Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A class that gets Accession Number, check for uniqueness

 *             and register it into db

 *  Copyright: 2000 Regents of the University of California and the

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Jivka Bojilova, Matt Jones

 *

 *   '$Author: tao $'

 *     '$Date: 2013-04-19 17:47:14 -0700 (Fri, 19 Apr 2013) $'

 * '$Revision: 7595 $'

 *

 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

package edu.ucsb.nceas.metacat.common.query;

import java.io.IOException;

import java.io.InputStream;

import java.net.MalformedURLException;

import java.net.URL;

import java.util.List;

import java.util.Map;

import java.util.Set;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.apache.solr.client.solrj.impl.CommonsHttpSolrServer;

import org.apache.solr.client.solrj.util.ClientUtils;

import org.apache.solr.common.params.SolrParams;

import org.apache.solr.schema.SchemaField;

import org.dataone.service.exceptions.NotFound;

import org.dataone.service.exceptions.NotImplemented;

import org.dataone.service.types.v1.Subject;

/**

 * The query service for the http solr server.

 * @author tao

 *

 */

public class HttpSolrQueryService extends SolrQueryService {

    private String solrServerBaseURL = null;

    private CommonsHttpSolrServer httpSolrServer = null;

    private static Log log = LogFactory.getLog(HttpSolrQueryService.class);

    /**

     * Constructor

     * @param httpSolrServer

     */

    public HttpSolrQueryService(CommonsHttpSolrServer httpSolrServer) {

        if(httpSolrServer == null) {

            throw new NullPointerException("HttpSolrQueryService.constructor - The httpSolrServer parameter can't be null");

        }

        this.httpSolrServer = httpSolrServer;

        this.solrServerBaseURL = httpSolrServer.getBaseURL();

    }

    /**

     * Query the Solr server with specified query string and the user's identity. This is the for the http solr server.

     * It is hard to transform the SolrQueryReponse object to the InputStream object for the HttpSolrServer

     * since the transform needs the SolrCore. We have to open the solr url directly to get the InputStream.

     * @param query the query string

     * @param subjects the user's identity which sent the query

     * @return the response

     * @throws NotFound 

     * @throws IOException 

     * @throws Exception

     */

    public InputStream query(String query, Set<Subject>subjects) throws NotFound, IOException {

        StringBuffer accessFilter = generateAccessFilterParamsString(subjects);

        if(accessFilter != null && accessFilter.length() != 0) {

            query = solrServerBaseURL+"/select?"+query+"&"+FILTERQUERY+"="+accessFilter.toString();

            query = ClientUtils.escapeQueryChars(query);

        } else {

            throw new NotFound("0000", "HttpSolrQueryService.query - There is no identity (even user public) for the user who issued the query");

        }

        log.info("==========HttpSolrQueryService.query - the final url for querying the solr http server is "+query);

        URL url = new URL(query);

        return url.openStream();

    }

    /**

     * Query the Solr server with specified query and user's identity. If the Subjects

     * is null, there will be no access rules for the query. This is for the embedded solr server.

     * @param query the query params. 

     * @param subjects the user's identity which sent the query

     * @return the response

     * @throws Exception

     */

    public  InputStream query(SolrParams query, Set<Subject>subjects) throws Exception {

        throw new NotImplemented("0000", "HttpSolrQueryService - the method of  query(SolrParams query, Set<Subject>subjects) is not for the HttpSolrQueryService. We donot need to implemente it");

    }

    /**

     * Get the fields list of the index schema

     * @return

     * @throws Exception

     */

    public  Map<String, SchemaField> getIndexSchemaFields() throws Exception {

        return null;

    }

    /**

     * Get the version of the solr server.

     * @return

     */

    public String getSolrServerVersion() {

        return null;

    }

}