->handlers as $priority => $handlers ) {
151 foreach ( $handlers as $id => $handler ) {
152 if ( preg_match( $handler['regex'], $url, $matches ) && is_callable( $handler['callback'] ) ) {
153 if ( false !== $return = call_user_func( $handler['callback'], $matches, $attr, $url, $rawattr ) )
155 * Filter the returned embed handler.
159 * @see WP_Embed::shortcode()
161 * @param mixed $return The shortcode callback function to call.
162 * @param string $url The attempted embed URL.
163 * @param array $attr An array of shortcode attributes.
165 return apply_filters( 'embed_handler_html', $return, $url, $attr );
170 $post_ID = ( ! empty( $post->ID ) ) ? $post->ID : null;
171 if ( ! empty( $this->post_ID ) ) // Potentially set by WP_Embed::cache_oembed()
172 $post_ID = $this->post_ID;
174 // Unknown URL format. Let oEmbed have a go.
177 // Check for a cached result (stored in the post meta)
178 $key_suffix = md5( $url . serialize( $attr ) );
179 $cachekey = '_oembed_' . $key_suffix;
180 $cachekey_time = '_oembed_time_' . $key_suffix;
183 * Filter the oEmbed TTL value (time to live).
187 * @param int $time Time to live (in seconds).
188 * @param string $url The attempted embed URL.
189 * @param array $attr An array of shortcode attributes.
190 * @param int $post_ID Post ID.
192 $ttl = apply_filters( 'oembed_ttl', DAY_IN_SECONDS, $url, $attr, $post_ID );
194 $cache = get_post_meta( $post_ID, $cachekey, true );
195 $cache_time = get_post_meta( $post_ID, $cachekey_time, true );
197 if ( ! $cache_time ) {
201 $cached_recently = ( time() - $cache_time ) < $ttl;
203 if ( $this->usecache || $cached_recently ) {
204 // Failures are cached. Serve one if we're using the cache.
205 if ( '{{unknown}}' === $cache )
206 return $this->maybe_make_link( $url );
208 if ( ! empty( $cache ) ) {
210 * Filter the cached oEmbed HTML.
214 * @see WP_Embed::shortcode()
216 * @param mixed $cache The cached HTML result, stored in post meta.
217 * @param string $url The attempted embed URL.
218 * @param array $attr An array of shortcode attributes.
219 * @param int $post_ID Post ID.
221 return apply_filters( 'embed_oembed_html', $cache, $url, $attr, $post_ID );
226 * Filter whether to inspect the given URL for discoverable link tags.
230 * @see WP_oEmbed::discover()
232 * @param bool $enable Whether to enable `<link>` tag discovery. Default false.
234 $attr['discover'] = ( apply_filters( 'embed_oembed_discover', false ) && author_can( $post_ID, 'unfiltered_html' ) );
236 // Use oEmbed to get the HTML
237 $html = wp_oembed_get( $url, $attr );
239 // Maybe cache the result
241 update_post_meta( $post_ID, $cachekey, $html );
242 update_post_meta( $post_ID, $cachekey_time, time() );
243 } elseif ( ! $cache ) {
244 update_post_meta( $post_ID, $cachekey, '{{unknown}}' );
247 // If there was a result, return it
249 /** This filter is documented in wp-includes/class-wp-embed.php */
250 return apply_filters( 'embed_oembed_html', $html, $url, $attr, $post_ID );
255 return $this->maybe_make_link( $url );
259 * Delete all oEmbed caches. Unused by core as of 4.0.0.
261 * @param int $post_ID Post ID to delete the caches for.
263 public function delete_oembed_caches( $post_ID ) {
264 $post_metas = get_post_custom_keys( $post_ID );
265 if ( empty($post_metas) )
268 foreach( $post_metas as $post_meta_key ) {
269 if ( '_oembed_' == substr( $post_meta_key, 0, 8 ) )
270 delete_post_meta( $post_ID, $post_meta_key );
275 * Triggers a caching of all oEmbed results.
277 * @param int $post_ID Post ID to do the caching for.
279 public function cache_oembed( $post_ID ) {
280 $post = get_post( $post_ID );
282 $post_types = get_post_types( array( 'show_ui' => true ) );
284 * Filter the array of post types to cache oEmbed results for.
288 * @param array $post_types Array of post types to cache oEmbed results for. Defaults to post types with `show_ui` set to true.
290 if ( empty( $post->ID ) || ! in_array( $post->post_type, apply_filters( 'embed_cache_oembed_types', $post_types ) ) ){
295 if ( ! empty( $post->post_content ) ) {
296 $this->post_ID = $post->ID;
297 $this->usecache = false;
299 $content = $this->run_shortcode( $post->post_content );
300 $this->autoembed( $content );
302 $this->usecache = true;
307 * Passes any unlinked URLs that are on their own line to {@link WP_Embed::shortcode()} for potential embedding.
309 * @uses WP_Embed::autoembed_callback()
311 * @param string $content The content to be searched.
312 * @return string Potentially modified $content.
314 public function autoembed( $content ) {
315 return preg_replace_callback( '|^\s*(https?://[^\s"]+)\s*$|im', array( $this, 'autoembed_callback' ), $content );
319 * Callback function for {@link WP_Embed::autoembed()}.
321 * @param array $match A regex match array.
322 * @return string The embed HTML on success, otherwise the original URL.
324 public function autoembed_callback( $match ) {
325 $oldval = $this->linkifunknown;
326 $this->linkifunknown = false;
327 $return = $this->shortcode( array(), $match[1] );
328 $this->linkifunknown = $oldval;
330 return "\n$return\n";
334 * Conditionally makes a hyperlink based on an internal class variable.
336 * @param string $url URL to potentially be linked.
337 * @return false|string Linked URL or the original URL. False if 'return_false_on_fail' is true.
339 public function maybe_make_link( $url ) {
340 if ( $this->return_false_on_fail ) {
344 $output = ( $this->linkifunknown ) ? '<a href="' . esc_url($url) . '">' . esc_html($url) . '</a>' : $url;
347 * Filter the returned, maybe-linked embed URL.
351 * @param string $output The linked or original URL.
352 * @param string $url The original URL.
354 return apply_filters( 'embed_maybe_make_link', $output, $url );
357 $GLOBALS['wp_embed'] = new WP_Embed();