/*
* 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.mapper;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.tokenattributes.PositionIncrementAttribute;
import org.apache.lucene.index.IndexOptions;
import org.apache.lucene.index.IndexableField;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.index.analysis.NamedAnalyzer;
import java.io.IOException;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import static org.elasticsearch.common.xcontent.support.XContentMapValues.nodeIntegerValue;
import static org.elasticsearch.common.xcontent.support.XContentMapValues.nodeBooleanValue;
import static org.elasticsearch.index.mapper.TypeParsers.parseField;
/**
* A {@link FieldMapper} that takes a string and writes a count of the tokens in that string
* to the index. In most ways the mapper acts just like an {@link NumberFieldMapper}.
*/
public class TokenCountFieldMapper extends FieldMapper {
public static final String CONTENT_TYPE = "token_count";
public static class Defaults {
public static final MappedFieldType FIELD_TYPE = new NumberFieldMapper.NumberFieldType(NumberFieldMapper.NumberType.INTEGER);
public static final boolean DEFAULT_POSITION_INCREMENTS = true;
}
public static class Builder extends FieldMapper.Builder<Builder, TokenCountFieldMapper> {
private NamedAnalyzer analyzer;
private boolean enablePositionIncrements = Defaults.DEFAULT_POSITION_INCREMENTS;
public Builder(String name) {
super(name, Defaults.FIELD_TYPE, Defaults.FIELD_TYPE);
builder = this;
}
public Builder analyzer(NamedAnalyzer analyzer) {
this.analyzer = analyzer;
return this;
}
public NamedAnalyzer analyzer() {
return analyzer;
}
public Builder enablePositionIncrements(boolean enablePositionIncrements) {
this.enablePositionIncrements = enablePositionIncrements;
return this;
}
public boolean enablePositionIncrements() {
return enablePositionIncrements;
}
@Override
public TokenCountFieldMapper build(BuilderContext context) {
setupFieldType(context);
return new TokenCountFieldMapper(name, fieldType, defaultFieldType,
context.indexSettings(), analyzer, enablePositionIncrements, multiFieldsBuilder.build(this, context), copyTo);
}
}
public static class TypeParser implements Mapper.TypeParser {
@Override
public Mapper.Builder<?,?> parse(String name, Map<String, Object> node, ParserContext parserContext) throws MapperParsingException {
TokenCountFieldMapper.Builder builder = new TokenCountFieldMapper.Builder(name);
for (Iterator<Map.Entry<String, Object>> iterator = node.entrySet().iterator(); iterator.hasNext();) {
Map.Entry<String, Object> entry = iterator.next();
String propName = entry.getKey();
Object propNode = entry.getValue();
if (propName.equals("null_value")) {
builder.nullValue(nodeIntegerValue(propNode));
iterator.remove();
} else if (propName.equals("analyzer")) {
NamedAnalyzer analyzer = parserContext.getIndexAnalyzers().get(propNode.toString());
if (analyzer == null) {
throw new MapperParsingException("Analyzer [" + propNode.toString() + "] not found for field [" + name + "]");
}
builder.analyzer(analyzer);
iterator.remove();
} else if (propName.equals("enable_position_increments")) {
builder.enablePositionIncrements(nodeBooleanValue(propNode));
iterator.remove();
}
}
parseField(builder, name, node, parserContext);
if (builder.analyzer() == null) {
throw new MapperParsingException("Analyzer must be set for field [" + name + "] but wasn't.");
}
return builder;
}
}
private NamedAnalyzer analyzer;
private boolean enablePositionIncrements;
protected TokenCountFieldMapper(String simpleName, MappedFieldType fieldType, MappedFieldType defaultFieldType,
Settings indexSettings, NamedAnalyzer analyzer, boolean enablePositionIncrements, MultiFields multiFields, CopyTo copyTo) {
super(simpleName, fieldType, defaultFieldType, indexSettings, multiFields, copyTo);
this.analyzer = analyzer;
this.enablePositionIncrements = enablePositionIncrements;
}
@Override
protected void parseCreateField(ParseContext context, List<IndexableField> fields) throws IOException {
final String value;
if (context.externalValueSet()) {
value = context.externalValue().toString();
} else {
value = context.parser().textOrNull();
}
final int tokenCount;
if (value == null) {
tokenCount = (Integer) fieldType().nullValue();
} else {
tokenCount = countPositions(analyzer, name(), value, enablePositionIncrements);
}
boolean indexed = fieldType().indexOptions() != IndexOptions.NONE;
boolean docValued = fieldType().hasDocValues();
boolean stored = fieldType().stored();
fields.addAll(NumberFieldMapper.NumberType.INTEGER.createFields(fieldType().name(), tokenCount, indexed, docValued, stored));
}
/**
* Count position increments in a token stream. Package private for testing.
* @param analyzer analyzer to create token stream
* @param fieldName field name to pass to analyzer
* @param fieldValue field value to pass to analyzer
* @param enablePositionIncrements should we count position increments ?
* @return number of position increments in a token stream
* @throws IOException if tokenStream throws it
*/
static int countPositions(Analyzer analyzer, String fieldName, String fieldValue, boolean enablePositionIncrements) throws IOException {
try (TokenStream tokenStream = analyzer.tokenStream(fieldName, fieldValue)) {
int count = 0;
PositionIncrementAttribute position = tokenStream.addAttribute(PositionIncrementAttribute.class);
tokenStream.reset();
while (tokenStream.incrementToken()) {
if (enablePositionIncrements) {
count += position.getPositionIncrement();
} else {
count += Math.min(1, position.getPositionIncrement());
}
}
tokenStream.end();
if (enablePositionIncrements) {
count += position.getPositionIncrement();
}
return count;
}
}
/**
* Name of analyzer.
* @return name of analyzer
*/
public String analyzer() {
return analyzer.name();
}
/**
* Indicates if position increments are counted.
* @return <code>true</code> if position increments are counted
*/
public boolean enablePositionIncrements() {
return enablePositionIncrements;
}
@Override
protected String contentType() {
return CONTENT_TYPE;
}
@Override
protected void doMerge(Mapper mergeWith, boolean updateAllTypes) {
super.doMerge(mergeWith, updateAllTypes);
this.analyzer = ((TokenCountFieldMapper) mergeWith).analyzer;
this.enablePositionIncrements = ((TokenCountFieldMapper) mergeWith).enablePositionIncrements;
}
@Override
protected void doXContentBody(XContentBuilder builder, boolean includeDefaults, Params params) throws IOException {
super.doXContentBody(builder, includeDefaults, params);
builder.field("analyzer", analyzer());
if (includeDefaults || enablePositionIncrements() != Defaults.DEFAULT_POSITION_INCREMENTS) {
builder.field("enable_position_increments", enablePositionIncrements());
}
}
}