From d70050053ad359102384a38f332db0e3ea59f991 Mon Sep 17 00:00:00 2001
From: Roan Kattouw <catrope@users.mediawiki.org>
Date: Wed, 14 Jan 2009 17:04:46 +0000
Subject: [PATCH] API: (bug 16844) Added clcategories parameter to
 prop=category to make checking whether a certain page is in a certain
 category more efficient

---
 RELEASE-NOTES                       |  1 +
 includes/api/ApiQueryCategories.php | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/RELEASE-NOTES b/RELEASE-NOTES
index 2e0609c519..dceef20503 100644
--- a/RELEASE-NOTES
+++ b/RELEASE-NOTES
@@ -49,6 +49,7 @@ it from source control: http://www.mediawiki.org/wiki/Download_from_SVN
   incorrectly
 * (bug 16858) Revamped list=deletedrevs to make listing deleted contributions
   and listing all deleted pages possible
+* (bug 16844) Added clcategories parameter to prop=categories
 
 === Languages updated in 1.15 ===
 
diff --git a/includes/api/ApiQueryCategories.php b/includes/api/ApiQueryCategories.php
index cbff86bd0f..badca7ccc7 100644
--- a/includes/api/ApiQueryCategories.php
+++ b/includes/api/ApiQueryCategories.php
@@ -81,6 +81,19 @@ class ApiQueryCategories extends ApiQueryGeneratorBase {
 
 		$this->addTables('categorylinks');
 		$this->addWhereFld('cl_from', array_keys($this->getPageSet()->getGoodTitles()));
+		if(!is_null($params['categories']))
+		{
+			$cats = array();
+			foreach($params['categories'] as $cat)
+			{
+				$title = Title::newFromText($cat);
+				if($title->getNamespace() != NS_CATEGORY)
+					$this->setWarning("``$cat'' is not a category");
+				else
+					$cats[] = $title->getDBkey();
+			}
+			$this->addWhereFld('cl_to', $cats);
+		}
 		if(!is_null($params['continue'])) {
 			$cont = explode('|', $params['continue']);
 			if(count($cont) != 2)
@@ -112,6 +125,7 @@ class ApiQueryCategories extends ApiQueryGeneratorBase {
 				$this->addWhere(array('pp_propname IS NULL'));
 		}
 
+		$this->addOption('USE INDEX', array('categorylinks' => 'cl_from'));
 		# Don't order by cl_from if it's constant in the WHERE clause
 		if(count($this->getPageSet()->getGoodTitles()) == 1)
 			$this->addOption('ORDER BY', 'cl_to');
@@ -202,6 +216,9 @@ class ApiQueryCategories extends ApiQueryGeneratorBase {
 				ApiBase :: PARAM_MAX2 => ApiBase :: LIMIT_BIG2
 			),
 			'continue' => null,
+			'categories' => array(
+				ApiBase :: PARAM_ISMULTI => true,
+			),
 		);
 	}
 
@@ -211,6 +228,7 @@ class ApiQueryCategories extends ApiQueryGeneratorBase {
 			'limit' => 'How many categories to return',
 			'show' => 'Which kind of categories to show',
 			'continue' => 'When more results are available, use this to continue',
+			'categories' => 'Only list these categories. Useful for checking whether a certain page is in a certain category',
 		);
 	}
 
-- 
2.20.1