/*
* 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.
*/
package org.apache.nifi.record.path.paths;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.stream.Stream;
import org.apache.nifi.record.path.FieldValue;
import org.apache.nifi.record.path.RecordPathEvaluationContext;
import org.apache.nifi.record.path.StandardFieldValue;
import org.apache.nifi.record.path.util.Filters;
import org.apache.nifi.serialization.record.Record;
import org.apache.nifi.serialization.record.RecordField;
public class DescendantFieldPath extends RecordPathSegment {
private final String descendantName;
DescendantFieldPath(final String descendantName, final RecordPathSegment parent, final boolean absolute) {
super("//" + descendantName, parent, absolute);
this.descendantName = descendantName;
}
@Override
public Stream<FieldValue> evaluate(final RecordPathEvaluationContext context) {
final Stream<FieldValue> parentResult = getParentPath().evaluate(context);
return parentResult
.flatMap(recordFieldVal -> findDescendants(recordFieldVal).stream());
}
private List<FieldValue> findDescendants(final FieldValue fieldValue) {
if (fieldValue == null || fieldValue.getValue() == null) {
return Collections.emptyList();
}
if (!Filters.isRecord(fieldValue)) {
return Collections.emptyList();
}
final Record record = (Record) fieldValue.getValue();
final List<FieldValue> matchingValues = new ArrayList<>();
for (final RecordField childField : record.getSchema().getFields()) {
if (childField.getFieldName().equals(descendantName) || childField.getAliases().contains(descendantName)) {
final Object value = record.getValue(descendantName);
if (value != null) {
final FieldValue descendantFieldValue = new StandardFieldValue(value, childField, fieldValue);
matchingValues.add(descendantFieldValue);
}
}
final Object recordValue = record.getValue(childField.getFieldName());
if (recordValue == null) {
continue;
}
if (Filters.isRecord(childField.getDataType(), recordValue)) {
final FieldValue childFieldValue = new StandardFieldValue(recordValue, childField, fieldValue);
matchingValues.addAll(findDescendants(childFieldValue));
}
}
return matchingValues;
}
}