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* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.index.aliases;
import org.apache.lucene.queries.FilterClause;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.Filter;
import org.elasticsearch.common.Nullable;
import org.elasticsearch.common.compress.CompressedString;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.lucene.search.XBooleanFilter;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
import org.elasticsearch.common.xcontent.XContentFactory;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.AbstractIndexComponent;
import org.elasticsearch.index.Index;
import org.elasticsearch.index.query.IndexQueryParserService;
import org.elasticsearch.index.query.ParsedFilter;
import org.elasticsearch.index.settings.IndexSettings;
import org.elasticsearch.indices.AliasFilterParsingException;
import org.elasticsearch.indices.InvalidAliasNameException;
import java.io.IOException;
import java.util.Iterator;
import java.util.Map;
/**
*
*/
public class IndexAliasesService extends AbstractIndexComponent implements Iterable<IndexAlias> {
private final IndexQueryParserService indexQueryParser;
private final Map<String, IndexAlias> aliases = ConcurrentCollections.newConcurrentMapWithAggressiveConcurrency();
@Inject
public IndexAliasesService(Index index, @IndexSettings Settings indexSettings, IndexQueryParserService indexQueryParser) {
super(index, indexSettings);
this.indexQueryParser = indexQueryParser;
}
public boolean hasAlias(String alias) {
return aliases.containsKey(alias);
}
public IndexAlias alias(String alias) {
return aliases.get(alias);
}
public IndexAlias create(String alias, @Nullable CompressedString filter) {
return new IndexAlias(alias, filter, parse(alias, filter));
}
public void add(String alias, @Nullable CompressedString filter) {
add(new IndexAlias(alias, filter, parse(alias, filter)));
}
public void addAll(Map<String, IndexAlias> aliases) {
this.aliases.putAll(aliases);
}
/**
* Returns the filter associated with listed filtering aliases.
* <p/>
* <p>The list of filtering aliases should be obtained by calling MetaData.filteringAliases.
* Returns <tt>null</tt> if no filtering is required.</p>
*/
public Filter aliasFilter(String... aliases) {
if (aliases == null || aliases.length == 0) {
return null;
}
if (aliases.length == 1) {
IndexAlias indexAlias = alias(aliases[0]);
if (indexAlias == null) {
// This shouldn't happen unless alias disappeared after filteringAliases was called.
throw new InvalidAliasNameException(index, aliases[0], "Unknown alias name was passed to alias Filter");
}
return indexAlias.parsedFilter();
} else {
// we need to bench here a bit, to see maybe it makes sense to use OrFilter
XBooleanFilter combined = new XBooleanFilter();
for (String alias : aliases) {
IndexAlias indexAlias = alias(alias);
if (indexAlias == null) {
// This shouldn't happen unless alias disappeared after filteringAliases was called.
throw new InvalidAliasNameException(index, aliases[0], "Unknown alias name was passed to alias Filter");
}
if (indexAlias.parsedFilter() != null) {
combined.add(new FilterClause(indexAlias.parsedFilter(), BooleanClause.Occur.SHOULD));
} else {
// The filter might be null only if filter was removed after filteringAliases was called
return null;
}
}
if (combined.clauses().size() == 0) {
return null;
}
if (combined.clauses().size() == 1) {
return combined.clauses().get(0).getFilter();
}
return combined;
}
}
private void add(IndexAlias indexAlias) {
aliases.put(indexAlias.alias(), indexAlias);
}
public void remove(String alias) {
aliases.remove(alias);
}
private Filter parse(String alias, CompressedString filter) {
if (filter == null) {
return null;
}
try {
byte[] filterSource = filter.uncompressed();
try (XContentParser parser = XContentFactory.xContent(filterSource).createParser(filterSource)) {
ParsedFilter parsedFilter = indexQueryParser.parseInnerFilter(parser);
return parsedFilter == null ? null : parsedFilter.filter();
}
} catch (IOException ex) {
throw new AliasFilterParsingException(index, alias, "Invalid alias filter", ex);
}
}
@Override
public Iterator<IndexAlias> iterator() {
return aliases.values().iterator();
}
}