3 * Prefix search of page names.
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24 * Handles searching prefixes of titles and finding any page
25 * names that match. Used largely by the OpenSearch implementation.
26 * @deprecated Since 1.27, Use SearchEngine::defaultPrefixSearch or SearchEngine::completionSearch
30 abstract class PrefixSearch
{
32 * Do a prefix search of titles and return a list of matching page names.
33 * @deprecated Since 1.23, use TitlePrefixSearch or StringPrefixSearch classes
35 * @param string $search
37 * @param array $namespaces Used if query is not explicitly prefixed
38 * @param int $offset How many results to offset from the beginning
39 * @return array Array of strings
41 public static function titleSearch( $search, $limit, $namespaces = [], $offset = 0 ) {
42 $prefixSearch = new StringPrefixSearch
;
43 return $prefixSearch->search( $search, $limit, $namespaces, $offset );
47 * Do a prefix search of titles and return a list of matching page names.
49 * @param string $search
51 * @param array $namespaces Used if query is not explicitly prefixed
52 * @param int $offset How many results to offset from the beginning
53 * @return array Array of strings or Title objects
55 public function search( $search, $limit, $namespaces = [], $offset = 0 ) {
56 $search = trim( $search );
57 if ( $search == '' ) {
58 return []; // Return empty result
61 $hasNamespace = SearchEngine
::parseNamespacePrefixes( $search, false, true );
62 if ( $hasNamespace !== false ) {
63 list( $search, $namespaces ) = $hasNamespace;
66 return $this->searchBackend( $namespaces, $search, $limit, $offset );
70 * Do a prefix search for all possible variants of the prefix
71 * @param string $search
73 * @param array $namespaces
74 * @param int $offset How many results to offset from the beginning
78 public function searchWithVariants( $search, $limit, array $namespaces, $offset = 0 ) {
79 $searches = $this->search( $search, $limit, $namespaces, $offset );
81 // if the content language has variants, try to retrieve fallback results
82 $fallbackLimit = $limit - count( $searches );
83 if ( $fallbackLimit > 0 ) {
86 $fallbackSearches = $wgContLang->autoConvertToAllVariants( $search );
87 $fallbackSearches = array_diff( array_unique( $fallbackSearches ), [ $search ] );
89 foreach ( $fallbackSearches as $fbs ) {
90 $fallbackSearchResult = $this->search( $fbs, $fallbackLimit, $namespaces );
91 $searches = array_merge( $searches, $fallbackSearchResult );
92 $fallbackLimit -= count( $fallbackSearchResult );
94 if ( $fallbackLimit == 0 ) {
103 * When implemented in a descendant class, receives an array of Title objects and returns
104 * either an unmodified array or an array of strings corresponding to titles passed to it.
106 * @param array $titles
109 abstract protected function titles( array $titles );
112 * When implemented in a descendant class, receives an array of titles as strings and returns
113 * either an unmodified array or an array of Title objects corresponding to strings received.
115 * @param array $strings
119 abstract protected function strings( array $strings );
122 * Do a prefix search of titles and return a list of matching page names.
123 * @param array $namespaces
124 * @param string $search
126 * @param int $offset How many results to offset from the beginning
127 * @return array Array of strings
129 protected function searchBackend( $namespaces, $search, $limit, $offset ) {
130 if ( count( $namespaces ) == 1 ) {
131 $ns = $namespaces[0];
132 if ( $ns == NS_MEDIA
) {
133 $namespaces = [ NS_FILE
];
134 } elseif ( $ns == NS_SPECIAL
) {
135 return $this->titles( $this->specialSearch( $search, $limit, $offset ) );
140 'PrefixSearchBackend',
141 [ $namespaces, $search, $limit, &$srchres, $offset ]
143 return $this->titles( $this->defaultSearchBackend( $namespaces, $search, $limit, $offset ) );
145 return $this->strings(
146 $this->handleResultFromHook( $srchres, $namespaces, $search, $limit, $offset ) );
149 private function handleResultFromHook( $srchres, $namespaces, $search, $limit, $offset ) {
150 if ( $offset === 0 ) {
151 // Only perform exact db match if offset === 0
152 // This is still far from perfect but at least we avoid returning the
153 // same title afain and again when the user is scrolling with a query
154 // that matches a title in the db.
155 $rescorer = new SearchExactMatchRescorer();
156 $srchres = $rescorer->rescore( $search, $namespaces, $srchres, $limit );
162 * Prefix search special-case for Special: namespace.
164 * @param string $search Term
165 * @param int $limit Max number of items to return
166 * @param int $offset Number of items to offset
169 protected function specialSearch( $search, $limit, $offset ) {
172 $searchParts = explode( '/', $search, 2 );
173 $searchKey = $searchParts[0];
174 $subpageSearch = $searchParts[1] ??
null;
176 // Handle subpage search separately.
177 if ( $subpageSearch !== null ) {
178 // Try matching the full search string as a page name
179 $specialTitle = Title
::makeTitleSafe( NS_SPECIAL
, $searchKey );
180 if ( !$specialTitle ) {
183 $special = SpecialPageFactory
::getPage( $specialTitle->getText() );
185 $subpages = $special->prefixSearchSubpages( $subpageSearch, $limit, $offset );
186 return array_map( function ( $sub ) use ( $specialTitle ) {
187 return $specialTitle->getSubpage( $sub );
194 # normalize searchKey, so aliases with spaces can be found - T27675
195 $searchKey = str_replace( ' ', '_', $searchKey );
196 $searchKey = $wgContLang->caseFold( $searchKey );
198 // Unlike SpecialPage itself, we want the canonical forms of both
199 // canonical and alias title forms...
201 foreach ( SpecialPageFactory
::getNames() as $page ) {
202 $keys[$wgContLang->caseFold( $page )] = [ 'page' => $page, 'rank' => 0 ];
205 foreach ( $wgContLang->getSpecialPageAliases() as $page => $aliases ) {
206 if ( !in_array( $page, SpecialPageFactory
::getNames() ) ) {# T22885
210 foreach ( $aliases as $key => $alias ) {
211 $keys[$wgContLang->caseFold( $alias )] = [ 'page' => $alias, 'rank' => $key ];
217 foreach ( $keys as $pageKey => $page ) {
218 if ( $searchKey === '' ||
strpos( $pageKey, $searchKey ) === 0 ) {
219 // T29671: Don't use SpecialPage::getTitleFor() here because it
220 // localizes its input leading to searches for e.g. Special:All
221 // returning Spezial:MediaWiki-Systemnachrichten and returning
222 // Spezial:Alle_Seiten twice when $wgLanguageCode == 'de'
223 $matches[$page['rank']][] = Title
::makeTitleSafe( NS_SPECIAL
, $page['page'] );
225 if ( isset( $matches[0] ) && count( $matches[0] ) >= $limit +
$offset ) {
226 // We have enough items in primary rank, no use to continue
233 // Ensure keys are in order
236 $matches = array_reduce( $matches, 'array_merge', [] );
238 return array_slice( $matches, $offset, $limit );
242 * Unless overridden by PrefixSearchBackend hook...
243 * This is case-sensitive (First character may
244 * be automatically capitalized by Title::secureAndSpit()
245 * later on depending on $wgCapitalLinks)
247 * @param array|null $namespaces Namespaces to search in
248 * @param string $search Term
249 * @param int $limit Max number of items to return
250 * @param int $offset Number of items to skip
251 * @return Title[] Array of Title objects
253 public function defaultSearchBackend( $namespaces, $search, $limit, $offset ) {
254 // Backwards compatability with old code. Default to NS_MAIN if no namespaces provided.
255 if ( $namespaces === null ) {
258 if ( !$namespaces ) {
259 $namespaces[] = NS_MAIN
;
262 // Construct suitable prefix for each namespace. They differ in cases where
263 // some namespaces always capitalize and some don't.
265 foreach ( $namespaces as $namespace ) {
266 // For now, if special is included, ignore the other namespaces
267 if ( $namespace == NS_SPECIAL
) {
268 return $this->specialSearch( $search, $limit, $offset );
271 $title = Title
::makeTitleSafe( $namespace, $search );
272 // Why does the prefix default to empty?
273 $prefix = $title ?
$title->getDBkey() : '';
274 $prefixes[$prefix][] = $namespace;
277 $dbr = wfGetDB( DB_REPLICA
);
278 // Often there is only one prefix that applies to all requested namespaces,
279 // but sometimes there are two if some namespaces do not always capitalize.
281 foreach ( $prefixes as $prefix => $namespaces ) {
283 'page_namespace' => $namespaces,
284 'page_title' . $dbr->buildLike( $prefix, $dbr->anyString() ),
286 $conds[] = $dbr->makeList( $condition, LIST_AND
);
290 $fields = [ 'page_id', 'page_namespace', 'page_title' ];
291 $conds = $dbr->makeList( $conds, LIST_OR
);
294 'ORDER BY' => [ 'page_title', 'page_namespace' ],
298 $res = $dbr->select( $table, $fields, $conds, __METHOD__
, $options );
300 return iterator_to_array( TitleArray
::newFromResult( $res ) );
304 * Validate an array of numerical namespace indexes
306 * @param array $namespaces
307 * @return array (default: contains only NS_MAIN)
309 protected function validateNamespaces( $namespaces ) {
312 // We will look at each given namespace against wgContLang namespaces
313 $validNamespaces = $wgContLang->getNamespaces();
314 if ( is_array( $namespaces ) && count( $namespaces ) > 0 ) {
316 foreach ( $namespaces as $ns ) {
317 if ( is_numeric( $ns ) && array_key_exists( $ns, $validNamespaces ) ) {
321 if ( count( $valid ) > 0 ) {
331 * Performs prefix search, returning Title objects
332 * @deprecated Since 1.27, Use SearchEngine::defaultPrefixSearch or SearchEngine::completionSearch
335 class TitlePrefixSearch
extends PrefixSearch
{
337 protected function titles( array $titles ) {
341 protected function strings( array $strings ) {
342 $titles = array_map( 'Title::newFromText', $strings );
343 $lb = new LinkBatch( $titles );
344 $lb->setCaller( __METHOD__
);
351 * Performs prefix search, returning strings
352 * @deprecated Since 1.27, Use SearchEngine::prefixSearchSubpages or SearchEngine::completionSearch
355 class StringPrefixSearch
extends PrefixSearch
{
357 protected function titles( array $titles ) {
358 return array_map( function ( Title
$t ) {
359 return $t->getPrefixedText();
363 protected function strings( array $strings ) {