/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
package org.teiid.translator.solr;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.solr.client.solrj.SolrQuery;
import org.apache.solr.client.solrj.response.QueryResponse;
import org.apache.solr.common.SolrDocument;
import org.apache.solr.common.SolrDocumentList;
import org.teiid.language.Command;
import org.teiid.language.QueryExpression;
import org.teiid.logging.LogManager;
import org.teiid.metadata.RuntimeMetadata;
import org.teiid.translator.DataNotAvailableException;
import org.teiid.translator.ExecutionContext;
import org.teiid.translator.ResultSetExecution;
import org.teiid.translator.TranslatorException;
public class SolrQueryExecution implements ResultSetExecution {
private ExecutionContext executionContext;
private SolrConnection connection;
private SolrSQLHierarchyVistor visitor;
private Iterator<SolrDocument> resultsItr;
private Class<?>[] expectedTypes;
private SolrExecutionFactory executionFactory;
private int offset = 0;
private Long resultSize;
public SolrQueryExecution(SolrExecutionFactory ef, Command command,
ExecutionContext executionContext, RuntimeMetadata metadata,
SolrConnection connection) {
this.executionFactory = ef;
this.executionContext = executionContext;
this.connection = connection;
if (command instanceof QueryExpression) {
this.expectedTypes = ((QueryExpression)command).getColumnTypes();
}
this.visitor = new SolrSQLHierarchyVistor(metadata, this.executionFactory);
this.visitor.visitNode(command);
}
@Override
public void execute() throws TranslatorException {
LogManager.logDetail("Solr Source Query:", this.visitor.getSolrQuery()); //$NON-NLS-1$
nextBatch();
}
public void nextBatch() throws TranslatorException {
SolrQuery query = this.visitor.getSolrQuery();
if (!this.visitor.isLimitInUse()) {
query.setStart(this.offset);
query.setRows(this.executionContext.getBatchSize());
}
QueryResponse queryResponse = connection.query(this.visitor.getSolrQuery());
SolrDocumentList docList = queryResponse.getResults();
this.resultSize = docList.getNumFound();
this.resultsItr = docList.iterator();
}
/*
* This iterates through the documents from Solr and maps their fields to
* rows in the Teiid table
*
* @see org.teiid.translator.ResultSetExecution#next()
*/
@Override
public List<?> next() throws TranslatorException, DataNotAvailableException {
final List<Object> row = new ArrayList<Object>();
if (this.visitor.isCountStarInUse() && this.resultsItr != null) {
row.add(this.resultSize);
this.resultsItr = null;
return row;
}
// is there any solr docs
if (this.resultsItr != null && this.resultsItr.hasNext()) {
SolrDocument doc = this.resultsItr.next();
for (int i = 0; i < this.visitor.getFieldNameList().size(); i++) {
String columnName = this.visitor.getFieldNameList().get(i);
Object obj = doc.getFieldValue(columnName);
row.add(this.executionFactory.convertFromSolrType(obj, this.expectedTypes[i]));
}
this.offset++;
// if we are at the end of the current cursor set, then get next ones.
if (!this.resultsItr.hasNext() && !this.visitor.isLimitInUse()) {
nextBatch();
}
return row;
}
return null;
}
interface SolrDocumentCallback {
void walk(SolrDocument doc);
}
public void walkDocuments(SolrDocumentCallback callback) throws TranslatorException {
while(this.resultsItr != null && this.resultsItr.hasNext()) {
SolrDocument doc = this.resultsItr.next();
callback.walk(doc);
this.offset++;
// if we are at the end of the current cursor set, then get next ones.
if (!this.resultsItr.hasNext()) {
nextBatch();
}
}
}
@Override
public void close() {
}
@Override
public void cancel() throws TranslatorException {
}
}