Changeset 25632

Timestamp:

09/27/2013 05:33:36 PM (11 years ago)

Author:

nacin

Message:

Order search results by relevance, rather than by date.

The ordering logic is as follows:

• Full sentence matches in post titles.
• All search terms in post titles.
• Any search terms in post titles.
• Full sentence matches in post content.

Each section and any remaining posts are then sorted by date.

Introduces some filters:

• wp_search_stopwords, to filter stop words ignored in WHERE.
• posts_search_orderby, to filter the ORDER BY when ordering search results.

props azaozz, wonderboymusic.
fixes #7394.

Location:

trunk/src/wp-includes

Files:

• deprecated.php (modified) (1 diff)
• functions.php (modified) (1 diff)
• query.php (modified) (5 diffs)

trunk/src/wp-includes/deprecated.php

@@ -3318 +3318 @@
 
 /**
+ * Formerly used internally to tidy up the search terms.
+ *
+ * @access private
+ * @since 2.9.0
+ * @deprecated 3.7.0
+ */
+function _search_terms_tidy( $t ) {
+    _deprecated_function( __FUNCTION__, '3.5', '' );
+    return trim( $t, "\"'\n\r " );
+}
+
+/**
  * Check if the installed version of GD supports particular image type
  *

trunk/src/wp-includes/functions.php

@@ -3704 +3704 @@
 
 /**
- * Used internally to tidy up the search terms.
- *
- * @access private
- * @since 2.9.0
- *
- * @param string $t
- * @return string
- */
-function _search_terms_tidy($t) {
-    return trim($t, "\"'\n\r ");
-}
-
-/**
  * Returns true.
  *

trunk/src/wp-includes/query.php

@@ -1289 +1289 @@
      */
      var $thumbnails_cached = false;
+
+    /**
+     * Cached list of search stopwords.
+     *
+     * @since 3.7.0
+     * @var array
+     */
+    private $stopwords;
 
     /**
@@ -1471 +1479 @@
         if ( '' !== $qv['menu_order'] ) $qv['menu_order'] = absint($qv['menu_order']);
 
+        // Fairly insane upper bound for search string lengths.
+        if ( ! empty( $qv['s'] ) && strlen( $qv['s'] ) > 1600 )
+            $qv['s'] = '';
+
         // Compat. Map subpost to attachment.
         if ( '' != $qv['subpost'] )
@@ -1896 +1908 @@
 
     /**
+     * Generate SQL for the WHERE clause based on passed search terms.
+     *
+     * @since 3.7.0
+     *
+     * @global type $wpdb
+     * @param array $q Query variables.
+     */
+    protected function parse_search( &$q ) {
+        global $wpdb;
+
+        $search = '';
+
+        // added slashes screw with quote grouping when done early, so done later
+        $q['s'] = stripslashes( $q['s'] );
+        if ( empty( $_GET['s'] ) && $this->is_main_query() )
+            $q['s'] = urldecode( $q['s'] );
+        // there are no line breaks in <input /> fields
+        $q['s'] = str_replace( array( "\r", "\n" ), '', $q['s'] );
+        $q['search_terms_count'] = 1;
+        if ( ! empty( $q['sentence'] ) ) {
+            $q['search_terms'] = array( $q['s'] );
+        } else {
+            if ( preg_match_all( '/".*?("|$)|((?<=[\t ",+])|^)[^\t ",+]+/', $q['s'], $matches ) ) {
+                $q['search_terms_count'] = count( $matches[0] );
+                $q['search_terms'] = $this->parse_search_terms( $matches[0] );
+                // if the search string has only short terms or stopwords, or is 10+ terms long, match it as sentence
+                if ( empty( $q['search_terms'] ) || count( $q['search_terms'] ) > 9 )
+                    $q['search_terms'] = array( $q['s'] );
+            } else {
+                $q['search_terms'] = array( $q['s'] );
+            }
+        }
+
+        $n = ! empty( $q['exact'] ) ? '' : '%';
+        $searchand = '';
+        $q['search_orderby_title'] = array();
+        foreach ( $q['search_terms'] as $term ) {
+            $term = like_escape( esc_sql( $term ) );
+            if ( $n )
+                $q['search_orderby_title'][] = "$wpdb->posts.post_title LIKE '%$term%'";
+
+            $search .= "{$searchand}(($wpdb->posts.post_title LIKE '{$n}{$term}{$n}') OR ($wpdb->posts.post_content LIKE '{$n}{$term}{$n}'))";
+            $searchand = ' AND ';
+        }
+
+        if ( ! empty( $search ) ) {
+            $search = " AND ({$search}) ";
+            if ( ! is_user_logged_in() )
+                $search .= " AND ($wpdb->posts.post_password = '') ";
+        }
+
+        /**
+         * Filter the search SQL that is used in the WHERE clause of WP_Query.
+         *
+         * @since 3.0.0
+         *
+         * @param string   $search Search SQL for WHERE clause.
+         * @param WP_Query $this   The current WP_Query object.
+         */
+        return apply_filters_ref_array( 'posts_search', array( $search, &$this ) );
+    }
+
+    /**
+     * Check if the terms are suitable for searching.
+     *
+     * Uses an array of stopwords (terms) that are excluded from the separate
+     * term matching when searching for posts. The list of English stopwords is
+     * the approximate search engines list, and is translatable.
+     *
+     * @since 3.7.0
+     *
+     * @param array Terms to check.
+     * @return array Terms that are not stopwords.
+     */
+    protected function parse_search_terms( $terms ) {
+        $strtolower = function_exists( 'mb_strtolower' ) ? 'mb_strtolower' : 'strtolower';
+        $checked = array();
+
+        $stopwords = $this->get_search_stopwords();
+
+        foreach ( $terms as $term ) {
+            // keep before/after spaces when term is for exact match
+            if ( preg_match( '/^".+"$/', $term ) )
+                $term = trim( $term, "\"'" );
+            else
+                $term = trim( $term, "\"' " );
+
+            // \p{L} matches a single letter that is not a Chinese, Japanese, etc. char
+            if ( ! $term || preg_match( '/^\p{L}$/u', $term ) )
+                continue;
+
+            if ( in_array( call_user_func( $strtolower, $term ), $stopwords, true ) )
+                continue;
+
+            $checked[] = $term;
+        }
+
+        return $checked;
+    }
+
+    /**
+     * Retrieve stopwords used when parsing search terms.
+     *
+     * @since 3.7.0
+     *
+     * @return array Stopwords.
+     */
+    protected function get_search_stopwords() {
+        if ( isset( $this->stopwords ) )
+            return $this->stopwords;
+
+        /* translators: This is a comma-separated list of very common words that should be excluded from a search,
+         * like a, an, and the. These are usually called "stopwords". You should not simply translate these individual
+         * words into your language. Instead, look for and provide commonly accepted stopwords in your language.
+         */
+        $words = explode( ',', _x( 'about,an,are,as,at,be,by,com,for,from,how,in,is,it,of,on,or,that,the,this,to,was,what,when,where,who,will,with,www',
+            'Comma-separated list of search stopwords in your language' ) );
+
+        foreach( $words as $word ) {
+            $word = trim( $word, "\r\n\t " );
+            if ( $word )
+                $stopwords[] = $word;
+        }
+
+        /**
+         * Filter stopwords used when parsing search terms.
+         *
+         * @since 3.7.0
+         *
+         * @param array $stopwords Stopwords.
+         */
+        $this->stopwords = apply_filters( 'wp_search_stopwords', $stopwords );
+        return $this->stopwords;
+    }
+
+    /**
+     * Generate SQL for the ORDER BY condition based on passed search terms.
+     *
+     * @global wpdb $wpdb
+     * @param array $q Query variables.
+     * @return string ORDER BY clause.
+     */
+    protected function parse_search_order( &$q ) {
+        global $wpdb;
+
+        $search_orderby = '';
+
+        if ( $q['search_terms_count'] > 1 ) {
+            $num_terms = count( $q['search_orderby_title'] );
+            $search_orderby_s = like_escape( esc_sql( $q['s'] ) );
+
+            $search_orderby = '(CASE ';
+            // sentence match in 'post_title'
+            $search_orderby .= "WHEN $wpdb->posts.post_title LIKE '%{$search_orderby_s}%' THEN 1 ";
+
+            // sanity limit, sort as sentence when more than 6 terms
+            // (few searches are longer than 6 terms and most titles are not)
+            if ( $num_terms < 7 ) {
+                // all words in title
+                $search_orderby .= 'WHEN ' . implode( ' AND ', $q['search_orderby_title'] ) . ' THEN 2 ';
+                // any word in title, not needed when $num_terms == 1
+                if ( $num_terms > 1 )
+                    $search_orderby .= 'WHEN ' . implode( ' OR ', $q['search_orderby_title'] ) . ' THEN 3 ';
+            }
+
+            // sentence match in 'post_content'
+            $search_orderby .= "WHEN $wpdb->posts.post_content LIKE '%{$search_orderby_s}%' THEN 4 ";
+            $search_orderby .= 'ELSE 5 END)';
+        } else {
+            // single word or sentence search
+            $search_orderby = reset( $q['search_orderby_title'] ) . ' DESC';
+        }
+
+        return $search_orderby;
+    }
+
+    /**
      * Sets the 404 property and saves whether query is feed.
      *
@@ -2236 +2425 @@
         }
 
-        // If a search pattern is specified, load the posts that match
-        if ( !empty($q['s']) ) {
-            // added slashes screw with quote grouping when done early, so done later
-            $q['s'] = stripslashes($q['s']);
-            if ( empty( $_GET['s'] ) && $this->is_main_query() )
-                $q['s'] = urldecode($q['s']);
-            if ( !empty($q['sentence']) ) {
-                $q['search_terms'] = array($q['s']);
-            } else {
-                preg_match_all('/".*?("|$)|((?<=[\r\n\t ",+])|^)[^\r\n\t ",+]+/', $q['s'], $matches);
-                $q['search_terms'] = array_map('_search_terms_tidy', $matches[0]);
-            }
-            $n = !empty($q['exact']) ? '' : '%';
-            $searchand = '';
-            foreach( (array) $q['search_terms'] as $term ) {
-                $term = esc_sql( like_escape( $term ) );
-                $search .= "{$searchand}(($wpdb->posts.post_title LIKE '{$n}{$term}{$n}') OR ($wpdb->posts.post_content LIKE '{$n}{$term}{$n}'))";
-                $searchand = ' AND ';
-            }
-
-            if ( !empty($search) ) {
-                $search = " AND ({$search}) ";
-                if ( !is_user_logged_in() )
-                    $search .= " AND ($wpdb->posts.post_password = '') ";
-            }
-        }
-
-        // Allow plugins to contextually add/remove/modify the search section of the database query
-        $search = apply_filters_ref_array('posts_search', array( $search, &$this ) );
+        // If a search pattern is specified, load the posts that match.
+        if ( ! empty( $q['s'] ) )
+            $search = $this->parse_search( $q );
 
         // Taxonomies
@@ -2462 +2625 @@
         }
 
+        // Order search results by relevance only when another "orderby" is not specified in the query.
+        if ( ! empty( $q['s'] ) ) {
+            $search_orderby = '';
+            if ( ! empty( $q['search_orderby_title'] ) && empty( $q['orderby'] ) )
+                $search_orderby = $this->parse_search_order( $q );
+
+            /**
+             * Filter the ORDER BY used when ordering search results.
+             *
+             * @since 3.7.0
+             *
+             * @param string   $search_orderby The ORDER BY clause.
+             * @param WP_Query $this           The current WP_Query instance.
+             */
+            $search_orderby = apply_filters( 'posts_search_orderby', $search_orderby, $this );
+            if ( $search_orderby )
+                $orderby = $orderby ? $search_orderby . ', ' . $orderby : $search_orderby;
+        }
+
         if ( is_array( $post_type ) && count( $post_type ) > 1 ) {
             $post_type_cap = 'multiple_post_type';