| /** |
| * 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 com.twitter.distributedlog.service.balancer; |
| |
| import com.twitter.distributedlog.client.monitor.MonitorServiceClient; |
| import com.twitter.distributedlog.service.DistributedLogClient; |
| import com.twitter.util.Await; |
| import com.twitter.util.Function; |
| import com.twitter.util.Future; |
| import com.twitter.util.FutureEventListener; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Move Streams from <i>src</i> to <i>target</i>. |
| */ |
| public class StreamMoverImpl implements StreamMover { |
| |
| private static final Logger logger = LoggerFactory.getLogger(StreamMoverImpl.class); |
| |
| final String source, target; |
| final DistributedLogClient srcClient, targetClient; |
| final MonitorServiceClient srcMonitor, targetMonitor; |
| |
| public StreamMoverImpl(String source, DistributedLogClient srcClient, MonitorServiceClient srcMonitor, |
| String target, DistributedLogClient targetClient, MonitorServiceClient targetMonitor) { |
| this.source = source; |
| this.srcClient = srcClient; |
| this.srcMonitor = srcMonitor; |
| this.target = target; |
| this.targetClient = targetClient; |
| this.targetMonitor = targetMonitor; |
| } |
| |
| /** |
| * Move given stream <i>streamName</i>. |
| * |
| * @param streamName |
| * stream name to move |
| * @return <i>true</i> if successfully moved the stream, <i>false</i> when failure happens. |
| * @throws Exception |
| */ |
| public boolean moveStream(final String streamName) { |
| try { |
| doMoveStream(streamName); |
| return true; |
| } catch (Exception e) { |
| return false; |
| } |
| } |
| |
| private void doMoveStream(final String streamName) throws Exception { |
| Await.result(srcClient.release(streamName).flatMap(new Function<Void, Future<Void>>() { |
| @Override |
| public Future<Void> apply(Void result) { |
| return targetMonitor.check(streamName).addEventListener(new FutureEventListener<Void>() { |
| @Override |
| public void onSuccess(Void value) { |
| logger.info("Moved stream {} from {} to {}.", |
| new Object[]{streamName, source, target}); |
| } |
| |
| @Override |
| public void onFailure(Throwable cause) { |
| logger.info("Failed to move stream {} from region {} to {} : ", |
| new Object[]{streamName, source, target, cause}); |
| } |
| }); |
| } |
| })); |
| } |
| |
| @Override |
| public String toString() { |
| StringBuilder sb = new StringBuilder(); |
| sb.append("StreamMover('").append(source).append("' -> '").append(target).append("')"); |
| return sb.toString(); |
| } |
| } |