wiki.techinc.nl/includes/PrefixSearch.php
Nik Everett eb68807367 Add hook to extract namespace in prefix search
This will allow extensions (namely CirrusSearch) to match namespaces using
their own rules if core can't find the namespace on its own.

Bug: 62322
Change-Id: I17337cd8ce90190bd335c9159e9d3bbb39ba89cd
2014-10-22 16:05:19 -04:00

357 lines
11 KiB
PHP

<?php
/**
* Prefix search of page names.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
*/
/**
* Handles searching prefixes of titles and finding any page
* names that match. Used largely by the OpenSearch implementation.
*
* @ingroup Search
*/
abstract class PrefixSearch {
/**
* Do a prefix search of titles and return a list of matching page names.
* @deprecated Since 1.23, use TitlePrefixSearch or StringPrefixSearch classes
*
* @param string $search
* @param int $limit
* @param array $namespaces Used if query is not explicitly prefixed
* @return array Array of strings
*/
public static function titleSearch( $search, $limit, $namespaces = array() ) {
$prefixSearch = new StringPrefixSearch;
return $prefixSearch->search( $search, $limit, $namespaces );
}
/**
* Do a prefix search of titles and return a list of matching page names.
*
* @param string $search
* @param int $limit
* @param array $namespaces Used if query is not explicitly prefixed
* @return array Array of strings or Title objects
*/
public function search( $search, $limit, $namespaces = array() ) {
$search = trim( $search );
if ( $search == '' ) {
return array(); // Return empty result
}
$namespaces = $this->validateNamespaces( $namespaces );
// Find a Title which is not an interwiki and is in NS_MAIN
$title = Title::newFromText( $search );
if ( $title && !$title->isExternal() ) {
$ns = array( $title->getNamespace() );
$search = $title->getText();
if ( $ns[0] == NS_MAIN ) {
$ns = $namespaces; // no explicit prefix, use default namespaces
wfRunHooks( 'PrefixSearchExtractNamespace', array( &$ns, &$search ) );
}
return $this->searchBackend( $ns, $search, $limit );
}
// Is this a namespace prefix?
$title = Title::newFromText( $search . 'Dummy' );
if ( $title && $title->getText() == 'Dummy'
&& $title->getNamespace() != NS_MAIN
&& !$title->isExternal() )
{
$namespaces = array( $title->getNamespace() );
$search = '';
} else {
wfRunHooks( 'PrefixSearchExtractNamespace', array( &$namespaces, &$search ) );
}
return $this->searchBackend( $namespaces, $search, $limit );
}
/**
* Do a prefix search for all possible variants of the prefix
* @param string $search
* @param int $limit
* @param array $namespaces
*
* @return array
*/
public function searchWithVariants( $search, $limit, array $namespaces ) {
wfProfileIn( __METHOD__ );
$searches = $this->search( $search, $limit, $namespaces );
// if the content language has variants, try to retrieve fallback results
$fallbackLimit = $limit - count( $searches );
if ( $fallbackLimit > 0 ) {
global $wgContLang;
$fallbackSearches = $wgContLang->autoConvertToAllVariants( $search );
$fallbackSearches = array_diff( array_unique( $fallbackSearches ), array( $search ) );
foreach ( $fallbackSearches as $fbs ) {
$fallbackSearchResult = $this->search( $fbs, $fallbackLimit, $namespaces );
$searches = array_merge( $searches, $fallbackSearchResult );
$fallbackLimit -= count( $fallbackSearchResult );
if ( $fallbackLimit == 0 ) {
break;
}
}
}
wfProfileOut( __METHOD__ );
return $searches;
}
/**
* When implemented in a descendant class, receives an array of Title objects and returns
* either an unmodified array or an array of strings corresponding to titles passed to it.
*
* @param array $titles
* @return array
*/
abstract protected function titles( array $titles );
/**
* When implemented in a descendant class, receives an array of titles as strings and returns
* either an unmodified array or an array of Title objects corresponding to strings received.
*
* @param array $strings
*
* @return array
*/
abstract protected function strings( array $strings );
/**
* Do a prefix search of titles and return a list of matching page names.
* @param array $namespaces
* @param string $search
* @param int $limit
* @return array Array of strings
*/
protected function searchBackend( $namespaces, $search, $limit ) {
if ( count( $namespaces ) == 1 ) {
$ns = $namespaces[0];
if ( $ns == NS_MEDIA ) {
$namespaces = array( NS_FILE );
} elseif ( $ns == NS_SPECIAL ) {
return $this->titles( $this->specialSearch( $search, $limit ) );
}
}
$srchres = array();
if ( wfRunHooks( 'PrefixSearchBackend', array( $namespaces, $search, $limit, &$srchres ) ) ) {
return $this->titles( $this->defaultSearchBackend( $namespaces, $search, $limit ) );
} else {
// Default search backend does proper prefix searching, but custom backends
// may sort based on other algorythms that may cause the exact title match
// to not be in the results or be lower down the list.
// Pick namespace (based on PrefixSearch::defaultSearchBackend)
$ns = in_array( NS_MAIN, $namespaces ) ? NS_MAIN : $namespaces[0];
$t = Title::newFromText( $search, $ns );
if ( $t ) {
// If text is a valid title and is in the search results
$string = $t->getPrefixedText();
$key = array_search( $string, $srchres );
if ( $key !== false ) {
// Move it to the front
$cut = array_splice( $srchres, $key, 1 );
array_unshift( $srchres, $cut[0] );
} elseif ( $t->exists() ) {
// Add it in front
array_unshift( $srchres, $string );
if ( count( $srchres ) > $limit ) {
array_pop( $srchres );
}
}
}
}
return $this->strings( $srchres );
}
/**
* Prefix search special-case for Special: namespace.
*
* @param string $search Term
* @param int $limit Max number of items to return
* @return array
*/
protected function specialSearch( $search, $limit ) {
global $wgContLang;
$searchParts = explode( '/', $search, 2 );
$searchKey = $searchParts[0];
$subpageSearch = isset( $searchParts[1] ) ? $searchParts[1] : null;
// Handle subpage search separately.
if ( $subpageSearch !== null ) {
// Try matching the full search string as a page name
$specialTitle = Title::makeTitleSafe( NS_SPECIAL, $searchKey );
if ( !$specialTitle ) {
return array();
}
$special = SpecialPageFactory::getPage( $specialTitle->getText() );
if ( $special ) {
$subpages = $special->prefixSearchSubpages( $subpageSearch, $limit );
return array_map( function ( $sub ) use ( $specialTitle ) {
return $specialTitle->getSubpage( $sub );
}, $subpages );
} else {
return array();
}
}
# normalize searchKey, so aliases with spaces can be found - bug 25675
$searchKey = str_replace( ' ', '_', $searchKey );
$searchKey = $wgContLang->caseFold( $searchKey );
// Unlike SpecialPage itself, we want the canonical forms of both
// canonical and alias title forms...
$keys = array();
foreach ( SpecialPageFactory::getNames() as $page ) {
$keys[$wgContLang->caseFold( $page )] = $page;
}
foreach ( $wgContLang->getSpecialPageAliases() as $page => $aliases ) {
if ( !in_array( $page, SpecialPageFactory::getNames() ) ) {# bug 20885
continue;
}
foreach ( $aliases as $alias ) {
$keys[$wgContLang->caseFold( $alias )] = $alias;
}
}
ksort( $keys );
$srchres = array();
foreach ( $keys as $pageKey => $page ) {
if ( $searchKey === '' || strpos( $pageKey, $searchKey ) === 0 ) {
// bug 27671: Don't use SpecialPage::getTitleFor() here because it
// localizes its input leading to searches for e.g. Special:All
// returning Spezial:MediaWiki-Systemnachrichten and returning
// Spezial:Alle_Seiten twice when $wgLanguageCode == 'de'
$srchres[] = Title::makeTitleSafe( NS_SPECIAL, $page );
}
if ( count( $srchres ) >= $limit ) {
break;
}
}
return $srchres;
}
/**
* Unless overridden by PrefixSearchBackend hook...
* This is case-sensitive (First character may
* be automatically capitalized by Title::secureAndSpit()
* later on depending on $wgCapitalLinks)
*
* @param array $namespaces Namespaces to search in
* @param string $search Term
* @param int $limit Max number of items to return
* @return array Array of Title objects
*/
protected function defaultSearchBackend( $namespaces, $search, $limit ) {
$ns = array_shift( $namespaces ); // support only one namespace
if ( in_array( NS_MAIN, $namespaces ) ) {
$ns = NS_MAIN; // if searching on many always default to main
}
$t = Title::newFromText( $search, $ns );
$prefix = $t ? $t->getDBkey() : '';
$dbr = wfGetDB( DB_SLAVE );
$res = $dbr->select( 'page',
array( 'page_id', 'page_namespace', 'page_title' ),
array(
'page_namespace' => $ns,
'page_title ' . $dbr->buildLike( $prefix, $dbr->anyString() )
),
__METHOD__,
array( 'LIMIT' => $limit, 'ORDER BY' => 'page_title' )
);
$srchres = array();
foreach ( $res as $row ) {
$srchres[] = Title::newFromRow( $row );
}
return $srchres;
}
/**
* Validate an array of numerical namespace indexes
*
* @param array $namespaces
* @return array (default: contains only NS_MAIN)
*/
protected function validateNamespaces( $namespaces ) {
global $wgContLang;
// We will look at each given namespace against wgContLang namespaces
$validNamespaces = $wgContLang->getNamespaces();
if ( is_array( $namespaces ) && count( $namespaces ) > 0 ) {
$valid = array();
foreach ( $namespaces as $ns ) {
if ( is_numeric( $ns ) && array_key_exists( $ns, $validNamespaces ) ) {
$valid[] = $ns;
}
}
if ( count( $valid ) > 0 ) {
return $valid;
}
}
return array( NS_MAIN );
}
}
/**
* Performs prefix search, returning Title objects
* @ingroup Search
*/
class TitlePrefixSearch extends PrefixSearch {
protected function titles( array $titles ) {
return $titles;
}
protected function strings( array $strings ) {
$titles = array_map( 'Title::newFromText', $strings );
$lb = new LinkBatch( $titles );
$lb->setCaller( __METHOD__ );
$lb->execute();
return $titles;
}
}
/**
* Performs prefix search, returning strings
* @ingroup Search
*/
class StringPrefixSearch extends PrefixSearch {
protected function titles( array $titles ) {
return array_map( function ( Title $t ) {
return $t->getPrefixedText();
}, $titles );
}
protected function strings( array $strings ) {
return $strings;
}
}