/*
* Licensed to Elastic Search and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Elastic Search 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.query;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.Filter;
import org.elasticsearch.ElasticSearchIllegalStateException;
import org.elasticsearch.common.collect.Maps;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.lucene.docset.GetDocSet;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.cache.filter.support.CacheKeyFilter;
import org.elasticsearch.script.ScriptService;
import org.elasticsearch.script.SearchScript;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
import java.util.Map;
/**
* @author kimchy (shay.banon)
*/
public class ScriptFilterParser implements FilterParser {
public static final String NAME = "script";
@Inject public ScriptFilterParser() {
}
@Override public String[] names() {
return new String[]{NAME};
}
@Override public Filter parse(QueryParseContext parseContext) throws IOException, QueryParsingException {
XContentParser parser = parseContext.parser();
XContentParser.Token token;
boolean cache = false; // no need to cache it by default, changes a lot?
CacheKeyFilter.Key cacheKey = null;
// also, when caching, since its isCacheable is false, will result in loading all bit set...
String script = null;
String scriptLang = null;
Map<String, Object> params = null;
String filterName = null;
String currentFieldName = null;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token == XContentParser.Token.START_OBJECT) {
if ("params".equals(currentFieldName)) {
params = parser.map();
}
} else if (token.isValue()) {
if ("script".equals(currentFieldName)) {
script = parser.text();
} else if ("lang".equals(currentFieldName)) {
scriptLang = parser.text();
} else if ("_name".equals(currentFieldName)) {
filterName = parser.text();
} else if ("_cache".equals(currentFieldName)) {
cache = parser.booleanValue();
} else if ("_cache_key".equals(currentFieldName) || "_cacheKey".equals(currentFieldName)) {
cacheKey = new CacheKeyFilter.Key(parser.text());
}
}
}
if (script == null) {
throw new QueryParsingException(parseContext.index(), "script must be provided with a [script] filter");
}
if (params == null) {
params = Maps.newHashMap();
}
Filter filter = new ScriptFilter(scriptLang, script, params, parseContext.scriptService());
if (cache) {
filter = parseContext.cacheFilter(filter, cacheKey);
}
if (filterName != null) {
parseContext.addNamedFilter(filterName, filter);
}
return filter;
}
public static class ScriptFilter extends Filter {
private final String script;
private final Map<String, Object> params;
private final SearchScript searchScript;
private ScriptFilter(String scriptLang, String script, Map<String, Object> params, ScriptService scriptService) {
this.script = script;
this.params = params;
SearchContext context = SearchContext.current();
if (context == null) {
throw new ElasticSearchIllegalStateException("No search context on going...");
}
this.searchScript = context.scriptService().search(context.lookup(), scriptLang, script, params);
}
@Override public String toString() {
StringBuilder buffer = new StringBuilder();
buffer.append("ScriptFilter(");
buffer.append(script);
buffer.append(")");
return buffer.toString();
}
@Override public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
ScriptFilter that = (ScriptFilter) o;
if (params != null ? !params.equals(that.params) : that.params != null) return false;
if (script != null ? !script.equals(that.script) : that.script != null) return false;
return true;
}
@Override public int hashCode() {
int result = script != null ? script.hashCode() : 0;
result = 31 * result + (params != null ? params.hashCode() : 0);
return result;
}
@Override public DocIdSet getDocIdSet(final IndexReader reader) throws IOException {
searchScript.setNextReader(reader);
return new ScriptDocSet(reader, searchScript);
}
static class ScriptDocSet extends GetDocSet {
private final SearchScript searchScript;
public ScriptDocSet(IndexReader reader, SearchScript searchScript) {
super(reader.maxDoc());
this.searchScript = searchScript;
}
@Override public long sizeInBytes() {
return 0;
}
@Override public boolean isCacheable() {
// not cacheable for several reasons:
// 1. The script service is shared and holds the current reader executing against, and it
// gets changed on each getDocIdSet (which is fine for sequential reader search)
// 2. If its really going to be cached (the _cache setting), its better to just load it into in memory bitset
return false;
}
@Override public boolean get(int doc) throws IOException {
searchScript.setNextDocId(doc);
Object val = searchScript.run();
if (val == null) {
return false;
}
if (val instanceof Boolean) {
return (Boolean) val;
}
if (val instanceof Number) {
return ((Number) val).longValue() != 0;
}
throw new IOException("Can't handle type [" + val + "] in script filter");
}
}
}
}