/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.lucene.index;
import java.io.IOException;
import java.util.BitSet;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.apache.lucene.analysis.MockAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.store.Directory;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.LuceneTestCase;
/**
* Test class to illustrate using IndexDeletionPolicy to provide multi-level rollback capability.
* This test case creates an index of records 1 to 100, introducing a commit point every 10 records.
*
* A "keep all" deletion policy is used to ensure we keep all commit points for testing purposes
*/
public class TestTransactionRollback extends LuceneTestCase {
private static final String FIELD_RECORD_ID = "record_id";
private Directory dir;
//Rolls back index to a chosen ID
private void rollBackLast(int id) throws Exception {
// System.out.println("Attempting to rollback to "+id);
String ids="-"+id;
IndexCommit last=null;
Collection<IndexCommit> commits = DirectoryReader.listCommits(dir);
for (Iterator<IndexCommit> iterator = commits.iterator(); iterator.hasNext();) {
IndexCommit commit = iterator.next();
Map<String,String> ud=commit.getUserData();
if (ud.size() > 0) {
if (ud.get("index").endsWith(ids)) {
last = commit;
}
}
}
if (last==null) {
throw new RuntimeException("Couldn't find commit point "+id);
}
IndexWriter w = new IndexWriter(dir, newIndexWriterConfig(new MockAnalyzer(random()))
.setIndexDeletionPolicy(new RollbackDeletionPolicy(id))
.setIndexCommit(last));
Map<String,String> data = new HashMap<>();
data.put("index", "Rolled back to 1-"+id);
w.setLiveCommitData(data.entrySet());
w.close();
}
public void testRepeatedRollBacks() throws Exception {
int expectedLastRecordId = 100;
while (expectedLastRecordId>10) {
expectedLastRecordId -= 10;
rollBackLast(expectedLastRecordId);
BitSet expecteds = new BitSet(100);
expecteds.set(1, (expectedLastRecordId+1), true);
checkExpecteds(expecteds);
}
}
private void checkExpecteds(BitSet expecteds) throws Exception {
IndexReader r = DirectoryReader.open(dir);
//Perhaps not the most efficient approach but meets our
//needs here.
final Bits liveDocs = MultiFields.getLiveDocs(r);
for (int i = 0; i < r.maxDoc(); i++) {
if (liveDocs == null || liveDocs.get(i)) {
String sval=r.document(i).get(FIELD_RECORD_ID);
if(sval!=null) {
int val=Integer.parseInt(sval);
assertTrue("Did not expect document #"+val, expecteds.get(val));
expecteds.set(val,false);
}
}
}
r.close();
assertEquals("Should have 0 docs remaining ", 0 ,expecteds.cardinality());
}
/*
private void showAvailableCommitPoints() throws Exception {
Collection commits = DirectoryReader.listCommits(dir);
for (Iterator iterator = commits.iterator(); iterator.hasNext();) {
IndexCommit comm = (IndexCommit) iterator.next();
System.out.print("\t Available commit point:["+comm.getUserData()+"] files=");
Collection files = comm.getFileNames();
for (Iterator iterator2 = files.iterator(); iterator2.hasNext();) {
String filename = (String) iterator2.next();
System.out.print(filename+", ");
}
System.out.println();
}
}
*/
@Override
public void setUp() throws Exception {
super.setUp();
dir = newDirectory();
//Build index, of records 1 to 100, committing after each batch of 10
IndexDeletionPolicy sdp=new KeepAllDeletionPolicy();
IndexWriter w=new IndexWriter(dir, newIndexWriterConfig(new MockAnalyzer(random()))
.setIndexDeletionPolicy(sdp));
for(int currentRecordId=1;currentRecordId<=100;currentRecordId++) {
Document doc=new Document();
doc.add(newTextField(FIELD_RECORD_ID, ""+currentRecordId, Field.Store.YES));
w.addDocument(doc);
if (currentRecordId%10 == 0) {
Map<String,String> data = new HashMap<>();
data.put("index", "records 1-"+currentRecordId);
w.setLiveCommitData(data.entrySet());
w.commit();
}
}
w.close();
}
@Override
public void tearDown() throws Exception {
dir.close();
super.tearDown();
}
// Rolls back to previous commit point
static class RollbackDeletionPolicy extends IndexDeletionPolicy {
private int rollbackPoint;
public RollbackDeletionPolicy(int rollbackPoint) {
this.rollbackPoint = rollbackPoint;
}
@Override
public void onCommit(List<? extends IndexCommit> commits) throws IOException {
}
@Override
public void onInit(List<? extends IndexCommit> commits) throws IOException {
for (final IndexCommit commit : commits) {
Map<String,String> userData=commit.getUserData();
if (userData.size() > 0) {
// Label for a commit point is "Records 1-30"
// This code reads the last id ("30" in this example) and deletes it
// if it is after the desired rollback point
String x = userData.get("index");
String lastVal = x.substring(x.lastIndexOf("-")+1);
int last = Integer.parseInt(lastVal);
if (last>rollbackPoint) {
/*
System.out.print("\tRolling back commit point:" +
" UserData="+commit.getUserData() +") ("+(commits.size()-1)+" commit points left) files=");
Collection files = commit.getFileNames();
for (Iterator iterator2 = files.iterator(); iterator2.hasNext();) {
System.out.print(" "+iterator2.next());
}
System.out.println();
*/
commit.delete();
}
}
}
}
}
static class DeleteLastCommitPolicy extends IndexDeletionPolicy {
@Override
public void onCommit(List<? extends IndexCommit> commits) throws IOException {}
@Override
public void onInit(List<? extends IndexCommit> commits) throws IOException {
commits.get(commits.size()-1).delete();
}
}
public void testRollbackDeletionPolicy() throws Exception {
for(int i=0;i<2;i++) {
// Unless you specify a prior commit point, rollback
// should not work:
new IndexWriter(dir, newIndexWriterConfig(new MockAnalyzer(random()))
.setIndexDeletionPolicy(new DeleteLastCommitPolicy())).close();
IndexReader r = DirectoryReader.open(dir);
assertEquals(100, r.numDocs());
r.close();
}
}
// Keeps all commit points (used to build index)
static class KeepAllDeletionPolicy extends IndexDeletionPolicy {
@Override
public void onCommit(List<? extends IndexCommit> commits) throws IOException {}
@Override
public void onInit(List<? extends IndexCommit> commits) throws IOException {}
}
}