package org.apache.lucene.replicator;
/*
* 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.
*/
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.lucene.facet.taxonomy.directory.DirectoryTaxonomyWriter;
import org.apache.lucene.facet.taxonomy.writercache.TaxonomyWriterCache;
import org.apache.lucene.index.IndexCommit;
import org.apache.lucene.index.IndexDeletionPolicy;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.index.SnapshotDeletionPolicy;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.IOContext;
/**
* A {@link Revision} of a single index and taxonomy index files which comprises
* the list of files from both indexes. This revision should be used whenever a
* pair of search and taxonomy indexes need to be replicated together to
* guarantee consistency of both on the replicating (client) side.
*
* @see IndexRevision
*
* @lucene.experimental
*/
public class IndexAndTaxonomyRevision implements Revision {
/**
* A {@link DirectoryTaxonomyWriter} which sets the underlying
* {@link IndexWriter}'s {@link IndexDeletionPolicy} to
* {@link SnapshotDeletionPolicy}.
*/
public static final class SnapshotDirectoryTaxonomyWriter extends DirectoryTaxonomyWriter {
private SnapshotDeletionPolicy sdp;
private IndexWriter writer;
/**
* @see DirectoryTaxonomyWriter#DirectoryTaxonomyWriter(Directory,
* IndexWriterConfig.OpenMode, TaxonomyWriterCache)
*/
public SnapshotDirectoryTaxonomyWriter(Directory directory, OpenMode openMode, TaxonomyWriterCache cache)
throws IOException {
super(directory, openMode, cache);
}
/** @see DirectoryTaxonomyWriter#DirectoryTaxonomyWriter(Directory, IndexWriterConfig.OpenMode) */
public SnapshotDirectoryTaxonomyWriter(Directory directory, OpenMode openMode) throws IOException {
super(directory, openMode);
}
/** @see DirectoryTaxonomyWriter#DirectoryTaxonomyWriter(Directory) */
public SnapshotDirectoryTaxonomyWriter(Directory d) throws IOException {
super(d);
}
@Override
protected IndexWriterConfig createIndexWriterConfig(OpenMode openMode) {
IndexWriterConfig conf = super.createIndexWriterConfig(openMode);
sdp = new SnapshotDeletionPolicy(conf.getIndexDeletionPolicy());
conf.setIndexDeletionPolicy(sdp);
return conf;
}
@Override
protected IndexWriter openIndexWriter(Directory directory, IndexWriterConfig config) throws IOException {
writer = super.openIndexWriter(directory, config);
return writer;
}
/** Returns the {@link SnapshotDeletionPolicy} used by the underlying {@link IndexWriter}. */
public SnapshotDeletionPolicy getDeletionPolicy() {
return sdp;
}
/** Returns the {@link IndexWriter} used by this {@link DirectoryTaxonomyWriter}. */
public IndexWriter getIndexWriter() {
return writer;
}
}
private static final int RADIX = 16;
public static final String INDEX_SOURCE = "index";
public static final String TAXONOMY_SOURCE = "taxo";
private final IndexWriter indexWriter;
private final SnapshotDirectoryTaxonomyWriter taxoWriter;
private final IndexCommit indexCommit, taxoCommit;
private final SnapshotDeletionPolicy indexSDP, taxoSDP;
private final String version;
private final Map<String,List<RevisionFile>> sourceFiles;
/** Returns a singleton map of the revision files from the given {@link IndexCommit}. */
public static Map<String, List<RevisionFile>> revisionFiles(IndexCommit indexCommit, IndexCommit taxoCommit)
throws IOException {
HashMap<String,List<RevisionFile>> files = new HashMap<String,List<RevisionFile>>();
files.put(INDEX_SOURCE, IndexRevision.revisionFiles(indexCommit).values().iterator().next());
files.put(TAXONOMY_SOURCE, IndexRevision.revisionFiles(taxoCommit).values().iterator().next());
return files;
}
/**
* Returns a String representation of a revision's version from the given
* {@link IndexCommit}s of the search and taxonomy indexes.
*/
public static String revisionVersion(IndexCommit indexCommit, IndexCommit taxoCommit) {
return Long.toString(indexCommit.getGeneration(), RADIX) + ":" + Long.toString(taxoCommit.getGeneration(), RADIX);
}
/**
* Constructor over the given {@link IndexWriter}. Uses the last
* {@link IndexCommit} found in the {@link Directory} managed by the given
* writer.
*/
public IndexAndTaxonomyRevision(IndexWriter indexWriter, SnapshotDirectoryTaxonomyWriter taxoWriter)
throws IOException {
IndexDeletionPolicy delPolicy = indexWriter.getConfig().getIndexDeletionPolicy();
if (!(delPolicy instanceof SnapshotDeletionPolicy)) {
throw new IllegalArgumentException("IndexWriter must be created with SnapshotDeletionPolicy");
}
this.indexWriter = indexWriter;
this.taxoWriter = taxoWriter;
this.indexSDP = (SnapshotDeletionPolicy) delPolicy;
this.taxoSDP = taxoWriter.getDeletionPolicy();
this.indexCommit = indexSDP.snapshot();
this.taxoCommit = taxoSDP.snapshot();
this.version = revisionVersion(indexCommit, taxoCommit);
this.sourceFiles = revisionFiles(indexCommit, taxoCommit);
}
@Override
public int compareTo(String version) {
final String[] parts = version.split(":");
final long indexGen = Long.parseLong(parts[0], RADIX);
final long taxoGen = Long.parseLong(parts[1], RADIX);
final long indexCommitGen = indexCommit.getGeneration();
final long taxoCommitGen = taxoCommit.getGeneration();
// if the index generation is not the same as this commit's generation,
// compare by it. Otherwise, compare by the taxonomy generation.
if (indexCommitGen < indexGen) {
return -1;
} else if (indexCommitGen > indexGen) {
return 1;
} else {
return taxoCommitGen < taxoGen ? -1 : (taxoCommitGen > taxoGen ? 1 : 0);
}
}
@Override
public int compareTo(Revision o) {
IndexAndTaxonomyRevision other = (IndexAndTaxonomyRevision) o;
int cmp = indexCommit.compareTo(other.indexCommit);
return cmp != 0 ? cmp : taxoCommit.compareTo(other.taxoCommit);
}
@Override
public String getVersion() {
return version;
}
@Override
public Map<String,List<RevisionFile>> getSourceFiles() {
return sourceFiles;
}
@Override
public InputStream open(String source, String fileName) throws IOException {
assert source.equals(INDEX_SOURCE) || source.equals(TAXONOMY_SOURCE) : "invalid source; expected=(" + INDEX_SOURCE
+ " or " + TAXONOMY_SOURCE + ") got=" + source;
IndexCommit ic = source.equals(INDEX_SOURCE) ? indexCommit : taxoCommit;
return new IndexInputInputStream(ic.getDirectory().openInput(fileName, IOContext.READONCE));
}
@Override
public void release() throws IOException {
try {
indexSDP.release(indexCommit);
} finally {
taxoSDP.release(taxoCommit);
}
try {
indexWriter.deleteUnusedFiles();
} finally {
taxoWriter.getIndexWriter().deleteUnusedFiles();
}
}
@Override
public String toString() {
return "IndexAndTaxonomyRevision version=" + version + " files=" + sourceFiles;
}
}