/*
 * 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.camel.component.kafka;

import java.util.regex.Pattern;

import org.apache.camel.support.DefaultHeaderFilterStrategy;

public class KafkaHeaderFilterStrategy extends DefaultHeaderFilterStrategy {

    /**
     * A filter pattern that only accepts keys starting with <tt>Camel</tt> or <tt>org.apache.camel.</tt>
     */
    public static final Pattern CAMEL_KAFKA_FILTER_PATTERN
            = Pattern.compile("(?i)(Camel|org\\.apache\\.camel|kafka\\.)[\\.|a-z|A-Z|0-9]*");

    public KafkaHeaderFilterStrategy() {
        initialize();
    }

    protected void initialize() {
        // filter out kafka record metadata
        getInFilter().add("org.apache.kafka.clients.producer.RecordMetadata");

        // filter headers beginning with "Camel" or "org.apache.camel" or "kafka."
        setOutFilterPattern(CAMEL_KAFKA_FILTER_PATTERN);
        setInFilterPattern(CAMEL_KAFKA_FILTER_PATTERN);
    }
}
