WordPress/wp-includes/default-filters.php

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<?php
/**
* Sets up the default filters and actions for most
* of the WordPress hooks.
*
* If you need to remove a default hook, this file will
* give you the priority for which to use to remove the
* hook.
*
* Not all of the default hooks are found in default-filters.php
*
* @package WordPress
*/
// Strip, trim, kses, special chars for string saves
foreach ( array( 'pre_term_name', 'pre_comment_author_name', 'pre_link_name', 'pre_link_target', 'pre_link_rel', 'pre_user_display_name', 'pre_user_first_name', 'pre_user_last_name', 'pre_user_nickname' ) as $filter ) {
add_filter( $filter, 'sanitize_text_field' );
add_filter( $filter, 'wp_filter_kses' );
add_filter( $filter, '_wp_specialchars', 30 );
}
// Strip, kses, special chars for string display
foreach ( array( 'term_name', 'comment_author_name', 'link_name', 'link_target', 'link_rel', 'user_display_name', 'user_first_name', 'user_last_name', 'user_nickname' ) as $filter ) {
if ( is_admin() ) {
// These are expensive. Run only on admin pages for defense in depth.
add_filter( $filter, 'sanitize_text_field' );
add_filter( $filter, 'wp_kses_data' );
}
add_filter( $filter, '_wp_specialchars', 30 );
}
// Kses only for textarea saves
foreach ( array( 'pre_term_description', 'pre_link_description', 'pre_link_notes', 'pre_user_description' ) as $filter ) {
add_filter( $filter, 'wp_filter_kses' );
}
// Kses only for textarea admin displays
if ( is_admin() ) {
foreach ( array( 'term_description', 'link_description', 'link_notes', 'user_description' ) as $filter ) {
add_filter( $filter, 'wp_kses_data' );
}
add_filter( 'comment_text', 'wp_kses_post' );
}
// Email saves
foreach ( array( 'pre_comment_author_email', 'pre_user_email' ) as $filter ) {
add_filter( $filter, 'trim' );
add_filter( $filter, 'sanitize_email' );
add_filter( $filter, 'wp_filter_kses' );
}
// Email admin display
foreach ( array( 'comment_author_email', 'user_email' ) as $filter ) {
add_filter( $filter, 'sanitize_email' );
if ( is_admin() )
add_filter( $filter, 'wp_kses_data' );
}
// Save URL
foreach ( array( 'pre_comment_author_url', 'pre_user_url', 'pre_link_url', 'pre_link_image',
'pre_link_rss', 'pre_post_guid' ) as $filter ) {
add_filter( $filter, 'wp_strip_all_tags' );
add_filter( $filter, 'esc_url_raw' );
add_filter( $filter, 'wp_filter_kses' );
}
// Display URL
foreach ( array( 'user_url', 'link_url', 'link_image', 'link_rss', 'comment_url', 'post_guid' ) as $filter ) {
if ( is_admin() )
add_filter( $filter, 'wp_strip_all_tags' );
add_filter( $filter, 'esc_url' );
if ( is_admin() )
add_filter( $filter, 'wp_kses_data' );
}
// Slugs
add_filter( 'pre_term_slug', 'sanitize_title' );
// Keys
foreach ( array( 'pre_post_type', 'pre_post_status', 'pre_post_comment_status', 'pre_post_ping_status' ) as $filter ) {
add_filter( $filter, 'sanitize_key' );
}
// Mime types
add_filter( 'pre_post_mime_type', 'sanitize_mime_type' );
add_filter( 'post_mime_type', 'sanitize_mime_type' );
// Places to balance tags on input
foreach ( array( 'content_save_pre', 'excerpt_save_pre', 'comment_save_pre', 'pre_comment_content' ) as $filter ) {
add_filter( $filter, 'convert_invalid_entities' );
add_filter( $filter, 'balanceTags', 50 );
}
// Format strings for display.
foreach ( array( 'comment_author', 'term_name', 'link_name', 'link_description', 'link_notes', 'bloginfo', 'wp_title', 'widget_title' ) as $filter ) {
add_filter( $filter, 'wptexturize' );
add_filter( $filter, 'convert_chars' );
add_filter( $filter, 'esc_html' );
}
// Format WordPress
foreach ( array( 'the_content', 'the_title', 'wp_title' ) as $filter )
add_filter( $filter, 'capital_P_dangit', 11 );
add_filter( 'comment_text', 'capital_P_dangit', 31 );
// Format titles
foreach ( array( 'single_post_title', 'single_cat_title', 'single_tag_title', 'single_month_title', 'nav_menu_attr_title', 'nav_menu_description' ) as $filter ) {
add_filter( $filter, 'wptexturize' );
add_filter( $filter, 'strip_tags' );
}
// Format text area for display.
foreach ( array( 'term_description' ) as $filter ) {
add_filter( $filter, 'wptexturize' );
add_filter( $filter, 'convert_chars' );
add_filter( $filter, 'wpautop' );
add_filter( $filter, 'shortcode_unautop');
}
// Format for RSS
add_filter( 'term_name_rss', 'convert_chars' );
// Pre save hierarchy
add_filter( 'wp_insert_post_parent', 'wp_check_post_hierarchy_for_loops', 10, 2 );
add_filter( 'wp_update_term_parent', 'wp_check_term_hierarchy_for_loops', 10, 3 );
// Display filters
add_filter( 'the_title', 'wptexturize' );
add_filter( 'the_title', 'convert_chars' );
add_filter( 'the_title', 'trim' );
Merge the Responsive Images feature plugin into core, initial commit. See: https://github.com/ResponsiveImagesCG/wp-tevko-responsive-images/ New functions in `media.php`: * `wp_get_attachment_image_srcset_array()` - Returns an array of image candidate string data used to build a `srcset` value for an attachment given an `$attachement_id` and `$size`. * `wp_get_attachment_image_srcset()` - Returns the `srcset` value for an attachment given an `$attachement_id` and `$size`. * `wp_get_attachment_image_sizes()` - Returns the `sizes` value for an attachment given an `$attachement_id` and `$size` and optional arguments used to alter its output. * `wp_make_content_images_responsive()` - A display filter for adding `srcset` and `sizes` to images embedded in content. * `wp_img_add_srcset_and_sizes()` - A utility function used by `wp_make_content_images_responsive()` to add `srcset` and `sizes` to a single `<img>` element. Modifies existing core functions: * Modify `wp_get_attachment_image()` so the HTML returned for an image includes `srcset` and `sizes`. * Modify `get_media_embedded_in_content()` (sup, 3.6 leftover) by adding `<img>` to the list of accepted tags that can be matched in content. This is used in `wp_make_content_images_responsive()` to find all of the images embedded in content before passing them off to `wp_img_add_srcset_and_sizes()`. Tests: * Add a new factory method to `WP_UnitTest_Factory_For_Attachment` named `create_upload_object()` * Adds unit tests * Updates unit tests Props joemcgill, tevko, jaspermdegroot, mdmcginn, barryceelen, peterwilsoncc, fsylum, wonderboymusic, chriscoyier, benjaminpick, jrfnl, #12kingkool68, janhenckens, ryanmarkel, side777, ryelle, wturrell, micahmills, mattbagwell, coliff, DrewAPicture. See #33641. Built from https://develop.svn.wordpress.org/trunk@34855 git-svn-id: http://core.svn.wordpress.org/trunk@34820 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-10-06 06:59:24 +02:00
add_filter( 'the_content', 'wptexturize' );
add_filter( 'the_content', 'convert_smilies' );
add_filter( 'the_content', 'convert_chars' );
add_filter( 'the_content', 'wpautop' );
add_filter( 'the_content', 'shortcode_unautop' );
add_filter( 'the_content', 'prepend_attachment' );
add_filter( 'the_content', 'wp_make_content_images_responsive' );
add_filter( 'the_excerpt', 'wptexturize' );
add_filter( 'the_excerpt', 'convert_smilies' );
add_filter( 'the_excerpt', 'convert_chars' );
add_filter( 'the_excerpt', 'wpautop' );
add_filter( 'the_excerpt', 'shortcode_unautop');
add_filter( 'get_the_excerpt', 'wp_trim_excerpt' );
add_filter( 'comment_text', 'wptexturize' );
add_filter( 'comment_text', 'convert_chars' );
add_filter( 'comment_text', 'make_clickable', 9 );
add_filter( 'comment_text', 'force_balance_tags', 25 );
add_filter( 'comment_text', 'convert_smilies', 20 );
add_filter( 'comment_text', 'wpautop', 30 );
add_filter( 'comment_excerpt', 'convert_chars' );
add_filter( 'list_cats', 'wptexturize' );
add_filter( 'wp_sprintf', 'wp_sprintf_l', 10, 2 );
// RSS filters
add_filter( 'the_title_rss', 'strip_tags' );
add_filter( 'the_title_rss', 'ent2ncr', 8 );
add_filter( 'the_title_rss', 'esc_html' );
add_filter( 'the_content_rss', 'ent2ncr', 8 );
add_filter( 'the_content_feed', 'wp_staticize_emoji' );
add_filter( 'the_excerpt_rss', 'convert_chars' );
add_filter( 'the_excerpt_rss', 'ent2ncr', 8 );
add_filter( 'comment_author_rss', 'ent2ncr', 8 );
add_filter( 'comment_text_rss', 'ent2ncr', 8 );
add_filter( 'comment_text_rss', 'esc_html' );
add_filter( 'comment_text_rss', 'wp_staticize_emoji' );
add_filter( 'bloginfo_rss', 'ent2ncr', 8 );
add_filter( 'the_author', 'ent2ncr', 8 );
add_filter( 'the_guid', 'esc_url' );
// Email filters
add_filter( 'wp_mail', 'wp_staticize_emoji_for_email' );
// Misc filters
add_filter( 'option_ping_sites', 'privacy_ping_filter' );
add_filter( 'option_blog_charset', '_wp_specialchars' ); // IMPORTANT: This must not be wp_specialchars() or esc_html() or it'll cause an infinite loop
add_filter( 'option_blog_charset', '_canonical_charset' );
add_filter( 'option_home', '_config_wp_home' );
add_filter( 'option_siteurl', '_config_wp_siteurl' );
add_filter( 'tiny_mce_before_init', '_mce_set_direction' );
add_filter( 'teeny_mce_before_init', '_mce_set_direction' );
add_filter( 'pre_kses', 'wp_pre_kses_less_than' );
add_filter( 'sanitize_title', 'sanitize_title_with_dashes', 10, 3 );
add_action( 'check_comment_flood', 'check_comment_flood_db', 10, 3 );
add_filter( 'comment_flood_filter', 'wp_throttle_comment_flood', 10, 3 );
add_filter( 'pre_comment_content', 'wp_rel_nofollow', 15 );
add_filter( 'comment_email', 'antispambot' );
add_filter( 'option_tag_base', '_wp_filter_taxonomy_base' );
add_filter( 'option_category_base', '_wp_filter_taxonomy_base' );
add_filter( 'the_posts', '_close_comments_for_old_posts', 10, 2);
add_filter( 'comments_open', '_close_comments_for_old_post', 10, 2 );
add_filter( 'pings_open', '_close_comments_for_old_post', 10, 2 );
add_filter( 'editable_slug', 'urldecode' );
add_filter( 'editable_slug', 'esc_textarea' );
add_filter( 'nav_menu_meta_box_object', '_wp_nav_menu_meta_box_object' );
add_filter( 'pingback_ping_source_uri', 'pingback_ping_source_uri' );
add_filter( 'xmlrpc_pingback_error', 'xmlrpc_pingback_error' );
add_filter( 'title_save_pre', 'trim' );
add_filter( 'http_request_host_is_external', 'allowed_http_request_hosts', 10, 2 );
// Actions
add_action( 'wp_head', '_wp_render_title_tag', 1 );
add_action( 'wp_head', 'wp_enqueue_scripts', 1 );
add_action( 'wp_head', 'feed_links', 2 );
add_action( 'wp_head', 'feed_links_extra', 3 );
add_action( 'wp_head', 'rsd_link' );
add_action( 'wp_head', 'wlwmanifest_link' );
add_action( 'wp_head', 'adjacent_posts_rel_link_wp_head', 10, 0 );
add_action( 'wp_head', 'locale_stylesheet' );
add_action( 'publish_future_post', 'check_and_publish_future_post', 10, 1 );
add_action( 'wp_head', 'noindex', 1 );
add_action( 'wp_head', 'print_emoji_detection_script', 7 );
add_action( 'wp_head', 'wp_print_styles', 8 );
add_action( 'wp_head', 'wp_print_head_scripts', 9 );
add_action( 'wp_head', 'wp_generator' );
add_action( 'wp_head', 'rel_canonical' );
add_action( 'wp_head', 'wp_shortlink_wp_head', 10, 0 );
add_action( 'wp_head', 'wp_site_icon', 99 );
add_action( 'wp_footer', 'wp_print_footer_scripts', 20 );
add_action( 'template_redirect', 'wp_shortlink_header', 11, 0 );
add_action( 'wp_print_footer_scripts', '_wp_footer_scripts' );
add_action( 'init', 'check_theme_switched', 99 );
add_action( 'after_switch_theme', '_wp_sidebars_changed' );
add_action( 'wp_print_styles', 'print_emoji_styles' );
if ( isset( $_GET['replytocom'] ) )
add_action( 'wp_head', 'wp_no_robots' );
// Login actions
add_action( 'login_head', 'wp_print_head_scripts', 9 );
add_action( 'login_head', 'wp_site_icon', 99 );
add_action( 'login_footer', 'wp_print_footer_scripts', 20 );
add_action( 'login_init', 'send_frame_options_header', 10, 0 );
// Feed Generator Tags
foreach ( array( 'rss2_head', 'commentsrss2_head', 'rss_head', 'rdf_header', 'atom_head', 'comments_atom_head', 'opml_head', 'app_head' ) as $action ) {
add_action( $action, 'the_generator' );
}
// Feed Site Icon
add_action( 'atom_head', 'atom_site_icon' );
add_action( 'rss2_head', 'rss2_site_icon' );
// WP Cron
if ( !defined( 'DOING_CRON' ) )
add_action( 'init', 'wp_cron' );
// 2 Actions 2 Furious
add_action( 'do_feed_rdf', 'do_feed_rdf', 10, 1 );
add_action( 'do_feed_rss', 'do_feed_rss', 10, 1 );
add_action( 'do_feed_rss2', 'do_feed_rss2', 10, 1 );
add_action( 'do_feed_atom', 'do_feed_atom', 10, 1 );
add_action( 'do_pings', 'do_all_pings', 10, 1 );
add_action( 'do_robots', 'do_robots' );
add_action( 'set_comment_cookies', 'wp_set_comment_cookies', 10, 2 );
add_action( 'sanitize_comment_cookies', 'sanitize_comment_cookies' );
add_action( 'admin_print_scripts', 'print_emoji_detection_script' );
add_action( 'admin_print_scripts', 'print_head_scripts', 20 );
add_action( 'admin_print_footer_scripts', '_wp_footer_scripts' );
add_action( 'admin_print_styles', 'print_emoji_styles' );
add_action( 'admin_print_styles', 'print_admin_styles', 20 );
add_action( 'init', 'smilies_init', 5 );
add_action( 'plugins_loaded', 'wp_maybe_load_widgets', 0 );
add_action( 'plugins_loaded', 'wp_maybe_load_embeds', 0 );
add_action( 'shutdown', 'wp_ob_end_flush_all', 1 );
// Create a revision whenever a post is updated.
add_action( 'post_updated', 'wp_save_post_revision', 10, 1 );
add_action( 'publish_post', '_publish_post_hook', 5, 1 );
add_action( 'transition_post_status', '_transition_post_status', 5, 3 );
add_action( 'transition_post_status', '_update_term_count_on_transition_post_status', 10, 3 );
add_action( 'comment_form', 'wp_comment_form_unfiltered_html_nonce' );
add_action( 'wp_scheduled_delete', 'wp_scheduled_delete' );
add_action( 'wp_scheduled_auto_draft_delete', 'wp_delete_auto_drafts' );
add_action( 'admin_init', 'send_frame_options_header', 10, 0 );
add_action( 'importer_scheduled_cleanup', 'wp_delete_attachment' );
add_action( 'upgrader_scheduled_cleanup', 'wp_delete_attachment' );
add_action( 'welcome_panel', 'wp_welcome_panel' );
// Navigation menu actions
add_action( 'delete_post', '_wp_delete_post_menu_item' );
add_action( 'delete_term', '_wp_delete_tax_menu_item', 10, 3 );
add_action( 'transition_post_status', '_wp_auto_add_pages_to_menu', 10, 3 );
// Post Thumbnail CSS class filtering
add_action( 'begin_fetch_post_thumbnail_html', '_wp_post_thumbnail_class_filter_add' );
add_action( 'end_fetch_post_thumbnail_html', '_wp_post_thumbnail_class_filter_remove' );
// Redirect Old Slugs
add_action( 'template_redirect', 'wp_old_slug_redirect' );
add_action( 'post_updated', 'wp_check_for_changed_slugs', 12, 3 );
add_action( 'attachment_updated', 'wp_check_for_changed_slugs', 12, 3 );
// Nonce check for Post Previews
add_action( 'init', '_show_post_preview' );
// Output JS to reset window.name for previews
add_action( 'wp_head', 'wp_post_preview_js', 1 );
// Timezone
add_filter( 'pre_option_gmt_offset','wp_timezone_override_offset' );
// Admin Color Schemes
add_action( 'admin_init', 'register_admin_color_schemes', 1);
add_action( 'admin_color_scheme_picker', 'admin_color_scheme_picker' );
// If the upgrade hasn't run yet, assume link manager is used.
add_filter( 'default_option_link_manager_enabled', '__return_true' );
// This option no longer exists; tell plugins we always support auto-embedding.
add_filter( 'default_option_embed_autourls', '__return_true' );
Force comment pagination on single posts. Previously, the 'page_comments' toggle allowed users to disable comment pagination. This toggle was only superficial, however. Even with 'page_comments' turned on, `comments_template()` loaded all of a post's comments into memory, and passed them to `wp_list_comments()` and `Walker_Comment`, the latter of which produced markup for only the current page of comments. In other words, it was possible to enable 'page_comments', thereby showing only a subset of a post's comments on a given page, but all comments continued to be loaded in the background. This technique scaled poorly. Posts with hundreds or thousands of comments would load slowly, or not at all, even when the 'comments_per_page' setting was set to a reasonable number. Recent changesets have addressed this problem through more efficient tree- walking, better descendant caching, and more selective queries for top-level post comments. The current changeset completes the project by addressing the root issue: that loading a post causes all of its comments to be loaded too. Here's the breakdown: * Comment pagination is now forced. Setting 'page_comments' to false leads to evil things when you have many comments. If you want to avoid pagination, set 'comments_per_page' to something high. * The 'page_comments' setting has been expunged from options-discussion.php, and from places in the codebase where it was referenced. For plugins relying on 'page_comments', we now force the value to `true` with a `pre_option` filter. * `comments_template()` now queries for an appropriately small number of comments. Usually, this means the `comments_per_page` value. * To preserve the current (odd) behavior for comment pagination links, some unholy hacks have been inserted into `comments_template()`. The ugliness is insulated in this function for backward compatibility and to minimize collateral damage. A side-effect is that, for certain settings of 'default_comments_page', up to 2x the value of `comments_per_page` might be fetched at a time. * In support of these changes, a `$format` parameter has been added to `WP_Comment::get_children()`. This param allows you to request a flattened array of comment children, suitable for feeding into `Walker_Comment`. * `WP_Query` loops are now informed about total available comment counts and comment pages by the `WP_Comment_Query` (`found_comments`, `max_num_pages`), instead of by `Walker_Comment`. Aside from radical performance improvements in the case of a post with many comments, this changeset fixes a bug that caused the first page of comments to be partial (`found_comments` % `comments_per_page`), rather than the last, as you'd expect. Props boonebgorges, wonderboymusic. Fixes #8071. Built from https://develop.svn.wordpress.org/trunk@34561 git-svn-id: http://core.svn.wordpress.org/trunk@34525 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-09-25 22:40:25 +02:00
// This option no longer exists; tell plugins we want comment pagination.
add_filter( 'pre_option_page_comments', '__return_true' );
// Default settings for heartbeat
add_filter( 'heartbeat_settings', 'wp_heartbeat_settings' );
// Check if the user is logged out
add_action( 'admin_enqueue_scripts', 'wp_auth_check_load' );
add_filter( 'heartbeat_send', 'wp_auth_check' );
add_filter( 'heartbeat_nopriv_send', 'wp_auth_check' );
// Default authentication filters
add_filter( 'authenticate', 'wp_authenticate_username_password', 20, 3 );
add_filter( 'authenticate', 'wp_authenticate_spam_check', 99 );
add_filter( 'determine_current_user', 'wp_validate_auth_cookie' );
add_filter( 'determine_current_user', 'wp_validate_logged_in_cookie', 20 );
// Split term updates.
add_action( 'admin_init', '_wp_check_for_scheduled_split_terms' );
add_action( 'split_shared_term', '_wp_check_split_default_terms', 10, 4 );
add_action( 'split_shared_term', '_wp_check_split_terms_in_menus', 10, 4 );
add_action( 'split_shared_term', '_wp_check_split_nav_menu_terms', 10, 4 );
add_action( 'wp_split_shared_term_batch', '_wp_batch_split_terms' );
// Email notifications.
add_action( 'comment_post', 'wp_new_comment_notify_moderator' );
add_action( 'comment_post', 'wp_new_comment_notify_postauthor' );
add_action( 'after_password_reset', 'wp_password_change_notification' );
add_action( 'register_new_user', 'wp_send_new_user_notifications' );
add_action( 'edit_user_created_user', 'wp_send_new_user_notifications' );
/**
* Filters formerly mixed into wp-includes
*/
// Theme
add_action( 'wp_loaded', '_custom_header_background_just_in_time' );
add_action( 'plugins_loaded', '_wp_customize_include' );
add_action( 'admin_enqueue_scripts', '_wp_customize_loader_settings' );
add_action( 'delete_attachment', '_delete_attachment_theme_mod' );
// Calendar widget cache
add_action( 'save_post', 'delete_get_calendar_cache' );
add_action( 'delete_post', 'delete_get_calendar_cache' );
add_action( 'update_option_start_of_week', 'delete_get_calendar_cache' );
add_action( 'update_option_gmt_offset', 'delete_get_calendar_cache' );
// Author
add_action( 'transition_post_status', '__clear_multi_author_cache' );
// Post
add_action( 'init', 'create_initial_post_types', 0 ); // highest priority
add_action( 'admin_menu', '_add_post_type_submenus' );
add_action( 'before_delete_post', '_reset_front_page_settings_for_post' );
add_action( 'wp_trash_post', '_reset_front_page_settings_for_post' );
// Post Formats
add_filter( 'request', '_post_format_request' );
add_filter( 'term_link', '_post_format_link', 10, 3 );
add_filter( 'get_post_format', '_post_format_get_term' );
add_filter( 'get_terms', '_post_format_get_terms', 10, 3 );
add_filter( 'wp_get_object_terms', '_post_format_wp_get_object_terms' );
// KSES
add_action( 'init', 'kses_init' );
add_action( 'set_current_user', 'kses_init' );
// Script Loader
add_action( 'wp_default_scripts', 'wp_default_scripts' );
add_filter( 'wp_print_scripts', 'wp_just_in_time_script_localization' );
add_filter( 'print_scripts_array', 'wp_prototype_before_jquery' );
add_action( 'wp_default_styles', 'wp_default_styles' );
add_filter( 'style_loader_src', 'wp_style_loader_src', 10, 2 );
// Taxonomy
add_action( 'init', 'create_initial_taxonomies', 0 ); // highest priority
// Canonical
add_action( 'template_redirect', 'redirect_canonical' );
add_action( 'template_redirect', 'wp_redirect_admin_locations', 1000 );
// Shortcodes
add_filter( 'the_content', 'do_shortcode', 11 ); // AFTER wpautop()
// Media
add_action( 'wp_playlist_scripts', 'wp_playlist_scripts' );
add_action( 'customize_controls_enqueue_scripts', 'wp_plupload_default_settings' );
// Nav menu
add_filter( 'nav_menu_item_id', '_nav_menu_item_id_use_once', 10, 2 );
// Widgets
add_action( 'init', 'wp_widgets_init', 1 );
// Admin Bar
// Don't remove. Wrong way to disable.
add_action( 'template_redirect', '_wp_admin_bar_init', 0 );
add_action( 'admin_init', '_wp_admin_bar_init' );
add_action( 'wp_footer', 'wp_admin_bar_render', 1000 );
add_action( 'in_admin_header', 'wp_admin_bar_render', 0 );
// Former admin filters that can also be hooked on the front end
add_action( 'media_buttons', 'media_buttons' );
add_filter( 'image_send_to_editor', 'image_add_caption', 20, 8 );
add_filter( 'media_send_to_editor', 'image_media_send_to_editor', 10, 3 );
unset( $filter, $action );