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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.search.aggregations.support;
import org.elasticsearch.common.ParseField;
import org.elasticsearch.common.ParsingException;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.query.QueryParseContext;
import org.elasticsearch.script.Script;
import org.elasticsearch.search.aggregations.AggregationBuilder.CommonFields;
import org.elasticsearch.search.aggregations.Aggregator;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public abstract class MultiValuesSourceParser<VS extends ValuesSource> implements Aggregator.Parser {
public abstract static class AnyValuesSourceParser extends MultiValuesSourceParser<ValuesSource> {
protected AnyValuesSourceParser(boolean formattable) {
super(formattable, ValuesSourceType.ANY, null);
}
}
public abstract static class NumericValuesSourceParser extends MultiValuesSourceParser<ValuesSource.Numeric> {
protected NumericValuesSourceParser(boolean formattable) {
super(formattable, ValuesSourceType.NUMERIC, ValueType.NUMERIC);
}
}
public abstract static class BytesValuesSourceParser extends MultiValuesSourceParser<ValuesSource.Bytes> {
protected BytesValuesSourceParser(boolean formattable) {
super(formattable, ValuesSourceType.BYTES, ValueType.STRING);
}
}
public abstract static class GeoPointValuesSourceParser extends MultiValuesSourceParser<ValuesSource.GeoPoint> {
protected GeoPointValuesSourceParser(boolean formattable) {
super(formattable, ValuesSourceType.GEOPOINT, ValueType.GEOPOINT);
}
}
private boolean formattable = false;
private ValuesSourceType valuesSourceType = null;
private ValueType targetValueType = null;
private MultiValuesSourceParser(boolean formattable, ValuesSourceType valuesSourceType, ValueType targetValueType) {
this.valuesSourceType = valuesSourceType;
this.targetValueType = targetValueType;
this.formattable = formattable;
}
@Override
public final MultiValuesSourceAggregationBuilder<VS, ?> parse(String aggregationName, QueryParseContext context)
throws IOException {
XContentParser parser = context.parser();
List<String> fields = null;
ValueType valueType = null;
String format = null;
Map<String, Object> missingMap = null;
Map<ParseField, Object> otherOptions = new HashMap<>();
XContentParser.Token token;
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.VALUE_STRING) {
if (CommonFields.FIELDS.match(currentFieldName)) {
fields = Collections.singletonList(parser.text());
} else if (formattable && CommonFields.FORMAT.match(currentFieldName)) {
format = parser.text();
} else if (CommonFields.VALUE_TYPE.match(currentFieldName)) {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "]. " +
"Multi-field aggregations do not support scripts.");
} else if (!token(aggregationName, currentFieldName, token, parser, otherOptions)) {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "].");
}
} else if (token == XContentParser.Token.START_OBJECT) {
if (CommonFields.MISSING.match(currentFieldName)) {
missingMap = new HashMap<>();
while (parser.nextToken() != XContentParser.Token.END_OBJECT) {
parseMissingAndAdd(aggregationName, currentFieldName, parser, missingMap);
}
} else if (Script.SCRIPT_PARSE_FIELD.match(currentFieldName)) {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "]. " +
"Multi-field aggregations do not support scripts.");
} else if (!token(aggregationName, currentFieldName, token, parser, otherOptions)) {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "].");
}
} else if (token == XContentParser.Token.START_ARRAY) {
if (Script.SCRIPT_PARSE_FIELD.match(currentFieldName)) {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "]. " +
"Multi-field aggregations do not support scripts.");
} else if (CommonFields.FIELDS.match(currentFieldName)) {
fields = new ArrayList<>();
while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
if (token == XContentParser.Token.VALUE_STRING) {
fields.add(parser.text());
} else {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "].");
}
}
} else if (!token(aggregationName, currentFieldName, token, parser, otherOptions)) {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "].");
}
} else if (!token(aggregationName, currentFieldName, token, parser, otherOptions)) {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "].");
}
}
MultiValuesSourceAggregationBuilder<VS, ?> factory = createFactory(aggregationName, this.valuesSourceType, this.targetValueType,
otherOptions);
if (fields != null) {
factory.fields(fields);
}
if (valueType != null) {
factory.valueType(valueType);
}
if (format != null) {
factory.format(format);
}
if (missingMap != null) {
factory.missingMap(missingMap);
}
return factory;
}
private void parseMissingAndAdd(final String aggregationName, final String currentFieldName,
XContentParser parser, final Map<String, Object> missing) throws IOException {
XContentParser.Token token = parser.currentToken();
if (token == null) {
token = parser.nextToken();
}
if (token == XContentParser.Token.FIELD_NAME) {
final String fieldName = parser.currentName();
if (missing.containsKey(fieldName)) {
throw new ParsingException(parser.getTokenLocation(),
"Missing field [" + fieldName + "] already defined as [" + missing.get(fieldName)
+ "] in [" + aggregationName + "].");
}
parser.nextToken();
missing.put(fieldName, parser.objectText());
} else {
throw new ParsingException(parser.getTokenLocation(),
"Unexpected token " + token + " [" + currentFieldName + "] in [" + aggregationName + "]");
}
}
/**
* Creates a {@link ValuesSourceAggregationBuilder} from the information
* gathered by the subclass. Options parsed in
* {@link MultiValuesSourceParser} itself will be added to the factory
* after it has been returned by this method.
*
* @param aggregationName
* the name of the aggregation
* @param valuesSourceType
* the type of the {@link ValuesSource}
* @param targetValueType
* the target type of the final value output by the aggregation
* @param otherOptions
* a {@link Map} containing the extra options parsed by the
* {@link #token(String, String, XContentParser.Token, XContentParser, Map)}
* method
* @return the created factory
*/
protected abstract MultiValuesSourceAggregationBuilder<VS, ?> createFactory(String aggregationName, ValuesSourceType valuesSourceType,
ValueType targetValueType, Map<ParseField, Object> otherOptions);
/**
* Allows subclasses of {@link MultiValuesSourceParser} to parse extra
* parameters and store them in a {@link Map} which will later be passed to
* {@link #createFactory(String, ValuesSourceType, ValueType, Map)}.
*
* @param aggregationName
* the name of the aggregation
* @param currentFieldName
* the name of the current field being parsed
* @param token
* the current token for the parser
* @param parser
* the parser
* @param otherOptions
* a {@link Map} of options to be populated by successive calls
* to this method which will then be passed to the
* {@link #createFactory(String, ValuesSourceType, ValueType, Map)}
* method
* @return <code>true</code> if the current token was correctly parsed,
* <code>false</code> otherwise
* @throws IOException
* if an error occurs whilst parsing
*/
protected abstract boolean token(String aggregationName, String currentFieldName, XContentParser.Token token, XContentParser parser,
Map<ParseField, Object> otherOptions) throws IOException;
}