API: Rewriting ApiQueryBacklinks big time. Implemented blredirect and cleaned up...
authorRoan Kattouw <catrope@users.mediawiki.org>
Mon, 25 Feb 2008 14:32:57 +0000 (14:32 +0000)
committerRoan Kattouw <catrope@users.mediawiki.org>
Mon, 25 Feb 2008 14:32:57 +0000 (14:32 +0000)
includes/api/ApiQueryBacklinks.php

index 924725c..f5d11d7 100644 (file)
@@ -38,7 +38,7 @@ if (!defined('MEDIAWIKI')) {
  */
 class ApiQueryBacklinks extends ApiQueryGeneratorBase {
 
-       private $params, $rootTitle, $contRedirs, $contLevel, $contTitle, $contID;
+       private $params, $rootTitle, $contRedirs, $contLevel, $contTitle, $contID, $redirID;
 
        // output element name, database column field prefix, database table 
        private $backlinksSettings = array (
@@ -66,10 +66,7 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                parent :: __construct($query, $moduleName, $code);
                $this->bl_ns = $prefix . '_namespace';
                $this->bl_from = $prefix . '_from';
-               $this->bl_tables = array (
-                       $linktbl,
-                       'page'
-               );
+               $this->bl_table = $linktbl;
                $this->bl_code = $code;
 
                $this->hasNS = $moduleName !== 'imageusage';
@@ -96,115 +93,173 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
        public function executeGenerator($resultPageSet) {
                $this->run($resultPageSet);
        }
-
-       private function run($resultPageSet = null) {
-               $this->params = $this->extractRequestParams();
-               
-               $redirect = $this->params['redirect'];
-               if ($redirect)
-                       $this->dieDebug('Redirect has not been implemented', 'notimplemented');
-
-               $this->processContinue();
-
-               $this->addFields($this->bl_fields);
-               if (is_null($resultPageSet))
-                       $this->addFields(array (
-                               'page_id',
-                               'page_namespace',
-                               'page_title'
-                       ));
+       
+       private function prepareFirstQuery($resultPageSet = null) {
+               /* SELECT page_id, page_title, page_namespace, page_is_redirect
+                * FROM pagelinks JOIN page ON pl_from=page_id
+                * WHERE pl_title='Foo' AND pl_namespace=0
+                * LIMIT 11 ORDER BY pl_from
+                */
+               $db = $this->getDb();
+               list($tblpage, $tbllinks) = $db->tableNamesN('page', $this->bl_table);
+               $this->addTables("$tbllinks JOIN $tblpage ON {$this->bl_from}=page_id");
+               if(is_null($resultPageSet))
+                       $this->addFields(array('page_id', 'page_title', 'page_namespace', 'page_is_redirect'));
                else
-                       $this->addFields($resultPageSet->getPageTableFields()); // will include page_id
-
-               $this->addTables($this->bl_tables);
-               $this->addWhere($this->bl_from . '=page_id');
-
-               if ($this->hasNS)
+                       $this->addFields($resultPageSet->getPageTableFields());
+               $this->addWhereFld($this->bl_title, $this->rootTitle->getDbKey());
+               if($this->hasNS)
                        $this->addWhereFld($this->bl_ns, $this->rootTitle->getNamespace());
-               $this->addWhereFld($this->bl_title, $this->rootTitle->getDBkey());
                $this->addWhereFld('page_namespace', $this->params['namespace']);
-
+               if(!is_null($this->contID))
+                       $this->addWhere("page_id>={$this->contID}");
                if($this->params['filterredir'] == 'redirects')
                        $this->addWhereFld('page_is_redirect', 1);
                if($this->params['filterredir'] == 'nonredirects')
                        $this->addWhereFld('page_is_redirect', 0);
-
-               $limit = $this->params['limit'];
-               $this->addOption('LIMIT', $limit +1);
+               $this->addOption('LIMIT', $this->params['limit'] + 1);
+               $this->addOption('ORDER BY', $this->bl_from);
+       }
+       
+       private function prepareSecondQuery($resultPageSet = null) {
+               /* SELECT page_id, page_title, page_namespace, page_is_redirect, pl_title, pl_namespace
+                * FROM pagelinks JOIN page ON pl_from=page_id
+                * WHERE (pl_title='Foo' AND pl_namespace=0) OR (pl_title='Bar' AND pl_namespace=1)
+                * LIMIT 11 ORDER BY pl_namespace, pl_title, pl_from
+                */
+               $db = $this->getDb();
+               list($tblpage, $tbllinks) = $db->tableNamesN('page', $this->bl_table);
+               $this->addTables("$tbllinks JOIN $tblpage ON {$this->bl_from}=page_id");
+               if(is_null($resultPageSet))
+                       $this->addFields(array('page_id', 'page_title', 'page_namespace', 'page_is_redirect'));
+               else
+                       $this->addFields($resultPageSet->getPageTableFields());
+               $this->addFields($this->bl_title);
+               if($this->hasNS)
+                       $this->addFields($this->bl_ns);
+               $titleWhere = '';
+               foreach($this->redirTitles as $t)
+                       $titleWhere .= ($titleWhere != '' ? " OR " : '') . 
+                                       "({$this->bl_title} = '{$t->getDBKey()}'" .
+                                       ($this->hasNS ? " AND {$this->bl_ns} = '{$t->getNamespace()}'" : "") .
+                                       ")";
+               $this->addWhere($titleWhere);
+               $this->addWhereFld('page_namespace', $this->params['namespace']);
+               if(!is_null($this->redirID))
+                       $this->addWhere("page_id>={$this->redirID}");
+               if($this->params['filterredir'] == 'redirects')
+                       $this->addWhereFld('page_is_redirect', 1);
+               if($this->params['filterredir'] == 'nonredirects')
+                       $this->addWhereFld('page_is_redirect', 0);
+               $this->addOption('LIMIT', $this->params['limit'] + 1);
                $this->addOption('ORDER BY', $this->bl_sort);
+       }
 
-               $db = $this->getDB();
-               if (!is_null($this->params['continue'])) {
-                       $plfrm = intval($this->contID);
-                       if ($this->contLevel == 0) {
-                               // For the first level, there is only one target title, so no need for complex filtering
-                               $this->addWhere($this->bl_from . '>=' . $plfrm);
-                       } else {
-                               $ns = $this->contTitle->getNamespace();
-                               $t = $db->addQuotes($this->contTitle->getDBkey());
-                               $whereWithoutNS = "{$this->bl_title}>$t OR ({$this->bl_title}=$t AND {$this->bl_from}>=$plfrm))";
-
-                               if ($this->hasNS)
-                                       $this->addWhere("{$this->bl_ns}>$ns OR ({$this->bl_ns}=$ns AND ($whereWithoutNS)");
-                               else
-                                       $this->addWhere($whereWithoutNS);
-                       }
+       private function run($resultPageSet = null) {
+               $this->params = $this->extractRequestParams(false);
+               $userMax = ( $this->params['redirect'] ? ApiBase::LIMIT_BIG1/2 : ApiBase::LIMIT_BIG1 );
+               $botMax  = ( $this->params['redirect'] ? ApiBase::LIMIT_BIG2/2 : ApiBase::LIMIT_BIG2 );
+               if( $this->params['limit'] == 'max' ) {
+                       $this->params['limit'] = $this->getMain()->canApiHighLimits() ? $botMax : $userMax;
+                       $this->getResult()->addValue( 'limits', $this->getModuleName(), $this->params['limit'] );
                }
 
+               $this->processContinue();
+               $this->prepareFirstQuery($resultPageSet);
+
+               $db = $this->getDB();
                $res = $this->select(__METHOD__);
 
                $count = 0;
-               $data = array ();
+               $this->data = array ();
+               $this->continueStr = null;
+               $this->redirTitles = array();
                while ($row = $db->fetchObject($res)) {
-                       if (++ $count > $limit) {
+                       if (++ $count > $this->params['limit']) {
                                // We've reached the one extra which shows that there are additional pages to be had. Stop here...
-                               if ($redirect) {
-                                       $ns = $row-> { $this->bl_ns };
-                                       $t = $row-> { $this->bl_title };
-                                       $continue = $this->getContinueRedirStr(false, 0, $ns, $t, $row->page_id);
-                               } else
-                                       $continue = $this->getContinueStr($row->page_id);
-                               // TODO: Security issue - if the user has no right to view next title, it will still be shown
-                               $this->setContinueEnumParameter('continue', $continue);
+                               // Continue string preserved in case the redirect query doesn't pass the limit
+                               $this->continueStr = $this->getContinueStr($row->page_id);
                                break;
                        }
 
-                       if (is_null($resultPageSet)) {
-                               $vals = $this->extractRowInfo($row);
-                               if ($vals)
-                                       $data[] = $vals;
-                       } else {
+                       if (is_null($resultPageSet))
+                               $this->extractRowInfo($row);
+                       else
                                $resultPageSet->processDbRow($row);
+               }       
+               $db->freeResult($res);
+               
+               if($this->params['redirect'] && !empty($this->redirTitles))
+               {
+                       $this->resetQueryParams();
+                       $this->prepareSecondQuery($resultPageSet);
+                       $res = $this->select(__METHOD__);
+                       $count = 0;
+                       while($row = $db->fetchObject($res))
+                       {
+                               if(++$count > $this->params['limit'])
+                               {
+                                       // We've reached the one extra which shows that there are additional pages to be had. Stop here...
+                                       // We need to keep the parent page of this redir in
+                                       if($this->hasNS)
+                                               $contTitle = Title::makeTitle($row->{$this->bl_ns}, $row->{$this->bl_title});
+                                       else
+                                               $contTitle = Title::makeTitle(NS_IMAGE, $row->{$this->bl_title});
+                                       $this->continueStr = $this->getContinueRedirStr($contTitle->getArticleID(), $row->page_id);
+                                       break;
+                               }
+                               
+                               if(is_null($resultPageSet))
+                                       $this->extractRedirRowInfo($row);
+                               else
+                                       $resultPageSet->processDbRow($row);
                        }
+                       $db->freeResult($res);
                }
-               $db->freeResult($res);
+               if(!is_null($this->continueStr))
+                       $this->setContinueEnumParameter('continue', $this->continueStr);
 
                if (is_null($resultPageSet)) {
+                       $resultData = array();
+                       foreach($this->data as $ns => $a)
+                               foreach($a as $title => $arr)
+                                       $resultData[$arr['pageid']] = $arr;
                        $result = $this->getResult();
-                       $result->setIndexedTagName($data, $this->bl_code);
-                       $result->addValue('query', $this->getModuleName(), $data);
+                       $result->setIndexedTagName($resultData, $this->bl_code);
+                       $result->addValue('query', $this->getModuleName(), $resultData);
                }
        }
 
        private function extractRowInfo($row) {
-
-               $vals = array();
-               $vals['pageid'] = intval($row->page_id);
-               ApiQueryBase :: addTitleInfo($vals, Title :: makeTitle($row->page_namespace, $row->page_title));
-
-               return $vals;
+               if(!isset($this->data[$row->page_namespace][$row->page_title])) {
+                       $this->data[$row->page_namespace][$row->page_title]['pageid'] = $row->page_id;
+                       ApiQueryBase::addTitleInfo($this->data[$row->page_namespace][$row->page_title], Title::makeTitle($row->page_namespace, $row->page_title));
+                       if($row->page_is_redirect)
+                       {
+                               $this->data[$row->page_namespace][$row->page_title]['redirect'] = '';
+                               $this->redirTitles[] = Title::makeTitle($row->page_namespace, $row->page_title);
+                       }
+               }
+       }
+       
+       private function extractRedirRowInfo($row)
+       {
+               $a['pageid'] = $row->page_id;
+               ApiQueryBase::addTitleInfo($a, Title::makeTitle($row->page_namespace, $row->page_title));
+               if($row->page_is_redirect)
+                       $a['redirect'] = '';
+               $ns = $this->hasNS ? $row->{$this->bl_ns} : NS_IMAGE;
+               $this->data[$ns][$row->{$this->bl_title}]['redirlinks'][] = $a;
+               $this->getResult()->setIndexedTagName($this->data[$ns][$row->{$this->bl_title}]['redirlinks'], $this->bl_code); 
        }
 
        protected function processContinue() {
                $pageSet = $this->getPageSet();
                $count = $pageSet->getTitleCount();
                
-               if (!is_null($this->params['continue'])) {
+               if (!is_null($this->params['continue']))
                        $this->parseContinueParam();
-
-                       // Skip all completed links
-
-               } else {
+               else {
                        $title = $this->params['title'];
                        if (!is_null($title)) {
                                $this->rootTitle = Title :: newFromText($title);
@@ -216,88 +271,38 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                        }
                }
 
-               // only image titles are allowed for the root 
+               // only image titles are allowed for the root in imageinfo mode
                if (!$this->hasNS && $this->rootTitle->getNamespace() !== NS_IMAGE)
                        $this->dieUsage("The title for {$this->getModuleName()} query must be an image", 'bad_image_title');
        }
 
        protected function parseContinueParam() {
                $continueList = explode('|', $this->params['continue']);
-               if ($this->params['redirect']) {
-                       //
-                       // expected redirect-mode parameter:
-                       // ns|db_key|step|level|ns|db_key|id
-                       // ns+db_key -- the root title
-                       // step = 1 or 2 - which step to continue from - 1-titles, 2-redirects
-                       // level -- how many levels to follow before starting enumerating.
-                       // if level > 0 -- ns+title to continue from, otherwise skip these 
-                       // id = last page_id to continue from
-                       //
-                       if (count($continueList) > 4) {
-                               $rootNs = intval($continueList[0]);
-                               if (($rootNs !== 0 || $continueList[0] === '0') && !empty ($continueList[1])) {
-                                       $this->rootTitle = Title :: makeTitleSafe($rootNs, $continueList[1]);
-                                       if ($this->rootTitle) {
-
-                                               $step = intval($continueList[2]);
-                                               if ($step === 1 || $step === 2) {
-                                                       $this->contRedirs = ($step === 2);
-
-                                                       $level = intval($continueList[3]);
-                                                       if ($level !== 0 || $continueList[3] === '0') {
-                                                               $this->contLevel = $level;
-
-                                                               if ($level === 0) {
-                                                                       if (count($continueList) === 5) {
-                                                                               $contID = intval($continueList[4]);
-                                                                               if ($contID !== 0 || $continueList[4] === '0') {
-                                                                                       $this->contID = $contID;
-                                                                                       return; // done
-                                                                               }
-                                                                       }
-                                                               } else {
-                                                                       if (count($continueList) === 7) {
-                                                                               $contNs = intval($continueList[4]);
-                                                                               if (($contNs !== 0 || $continueList[4] === '0') && !empty ($continueList[5])) {
-                                                                                       $this->contTitle = Title :: makeTitleSafe($contNs, $continueList[5]);
-
-                                                                                       $contID = intval($continueList[6]);
-                                                                                       if ($contID !== 0 || $continueList[6] === '0') {
-                                                                                               $this->contID = $contID;
-                                                                                               return; // done
-                                                                                       }
-                                                                               }
-                                                                       }
-                                                               }
-                                                       }
-                                               }
-                                       }
-                               }
-                       }
-               } else {
-                       //
-                       // expected non-redirect-mode parameter:
-                       // ns|db_key|id
-                       // ns+db_key -- the root title
-                       // id = last page_id to continue from
-                       //
-                       if (count($continueList) === 3) {
-                               $rootNs = intval($continueList[0]);
-                               if (($rootNs !== 0 || $continueList[0] === '0') && !empty ($continueList[1])) {
-                                       $this->rootTitle = Title :: makeTitleSafe($rootNs, $continueList[1]);
-                                       if ($this->rootTitle) {
-
-                                               $contID = intval($continueList[2]);
-                                               if ($contID !== 0) {
-                                                       $this->contID = $contID;
-                                                       return; // done
-                                               }
-                                       }
-                               }
-                       }
-               }
-
-               $this->dieUsage("Invalid continue param. You should pass the original value returned by the previous query", "_badcontinue");
+               // expected format:
+               // ns | key | id1 [| id2]
+               // ns+key: root title
+               // id1: first-level page ID to continue from
+               // id2: second-level page ID to continue from
+               
+               // null stuff out now so we know what's set and what isn't
+               $this->rootTitle = $this->contID = $this->redirID = null;
+               $rootNs = intval($continueList[0]);
+               if($rootNs === 0 && $continueList[0] !== '0')
+                       // Illegal continue parameter
+                       $this->dieUsage("Invalid continue param. You should pass the original value returned by the previous query", "_badcontinue");
+               $this->rootTitle = Title::makeTitleSafe($rootNs, $continueList[1]);
+               if(!$this->rootTitle)
+                       $this->dieUsage("Invalid continue param. You should pass the original value returned by the previous query", "_badcontinue");
+               $contID = intval($continueList[2]);
+               if($contID === 0 && $continueList[2] !== '0')
+                       $this->dieUsage("Invalid continue param. You should pass the original value returned by the previous query", "_badcontinue");
+               $this->contID = $contID;
+               $redirID = intval(@$continueList[3]);
+               if($redirID === 0 && @$continueList[3] !== '0')
+                       // This one isn't required
+                       return;
+               $this->redirID = $redirID;
+               
        }
 
        protected function getContinueStr($lastPageID) {
@@ -306,13 +311,8 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                '|' . $lastPageID;
        }
 
-       protected function getContinueRedirStr($isRedirPhase, $level, $ns, $title, $lastPageID) {
-               return $this->rootTitle->getNamespace() .
-               '|' . $this->rootTitle->getDBkey() .
-               '|' . ($isRedirPhase ? 1 : 2) .
-               '|' . $level .
-                ($level > 0 ? ('|' . $ns . '|' . $title) : '') .
-               '|' . $lastPageID;
+       protected function getContinueRedirStr($lastPageID, $lastRedirID) {
+               return $this->getContinueStr($lastPageID) . '|' . $lastRedirID;
        }
 
        public function getAllowedParams() {
@@ -349,8 +349,8 @@ class ApiQueryBacklinks extends ApiQueryGeneratorBase {
                        'continue' => 'When more results are available, use this to continue.',
                        'namespace' => 'The namespace to enumerate.',
                        'filterredir' => 'How to filter for redirects',
-                       'redirect' => 'If linking page is a redirect, find all pages that link to that redirect (not implemented)',
-                       'limit' => 'How many total pages to return.'
+                       'redirect' => 'If linking page is a redirect, find all pages that link to that redirect as well. Maximum limit is halved.',
+                       'limit' => "How many total pages to return. If {$this->bl_code}redirect is enabled, limit applies to each level separately."
                );
        }