RestFilter.java

/*
 * Licensed to ElasticSearch and Shay Banon 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.rest;

import org.elasticsearch.ElasticSearchException;
import org.elasticsearch.common.component.CloseableComponent;

/**
 * A filter allowing to filter rest operations.
 */
public abstract class RestFilter implements CloseableComponent {

    /**
     * Optionally, the order of the filter. Execution is done from lowest value to highest.
     * It is a good practice to allow to configure this for the relevant filter.
     */
    public int order() {
        return 0;
    }

    @Override
    public void close() throws ElasticSearchException {
        // a no op
    }

    /**
     * Process the rest request. Using the channel to send a response, or the filter chain to continue
     * processing the request.
     */
    public abstract void process(RestRequest request, RestChannel channel, RestFilterChain filterChain);
}