/*
* 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.attribute.expression.language.evaluation.functions;
import java.io.UnsupportedEncodingException;
import java.util.Base64;
import java.util.Map;
import org.apache.nifi.attribute.expression.language.evaluation.Evaluator;
import org.apache.nifi.attribute.expression.language.evaluation.QueryResult;
import org.apache.nifi.attribute.expression.language.evaluation.StringEvaluator;
import org.apache.nifi.attribute.expression.language.evaluation.StringQueryResult;
public class Base64DecodeEvaluator extends StringEvaluator {
private final Evaluator<String> subject;
public Base64DecodeEvaluator(final Evaluator<String> subject) {
this.subject = subject;
}
@Override
public QueryResult<String> evaluate(final Map<String, String> attributes) {
final String subjectValue = subject.evaluate(attributes).getValue();
if (subjectValue == null) {
return new StringQueryResult(null);
}
try {
return new StringQueryResult(new String(Base64.getDecoder().decode(subjectValue), "UTF-8"));
} catch (final UnsupportedEncodingException e) {
return null; // won't happen. It's UTF-8
}
}
@Override
public Evaluator<?> getSubjectEvaluator() {
return subject;
}
}