From 59e00d43a5353d5a59f94911dd8bfeb79d066470 Mon Sep 17 00:00:00 2001
From: Pascal Birchler <swissspidy@git.wordpress.org>
Date: Fri, 14 Apr 2017 08:39:46 +0000
Subject: [PATCH] Media: Add filters to allow overriding slow media queries.

There are a couple of queries that do a full table scan of attachment posts to support features of the media library. Pending a more complete solution, allow overriding these queries via filters.

Props sboisvert, jnylen0.
See #31071.

Merges [40382] and [40421] to the 4.7 branch.


git-svn-id: https://develop.svn.wordpress.org/branches/4.7@40425 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/media.php | 101 +++++++++++++++++++++++++++++---------
 1 file changed, 78 insertions(+), 23 deletions(-)

diff --git a/src/wp-includes/media.php b/src/wp-includes/media.php
index 3411b84c80..3d2f850df9 100644
--- a/src/wp-includes/media.php
+++ b/src/wp-includes/media.php
@@ -3319,26 +3319,81 @@ function wp_enqueue_media( $args = array() ) {
 		}
 	}
 
-	$has_audio = $wpdb->get_var( "
-		SELECT ID
-		FROM $wpdb->posts
-		WHERE post_type = 'attachment'
-		AND post_mime_type LIKE 'audio%'
-		LIMIT 1
-	" );
-	$has_video = $wpdb->get_var( "
-		SELECT ID
-		FROM $wpdb->posts
-		WHERE post_type = 'attachment'
-		AND post_mime_type LIKE 'video%'
-		LIMIT 1
-	" );
-	$months = $wpdb->get_results( $wpdb->prepare( "
-		SELECT DISTINCT YEAR( post_date ) AS year, MONTH( post_date ) AS month
-		FROM $wpdb->posts
-		WHERE post_type = %s
-		ORDER BY post_date DESC
-	", 'attachment' ) );
+	/**
+	 * Allows showing or hiding the "Create Audio Playlist" button in the media library.
+	 *
+	 * By default (if this filter returns `null`), a query will be run to
+	 * determine whether the media library contains any audio items.  This
+	 * query is expensive for large media libraries, so it may be desirable for
+	 * sites to override this behavior.
+	 *
+	 * @since 4.7.4
+	 *
+	 * @link https://core.trac.wordpress.org/ticket/31071
+	 *
+	 * @param bool|null Whether to show the button, or `null` for default behavior.
+	 */
+	$show_audio_playlist = apply_filters( 'media_library_show_audio_playlist', null );
+	if ( null === $show_audio_playlist ) {
+		$show_audio_playlist = $wpdb->get_var( "
+			SELECT ID
+			FROM $wpdb->posts
+			WHERE post_type = 'attachment'
+			AND post_mime_type LIKE 'audio%'
+			LIMIT 1
+		" );
+	}
+
+	/**
+	 * Allows showing or hiding the "Create Video Playlist" button in the media library.
+	 *
+	 * By default (if this filter returns `null`), a query will be run to
+	 * determine whether the media library contains any video items.  This
+	 * query is expensive for large media libraries, so it may be desirable for
+	 * sites to override this behavior.
+	 *
+	 * @since 4.7.4
+	 *
+	 * @link https://core.trac.wordpress.org/ticket/31071
+	 *
+	 * @param bool|null Whether to show the button, or `null` for default behavior.
+	 */
+	$show_video_playlist = apply_filters( 'media_library_show_video_playlist', null );
+	if ( null === $show_video_playlist ) {
+		$show_video_playlist = $wpdb->get_var( "
+			SELECT ID
+			FROM $wpdb->posts
+			WHERE post_type = 'attachment'
+			AND post_mime_type LIKE 'video%'
+			LIMIT 1
+		" );
+	}
+
+	/**
+	 * Allows overriding the list of months displayed in the media library.
+	 *
+	 * By default (if this filter does not return an array), a query will be
+	 * run to determine the months that have media items.  This query can be
+	 * expensive for large media libraries, so it may be desirable for sites to
+	 * override this behavior.
+	 *
+	 * @since 4.7.4
+	 *
+	 * @link https://core.trac.wordpress.org/ticket/31071
+	 *
+	 * @param array|null An array of objects with `month` and `year`
+	 *                   properties, or `null` (or any other non-array value)
+	 *                   for default behavior.
+	 */
+	$months = apply_filters( 'media_library_months_with_files', null );
+	if ( ! is_array( $months ) ) {
+		$months = $wpdb->get_results( $wpdb->prepare( "
+			SELECT DISTINCT YEAR( post_date ) AS year, MONTH( post_date ) AS month
+			FROM $wpdb->posts
+			WHERE post_type = %s
+			ORDER BY post_date DESC
+		", 'attachment' ) );
+	}
 	foreach ( $months as $month_year ) {
 		$month_year->text = sprintf( __( '%1$s %2$d' ), $wp_locale->get_month( $month_year->month ), $month_year->year );
 	}
@@ -3357,14 +3412,14 @@ function wp_enqueue_media( $args = array() ) {
 		),
 		'defaultProps' => $props,
 		'attachmentCounts' => array(
-			'audio' => ( $has_audio ) ? 1 : 0,
-			'video' => ( $has_video ) ? 1 : 0
+			'audio' => ( $show_audio_playlist ) ? 1 : 0,
+			'video' => ( $show_video_playlist ) ? 1 : 0,
 		),
 		'embedExts'    => $exts,
 		'embedMimes'   => $ext_mimes,
 		'contentWidth' => $content_width,
 		'months'       => $months,
-		'mediaTrash'   => MEDIA_TRASH ? 1 : 0
+		'mediaTrash'   => MEDIA_TRASH ? 1 : 0,
 	);
 
 	$post = null;