Auto-forward to search suggestion when zero results

If the user gets zero results, but gets a "Did you mean" result, just
run the query for the "Did you mean" result and inform the user that
this happened. Adds a new query param 'runsuggestion' which will, when
given a falsy value, prevent running the suggestion and give the result
to the original query.

Bug: T105202
Change-Id: I7ed79942c242b1957d46bdcad59985f37466fb83

diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index a755029..8dc37c0 100644 (file)
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -7679,6 +7679,16 @@ $wgVirtualRestConfig = array(
        )
 );
 
+/**
+ * Controls the percentage of zero-result search queries with suggestions that
+ * run the suggestion automatically. Must be a number between 0 and 1.  This
+ * can be lowered to reduce query volume at the expense of result quality.
+ *
+ * @var float
+ * @since 1.26
+ */
+$wgSearchRunSuggestedQueryPercent = 1;
+
 /**
  * For really cool vim folding this needs to be at the end:
  * vim: foldmarker=@{,@} foldmethod=marker

diff --git a/includes/specials/SpecialSearch.php b/includes/specials/SpecialSearch.php
index bc1bb3d..84077e6 100644 (file)
--- a/includes/specials/SpecialSearch.php
+++ b/includes/specials/SpecialSearch.php
@@ -68,6 +68,11 @@ class SpecialSearch extends SpecialPage {
         */
        protected $fulltext;
 
+       /**
+        * @var bool
+        */
+       protected $runSuggestion = true;
+
        const NAMESPACES_CURRENT = 'sense';
 
        public function __construct() {
@@ -169,6 +174,7 @@ class SpecialSearch extends SpecialPage {
                }
 
                $this->fulltext = $request->getVal( 'fulltext' );
+               $this->runSuggestion = (bool)$request->getVal( 'runsuggestion', true );
                $this->profile = $profile;
        }
 
@@ -214,7 +220,6 @@ class SpecialSearch extends SpecialPage {
                $search->setNamespaces( $this->namespaces );
                $search->prefix = $this->mPrefix;
                $term = $search->transformSearchTerm( $term );
-               $didYouMeanHtml = '';
 
                Hooks::run( 'SpecialSearchSetupEngine', array( $this, $this->profile, $search ) );
 
@@ -265,37 +270,17 @@ class SpecialSearch extends SpecialPage {
                }
 
                // did you mean... suggestions
-               if ( $showSuggestion && $textMatches && !$textStatus && $textMatches->hasSuggestion() ) {
-                       # mirror Go/Search behavior of original request ..
-                       $didYouMeanParams = array( 'search' => $textMatches->getSuggestionQuery() );
-
-                       if ( $this->fulltext != null ) {
-                               $didYouMeanParams['fulltext'] = $this->fulltext;
-                       }
-
-                       $stParams = array_merge(
-                               $didYouMeanParams,
-                               $this->powerSearchOptions()
-                       );
-
-                       $suggestionSnippet = $textMatches->getSuggestionSnippet();
-
-                       if ( $suggestionSnippet == '' ) {
-                               $suggestionSnippet = null;
+               $didYouMeanHtml = '';
+               if ( $showSuggestion && $textMatches && !$textStatus ) {
+                       if ( $this->shouldRunSuggestedQuery( $textMatches ) ) {
+                               $newMatches = $search->searchText( $textMatches->getSuggestionQuery() );
+                               if ( $newMatches instanceof SearchResultSet && $newMatches->numRows() > 0 ) {
+                                       $didYouMeanHtml = $this->getDidYouMeanRewrittenHtml( $term, $textMatches );
+                                       $textMatches = $newMatches;
+                               }
+                       } elseif ( $textMatches->hasSuggestion() ) {
+                               $didYouMeanHtml = $this->getDidYouMeanHtml( $textMatches );
                        }
-
-                       $suggestLink = Linker::linkKnown(
-                               $this->getPageTitle(),
-                               $suggestionSnippet,
-                               array(),
-                               $stParams
-                       );
-
-                       # html of did you mean... search suggestion link
-                       $didYouMeanHtml =
-                               Xml::openElement( 'div', array( 'class' => 'searchdidyoumean' ) ) .
-                               $this->msg( 'search-suggest' )->rawParams( $suggestLink )->text() .
-                               Xml::closeElement( 'div' );
                }
 
                if ( !Hooks::run( 'SpecialSearchResultsPrepend', array( $this, $out, $term ) ) ) {
@@ -415,6 +400,99 @@ class SpecialSearch extends SpecialPage {
 
        }
 
+       /**
+        * Decide if the suggested query should be run, and it's results returned
+        * instead of the provided $textMatches
+        *
+        * @param SearchResultSet $textMatches The results of a users query
+        * @return bool
+        */
+       protected function shouldRunSuggestedQuery( SearchResultSet $textMatches ) {
+               global $wgSearchRunSuggestedQueryPercent;
+
+               if ( !$this->runSuggestion ||
+                       !$textMatches->hasSuggestion() ||
+                       $textMatches->numRows() > 0 ||
+                       $textMatches->searchContainedSyntax()
+               ) {
+                       return false;
+               }
+
+               // Generate a random number between 0 and 1. If the
+               // number is less than the desired percentages run it.
+               $rand = rand( 0, getrandmax() ) / getrandmax();
+               return $wgSearchRunSuggestedQueryPercent > $rand;
+       }
+
+       /**
+        * Generates HTML shown to the user when we have a suggestion about a query
+        * that might give more results than their current query.
+        */
+       protected function getDidYouMeanHtml( SearchResultSet $textMatches ) {
+               # mirror Go/Search behavior of original request ..
+               $params = array( 'search' => $textMatches->getSuggestionQuery() );
+               if ( $this->fulltext != null ) {
+                       $params['fulltext'] = $this->fulltext;
+               }
+               $stParams = array_merge( $params, $this->powerSearchOptions() );
+
+               $suggest = Linker::linkKnown(
+                       $this->getPageTitle(),
+                       $textMatches->getSuggestionSnippet() ?: null,
+                       array(),
+                       $stParams
+               );
+
+               # html of did you mean... search suggestion link
+               return Html::rawElement(
+                       'div',
+                       array( 'class' => 'searchdidyoumean' ),
+                       $this->msg( 'search-suggest' )->rawParams( $suggest )->escaped()
+               );
+       }
+
+       /**
+        * Generates HTML shown to user when their query has been internally rewritten,
+        * and the results of the rewritten query are being returned.
+        *
+        * @param string $term The users search input
+        * @param SearchResultSet $textMatches The response to the users initial search request
+        * @return string HTML linking the user to their original $term query, and the one
+        *  suggested by $textMatches.
+        */
+       protected function getDidYouMeanRewrittenHtml( $term, SearchResultSet $textMatches ) {
+               // Showing results for '$rewritten'
+               // Search instead for '$orig'
+
+               $params = array( 'search' => $textMatches->getSuggestionQuery() );
+               if ( $this->fulltext != null ) {
+                       $params['fulltext'] = $this->fulltext;
+               }
+               $stParams = array_merge( $params, $this->powerSearchOptions() );
+
+               $rewritten = Linker::linkKnown(
+                       $this->getPageTitle(),
+                       $textMatches->getSuggestionSnippet() ?: null,
+                       array(),
+                       $stParams
+               );
+
+               $stParams['search'] = $term;
+               $stParams['runsuggestion'] = 0;
+               $original = Linker::linkKnown(
+                       $this->getPageTitle(),
+                       htmlspecialchars( $term ),
+                       array(),
+                       $stParams
+               );
+
+               return Html::rawElement(
+                       'div',
+                       array( 'class' => 'searchdidyoumean' ),
+                       $this->msg( 'search-rewritten')->rawParams( $rewritten, $original )->escaped()
+               );
+       }
+
        /**
         * @param Title $title
         * @param int $num The number of search results found

diff --git a/languages/i18n/en.json b/languages/i18n/en.json
index 0cf41d2..57b4b49 100644 (file)
--- a/languages/i18n/en.json
+++ b/languages/i18n/en.json
@@ -914,6 +914,7 @@
        "search-category": "(category $1)",
        "search-file-match": "(matches file content)",
        "search-suggest": "Did you mean: $1",
+       "search-rewritten": "Showing results for $1. Search instead for $2.",
        "search-interwiki-caption": "Sister projects",
        "search-interwiki-default": "Results from $1:",
        "search-interwiki-custom": "",

diff --git a/languages/i18n/qqq.json b/languages/i18n/qqq.json
index 3bcab84..b0ba9f1 100644 (file)
--- a/languages/i18n/qqq.json
+++ b/languages/i18n/qqq.json
@@ -1084,6 +1084,7 @@
        "search-category": "This text will be shown on the search result listing after the page title of a result if the search algorithm thinks that the page being in a particular category is relevant.\n\nParameters:\n* $1 - the category's name with any matching portion highlighted\n{{Identical|Category}}",
        "search-file-match": "This text will be shown on the search result listing after the page title of a result if the search engine got search results from the contents of files, rather than the pages.",
        "search-suggest": "Used for \"Did you mean\" suggestions:\n* $1 - suggested link",
+       "search-rewritten": "Used when the user is served the results for a query other than what they provided. Parameters:\n* $1 - a link to search for the current result set.* $2 - a link to perform the original search without rewriting.",
        "search-interwiki-caption": "Used in [[Special:Search]], when showing search results from other wikis.",
        "search-interwiki-default": "Parameters:\n* $1 - the hostname of the remote wiki from where the additional results listed below are returned",
        "search-interwiki-custom": "#REDIRECT [[MediaWiki:Wmf-search-interwiki-custom/qqq]]",

diff --git a/tests/phpunit/includes/specials/SpecialSearchTest.php b/tests/phpunit/includes/specials/SpecialSearchTest.php
index 5482b97..7e60fdd 100644 (file)
--- a/tests/phpunit/includes/specials/SpecialSearchTest.php
+++ b/tests/phpunit/includes/specials/SpecialSearchTest.php
@@ -141,4 +141,107 @@ class SpecialSearchTest extends MediaWikiTestCase {
                        "Search term '{$term}' should not be expanded in Special:Search <title>"
                );
        }
+
+       public function provideRewriteQueryWithSuggestion() {
+               return array(
+                       array(
+                               'With results and a suggestion does not run suggested query',
+                               '/Did you mean: <a[^>]+>first suggestion/',
+                               array(
+                                       new SpecialSearchTestMockResultSet( 'first suggestion', array(
+                                               SearchResult::newFromTitle( Title::newMainPage() ),
+                                       ) ),
+                                       new SpecialSearchTestMockResultSet( 'was never run', array() ),
+                               ),
+                       ),
+
+                       array(
+                               'With no results and a suggestion responds with suggested query results',
+                               '/Showing results for <a[^>]+>first suggestion/',
+                               array(
+                                       new SpecialSearchTestMockResultSet( 'first suggestion', array() ),
+                                       new SpecialSearchTestMockResultSet( 'second suggestion', array(
+                                               SearchResult::newFromTitle( Title::newMainPage() ),
+                                       ) ),
+                               ),
+                       ),
+
+                       array(
+                               'When both queries have no results user gets no results',
+                               '/There were no results matching the query/',
+                               array(
+                                       new SpecialSearchTestMockResultSet( 'first suggestion', array() ),
+                                       new SpecialSearchTestMockResultSet( 'second suggestion', array() ),
+                               ),
+                       ),
+               );
+       }
+
+       /**
+        * @dataProvider provideRewriteQueryWithSuggestion
+        */
+       public function testRewriteQueryWithSuggestion( $message, $expectRegex, $fromResults ) {
+               $mockSearchEngine = $this->mockSearchEngine( $fromResults );
+               $search = $this->getMockBuilder( 'SpecialSearch' )
+                       ->setMethods( array( 'getSearchEngine' ) )
+                       ->getMock();
+               $search->expects( $this->any() )
+                       ->method( 'getSearchEngine' )
+                       ->will( $this->returnValue( $mockSearchEngine ) );
+
+               $search->getContext()->setTitle( Title::makeTitle( NS_SPECIAL, 'Search' ) );
+               $search->load();
+               $search->showResults( 'this is a fake search' );
+
+               $html = $search->getContext()->getOutput()->getHTML();
+               foreach ( (array)$expectRegex as $regex ) {
+                       $this->assertRegExp( $regex, $html, $message );
+               }
+       }
+
+       protected function mockSearchEngine( array $returnValues ) {
+               $mock = $this->getMockBuilder( 'SearchEngine' )
+                       ->setMethods( array( 'searchText' ) )
+                       ->getMock();
+
+               $mock->expects( $this->any() )
+                       ->method( 'searchText' )
+                       ->will( call_user_func_array(
+                               array( $this, 'onConsecutiveCalls' ),
+                               array_map( array( $this, 'returnValue' ), $returnValues )
+                       ) );
+
+               return $mock;
+       }
+}
+
+class SpecialSearchTestMockResultSet extends SearchResultSet {
+       protected $results;
+       protected $suggestion;
+
+       public function __construct( $suggestion = null, array $results = array(), $containedSyntax = false) {
+               $this->results = $results;
+               $this->suggestion = $suggestion;
+               $this->containedSyntax = $containedSyntax;
+       }
+
+       public function numRows() {
+               return count( $this->results );
+       }
+
+       public function getTotalHits() {
+               return $this->numRows();
+       }
+
+       public function hasSuggestion() {
+               return $this->suggestion !== null;
+       }
+
+       public function getSuggestionQuery() {
+               return $this->suggestion;
+       }
+
+       public function getSuggestionSnippet() {
+               return $this->suggestion;
+       }
 }