(bug 32381) Allow descending order for list=backlinks, list=embeddedin

and list=imageusage

Also avoid some filesorts when using redirect param of that modules
due to fields in order by, which are constant in where

Change-Id: I4b1c4282ab3be9cb93601c57d660520456cf8617

diff --git a/RELEASE-NOTES-1.20 b/RELEASE-NOTES-1.20
index bec1818..a696541 100644 (file)
--- a/RELEASE-NOTES-1.20
+++ b/RELEASE-NOTES-1.20
@@ -173,6 +173,7 @@ upgrade PHP if you have not done so prior to upgrading MediaWiki.
 * (bug 32348) Allow descending order for list=alllinks
 * (bug 31777) Upload unknown error ``fileexists-forbidden''
 * (bug 32382) Allow descending order for list=iwbacklinks
+* (bug 32381) Allow descending order for list=backlinks, list=embeddedin and list=imageusage
 
 === Languages updated in 1.20 ===
 

diff --git a/includes/api/ApiQueryBacklinks.php b/includes/api/ApiQueryBacklinks.php
index 9704b6d..7491bbb 100644 (file)
--- a/includes/api/ApiQueryBacklinks.php
+++ b/includes/api/ApiQueryBacklinks.php
@@ -40,7 +40,7 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
        private $rootTitle;
 
        private $params, $contID, $redirID, $redirect;
-       private $bl_ns, $bl_from, $bl_table, $bl_code, $bl_title, $bl_sort, $bl_fields, $hasNS;
+       private $bl_ns, $bl_from, $bl_table, $bl_code, $bl_title, $bl_fields, $hasNS;
 
        /**
         * Maps ns and title to pageid
@@ -91,14 +91,12 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                $this->hasNS = $moduleName !== 'imageusage';
                if ( $this->hasNS ) {
                        $this->bl_title = $prefix . '_title';
-                       $this->bl_sort = "{$this->bl_ns}, {$this->bl_title}, {$this->bl_from}";
                        $this->bl_fields = array(
                                $this->bl_ns,
                                $this->bl_title
                        );
                } else {
                        $this->bl_title = $prefix . '_to';
-                       $this->bl_sort = "{$this->bl_title}, {$this->bl_from}";
                        $this->bl_fields = array(
                                $this->bl_title
                        );
@@ -144,7 +142,8 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                $this->addWhereFld( 'page_namespace', $this->params['namespace'] );
 
                if ( !is_null( $this->contID ) ) {
-                       $this->addWhere( "{$this->bl_from}>={$this->contID}" );
+                       $op = $this->params['dir'] == 'descending' ? '<' : '>';
+                       $this->addWhere( "{$this->bl_from}$op={$this->contID}" );
                }
 
                if ( $this->params['filterredir'] == 'redirects' ) {
@@ -155,7 +154,8 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                }
 
                $this->addOption( 'LIMIT', $this->params['limit'] + 1 );
-               $this->addOption( 'ORDER BY', $this->bl_from );
+               $sort = ( $this->params['dir'] == 'descending' ? ' DESC' : '' );
+               $this->addOption( 'ORDER BY', $this->bl_from . $sort );
                $this->addOption( 'STRAIGHT_JOIN' );
        }
 
@@ -186,28 +186,35 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
 
                // We can't use LinkBatch here because $this->hasNS may be false
                $titleWhere = array();
+               $allRedirNs = array();
+               $allRedirDBkey = array();
                foreach ( $this->redirTitles as $t ) {
-                       $titleWhere[] = "{$this->bl_title} = " . $db->addQuotes( $t->getDBkey() ) .
-                                       ( $this->hasNS ? " AND {$this->bl_ns} = {$t->getNamespace()}" : '' );
+                       $redirNs = $t->getNamespace();
+                       $redirDBkey = $t->getDBkey();
+                       $titleWhere[] = "{$this->bl_title} = " . $db->addQuotes( $redirDBkey ) .
+                                       ( $this->hasNS ? " AND {$this->bl_ns} = {$redirNs}" : '' );
+                       $allRedirNs[] = $redirNs;
+                       $allRedirDBkey[] = $redirDBkey;
                }
                $this->addWhere( $db->makeList( $titleWhere, LIST_OR ) );
                $this->addWhereFld( 'page_namespace', $this->params['namespace'] );
 
                if ( !is_null( $this->redirID ) ) {
+                       $op = $this->params['dir'] == 'descending' ? '<' : '>';
                        $first = $this->redirTitles[0];
                        $title = $db->addQuotes( $first->getDBkey() );
                        $ns = $first->getNamespace();
                        $from = $this->redirID;
                        if ( $this->hasNS ) {
-                               $this->addWhere( "{$this->bl_ns} > $ns OR " .
+                               $this->addWhere( "{$this->bl_ns} $op $ns OR " .
                                                "({$this->bl_ns} = $ns AND " .
-                                               "({$this->bl_title} > $title OR " .
+                                               "({$this->bl_title} $op $title OR " .
                                                "({$this->bl_title} = $title AND " .
-                                               "{$this->bl_from} >= $from)))" );
+                                               "{$this->bl_from} $op= $from)))" );
                        } else {
-                               $this->addWhere( "{$this->bl_title} > $title OR " .
+                               $this->addWhere( "{$this->bl_title} $op $title OR " .
                                                "({$this->bl_title} = $title AND " .
-                                               "{$this->bl_from} >= $from)" );
+                                               "{$this->bl_from} $op= $from)" );
                        }
                }
                if ( $this->params['filterredir'] == 'redirects' ) {
@@ -217,7 +224,17 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                }
 
                $this->addOption( 'LIMIT', $this->params['limit'] + 1 );
-               $this->addOption( 'ORDER BY', $this->bl_sort );
+               $orderBy = array();
+               $sort = ( $this->params['dir'] == 'descending' ? ' DESC' : '' );
+               // Don't order by namespace/title if it's constant in the WHERE clause
+               if( $this->hasNS && count( array_unique( $allRedirNs ) ) != 1 ) {
+                       $orderBy[] = $this->bl_ns . $sort;
+               }
+               if( count( array_unique( $allRedirDBkey ) ) != 1 ) {
+                       $orderBy[] = $this->bl_title . $sort;
+               }
+               $orderBy[] = $this->bl_from . $sort;
+               $this->addOption( 'ORDER BY', $orderBy );
                $this->addOption( 'USE INDEX', array( 'page' => 'PRIMARY' ) );
        }
 
@@ -438,6 +455,13 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                                ApiBase::PARAM_ISMULTI => true,
                                ApiBase::PARAM_TYPE => 'namespace'
                        ),
+                       'dir' => array(\r
+                               ApiBase::PARAM_DFLT => 'ascending',\r
+                               ApiBase::PARAM_TYPE => array(\r
+                                       'ascending',\r
+                                       'descending'\r
+                               )\r
+                       ),
                        'filterredir' => array(
                                ApiBase::PARAM_DFLT => 'all',
                                ApiBase::PARAM_TYPE => array(
@@ -467,6 +491,7 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                        'pageid' => "Pageid to search. Cannot be used together with {$this->bl_code}title",
                        'continue' => 'When more results are available, use this to continue',
                        'namespace' => 'The namespace to enumerate',
+                       'dir' => 'The direction in which to list',
                );
                if ( $this->getModuleName() != 'embeddedin' ) {
                        return array_merge( $retval, array(