WikiSearchEngine.java

/*
 * Copyright (c) 2002-2023, City of Paris
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  1. Redistributions of source code must retain the above copyright notice
 *     and the following disclaimer.
 *
 *  2. Redistributions in binary form must reproduce the above copyright notice
 *     and the following disclaimer in the documentation and/or other materials
 *     provided with the distribution.
 *
 *  3. Neither the name of 'Mairie de Paris' nor 'Lutece' nor the names of its
 *     contributors may be used to endorse or promote products derived from
 *     this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * License 1.0
 */
package fr.paris.lutece.plugins.wiki.search;

import fr.paris.lutece.portal.service.search.IndexationService;
import fr.paris.lutece.portal.service.search.LuceneSearchEngine;
import fr.paris.lutece.portal.service.search.SearchEngine;
import fr.paris.lutece.portal.service.search.SearchItem;
import fr.paris.lutece.portal.service.search.SearchResult;
import fr.paris.lutece.portal.service.util.AppLogService;
import fr.paris.lutece.portal.web.l10n.LocaleService;

import org.apache.lucene.document.DateTools;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;

import java.text.ParseException;

import java.util.ArrayList;
import java.util.List;

import javax.servlet.http.HttpServletRequest;

/**
 * WikiSearchEngine
 */
public class WikiSearchEngine implements SearchEngine
{
    /**
     * Return search results
     * 
     * @param strQuery
     *            The search query
     * @param request
     *            The HTTP request
     * @return Results as a collection of SearchResult
     */
    @Override
    public List<SearchResult> getSearchResults( String strQuery, HttpServletRequest request )
    {
        ArrayList<SearchItem> listResults = new ArrayList<>( );
        IndexSearcher searcher;

        try ( Directory directory = IndexationService.getDirectoryIndex( ) ; IndexReader reader = DirectoryReader.open( directory ) ; )
        {
            searcher = new IndexSearcher( reader );

            BooleanQuery.Builder queryBuilder = new BooleanQuery.Builder( );

            // Contents
            if ( ( strQuery != null ) && !strQuery.equals( "" ) )
            {
                QueryParser parser = new QueryParser( SearchItem.FIELD_CONTENTS, IndexationService.getAnalyser( ) );
                strQuery = strQuery + " OR " + SearchItem.FIELD_TITLE + ":(" + strQuery + ")";
                queryBuilder.add( parser.parse( strQuery ), BooleanClause.Occur.MUST );
            }

            // Language
            String strLanguage = LocaleService.getContextUserLocale( request ).getLanguage( );
            Query queryLanguage = new TermQuery( new Term( SearchItem.FIELD_METADATA, strLanguage ) );
            queryBuilder.add( queryLanguage, BooleanClause.Occur.MUST );

            // Type
            Query queryType = new TermQuery( new Term( SearchItem.FIELD_TYPE, WikiIndexer.getDocumentType( ) ) );
            queryBuilder.add( queryType, BooleanClause.Occur.MUST );

            // Get results documents
            TopDocs topDocs = searcher.search( queryBuilder.build( ), LuceneSearchEngine.MAX_RESPONSES );
            ScoreDoc [ ] hits = topDocs.scoreDocs;

            for ( int i = 0; i < hits.length; i++ )
            {
                int docId = hits [i].doc;
                Document document = searcher.doc( docId );
                SearchItem item = new SearchItem( document );
                listResults.add( item );
            }
        }
        catch( Exception e )
        {
            AppLogService.error( e.getMessage( ), e );
        }

        return convertList( listResults );
    }

    /**
     * Convert a list of Lucene items into a list of generic search items
     * 
     * @param listSource
     *            The list of Lucene items
     * @return A list of generic search items
     */
    private List<SearchResult> convertList( List<SearchItem> listSource )
    {
        List<SearchResult> listDest = new ArrayList<>( );

        for ( SearchItem item : listSource )
        {
            SearchResult result = new SearchResult( );
            result.setId( item.getId( ) );

            try
            {
                result.setDate( DateTools.stringToDate( item.getDate( ) ) );
            }
            catch( ParseException e )
            {
                AppLogService.error( "Bad Date Format for indexed item \"" + item.getTitle( ) + "\" : " + e.getMessage( ) );
            }

            result.setUrl( item.getUrl( ) );
            result.setTitle( item.getTitle( ) );
            result.setSummary( item.getSummary( ) );
            result.setType( item.getType( ) );
            listDest.add( result );
        }

        return listDest;
    }
}