/*
* 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.accumulo;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.SortedMap;
import java.util.TreeMap;
import org.apache.accumulo.core.client.BatchScanner;
import org.apache.accumulo.core.client.Connector;
import org.apache.accumulo.core.client.IteratorSetting;
import org.apache.accumulo.core.client.Scanner;
import org.apache.accumulo.core.client.TableNotFoundException;
import org.apache.accumulo.core.data.ByteSequence;
import org.apache.accumulo.core.data.Key;
import org.apache.accumulo.core.data.Range;
import org.apache.accumulo.core.data.Value;
import org.apache.accumulo.core.security.Authorizations;
import org.apache.hadoop.io.Text;
import org.teiid.language.Select;
import org.teiid.language.visitor.SQLStringVisitor;
import org.teiid.metadata.Column;
import org.teiid.metadata.RuntimeMetadata;
import org.teiid.metadata.Table;
import org.teiid.translator.DataNotAvailableException;
import org.teiid.translator.ExecutionContext;
import org.teiid.translator.ResultSetExecution;
import org.teiid.translator.TranslatorException;
public class AccumuloQueryExecution implements ResultSetExecution {
private AccumuloConnection connection;
private Iterator<Entry<Key,Value>> results;
private Class<?>[] expectedColumnTypes;
private AccumuloExecutionFactory aef;
private AccumuloQueryVisitor visitor;
private Entry<Key, Value> prevEntry;
public AccumuloQueryExecution(AccumuloExecutionFactory aef, Select command,
ExecutionContext executionContext,
RuntimeMetadata metadata,
AccumuloConnection connection) throws TranslatorException {
this.aef = aef;
this.connection = connection;
this.expectedColumnTypes = command.getColumnTypes();
this.visitor = new AccumuloQueryVisitor(this.aef);
this.visitor.visitNode(command);
if (!visitor.exceptions.isEmpty()) {
throw visitor.exceptions.get(0);
}
}
@Override
public void execute() throws TranslatorException {
try {
Connector connector = this.connection.getInstance();
List<Range> ranges = this.visitor.getRanges();
Table scanTable = this.visitor.getScanTable();
List<IteratorSetting> scanIterators = visitor.scanIterators();
this.results = runQuery(this.aef, connector, this.connection.getAuthorizations(), ranges, scanTable, scanIterators);
} catch (TableNotFoundException e) {
// Teiid will not let the query come this far with out validating metadata for given table
// so table in user's mind exists, it may be not be in the Accumulo, which should be treated as
// now rows.
this.results = null;
}
}
static Iterator<Entry<Key, Value>> runQuery(AccumuloExecutionFactory aef,
Connector connector, Authorizations auths, List<Range> ranges,
Table scanTable, List<IteratorSetting> scanIterators)
throws TableNotFoundException {
if (ranges.size() <= 1) {
Scanner scanner = connector.createScanner(SQLStringVisitor.getRecordName(scanTable), auths);
if (!ranges.isEmpty()) {
scanner.setRange(ranges.get(0));
}
if (scanIterators != null && !scanIterators.isEmpty()) {
for (IteratorSetting it:scanIterators) {
scanner.addScanIterator(it);
}
}
scanner.enableIsolation();
return scanner.iterator();
}
// use batch scanner
BatchScanner scanner = connector.createBatchScanner(SQLStringVisitor.getRecordName(scanTable), auths, aef.getQueryThreadsCount());
scanner.setRanges(ranges);
return scanner.iterator();
}
private SortedMap<Key, Value> readNextRow(){
ByteSequence prevRowId = null;
TreeMap<Key, Value> row = new TreeMap<Key, Value>();
while(this.prevEntry != null || this.results != null && this.results.hasNext()) {
Entry<Key, Value> entry = null;
if (this.prevEntry != null) {
entry = this.prevEntry;
this.prevEntry = null;
}
else {
entry = this.results.next();
}
ByteSequence rowId = entry.getKey().getRowData();
if (prevRowId == null || prevRowId.equals(rowId)) {
prevRowId= rowId;
row.put(entry.getKey(), entry.getValue());
}
else {
this.prevEntry = entry;
return row;
}
}
return row;
}
@Override
public List<?> next() throws TranslatorException, DataNotAvailableException {
SortedMap<Key, Value> rowItems = readNextRow();
boolean rowIdAdded = false;
LinkedHashMap<String, byte[]> values = new LinkedHashMap<String, byte[]>();
for (Key key:rowItems.keySet()) {
Text cf = key.getColumnFamily();
Text cq = key.getColumnQualifier();
Text rowid = key.getRow();
Value value = rowItems.get(key);
Column match = findMatchingColumn(cf, cq);
if (!rowIdAdded) {
values.put(AccumuloMetadataProcessor.ROWID, rowid.getBytes());
rowIdAdded = true;
}
if (match != null) {
String valueIn = match.getProperty(AccumuloMetadataProcessor.VALUE_IN, false);
// failed to use isolated scanner, but this if check will accomplish the same in getting the
// most top value
if (values.get(match.getName()) == null) {
values.put(match.getName(), buildValue(valueIn, cq, value));
}
}
}
return nextRow(values);
}
private Column findMatchingColumn(Text rowCF, Text rowCQ) {
String CF = new String(rowCF.getBytes());
String CQ = new String(rowCQ.getBytes());
Column column = this.visitor.lookupColumn(CF+"/"+CQ); //$NON-NLS-1$
if (column == null) {
// this means CQ is not defined; In this pattern CQ is used for value
column = this.visitor.lookupColumn(CF);
}
return column;
}
private List<?> nextRow(Map<String, byte[]> values) {
if (!values.isEmpty()) {
ArrayList<Object> list = new ArrayList<Object>();
for(int i = 0; i < this.visitor.projectedColumns().size(); i++) {
Column column = this.visitor.projectedColumns().get(i);
String colName = SQLStringVisitor.getRecordName(column);
byte[] value = values.get(colName);
list.add(AccumuloDataTypeManager.deserialize(value, this.expectedColumnTypes[i]));
}
return list;
}
return null;
}
private byte[] buildValue(String pattern, Text cq, Value value) {
if (pattern == null) {
return value.get();
}
pattern = pattern.substring(1, pattern.length()-1); // remove the curleys
if (pattern.equals(AccumuloMetadataProcessor.ValueIn.VALUE.name())) {
return value.get();
}
else if (pattern.equals(AccumuloMetadataProcessor.ValueIn.CQ.name())) {
return cq.getBytes();
}
return null;
}
@Override
public void close() {
}
@Override
public void cancel() throws TranslatorException {
}
}