/*
* 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.rest.action;
import org.apache.logging.log4j.Logger;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.common.logging.Loggers;
import org.elasticsearch.rest.BytesRestResponse;
import org.elasticsearch.rest.RestChannel;
/**
* An action listener that requires {@link #processResponse(Object)} to be implemented
* and will automatically handle failures.
*/
public abstract class RestActionListener<Response> implements ActionListener<Response> {
// we use static here so we won't have to pass the actual logger each time for a very rare case of logging
// where the settings don't matter that much
private static Logger logger = Loggers.getLogger(RestResponseListener.class);
protected final RestChannel channel;
protected RestActionListener(RestChannel channel) {
this.channel = channel;
}
@Override
public final void onResponse(Response response) {
try {
processResponse(response);
} catch (Exception e) {
onFailure(e);
}
}
protected abstract void processResponse(Response response) throws Exception;
@Override
public final void onFailure(Exception e) {
try {
channel.sendResponse(new BytesRestResponse(channel, e));
} catch (Exception inner) {
inner.addSuppressed(e);
logger.error("failed to send failure response", inner);
}
}
}