| package org.apache.solr.common.cloud; |
| |
| /* |
| * 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. |
| */ |
| |
| import java.util.concurrent.CountDownLatch; |
| import java.util.concurrent.TimeoutException; |
| |
| import org.apache.solr.common.SolrException; |
| import org.apache.zookeeper.WatchedEvent; |
| import org.apache.zookeeper.Watcher; |
| import org.apache.zookeeper.Watcher.Event.KeeperState; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| class ConnectionManager implements Watcher { |
| protected static final Logger log = LoggerFactory |
| .getLogger(ConnectionManager.class); |
| |
| private final String name; |
| private CountDownLatch clientConnected; |
| private KeeperState state; |
| private boolean connected; |
| |
| private final ZkClientConnectionStrategy connectionStrategy; |
| |
| private Object connectionUpdateLock = new Object(); |
| |
| private String zkServerAddress; |
| |
| private int zkClientTimeout; |
| |
| private SolrZkClient client; |
| |
| private OnReconnect onReconnect; |
| |
| private volatile boolean isClosed = false; |
| |
| public ConnectionManager(String name, SolrZkClient client, String zkServerAddress, int zkClientTimeout, ZkClientConnectionStrategy strat, OnReconnect onConnect) { |
| this.name = name; |
| this.client = client; |
| this.connectionStrategy = strat; |
| this.zkServerAddress = zkServerAddress; |
| this.zkClientTimeout = zkClientTimeout; |
| this.onReconnect = onConnect; |
| reset(); |
| } |
| |
| private synchronized void reset() { |
| clientConnected = new CountDownLatch(1); |
| state = KeeperState.Disconnected; |
| connected = false; |
| } |
| |
| @Override |
| public synchronized void process(WatchedEvent event) { |
| if (log.isInfoEnabled()) { |
| log.info("Watcher " + this + " name:" + name + " got event " + event |
| + " path:" + event.getPath() + " type:" + event.getType()); |
| } |
| |
| if (isClosed) { |
| log.info("Client->ZooKeeper status change trigger but we are already closed"); |
| return; |
| } |
| |
| state = event.getState(); |
| if (state == KeeperState.SyncConnected) { |
| connected = true; |
| clientConnected.countDown(); |
| connectionStrategy.connected(); |
| } else if (state == KeeperState.Expired) { |
| connected = false; |
| log.info("Our previous ZooKeeper session was expired. Attempting to reconnect to recover relationship with ZooKeeper..."); |
| |
| try { |
| connectionStrategy.reconnect(zkServerAddress, zkClientTimeout, this, |
| new ZkClientConnectionStrategy.ZkUpdate() { |
| @Override |
| public void update(SolrZooKeeper keeper) { |
| // if keeper does not replace oldKeeper we must be sure to close it |
| synchronized (connectionUpdateLock) { |
| try { |
| waitForConnected(SolrZkClient.DEFAULT_CLIENT_CONNECT_TIMEOUT); |
| } catch (Exception e1) { |
| closeKeeper(keeper); |
| throw new RuntimeException(e1); |
| } |
| log.info("Connection with ZooKeeper reestablished."); |
| try { |
| client.updateKeeper(keeper); |
| } catch (InterruptedException e) { |
| closeKeeper(keeper); |
| Thread.currentThread().interrupt(); |
| // we must have been asked to stop |
| throw new RuntimeException(e); |
| } catch(Throwable t) { |
| closeKeeper(keeper); |
| throw new RuntimeException(t); |
| } |
| |
| if (onReconnect != null) { |
| onReconnect.command(); |
| } |
| synchronized (ConnectionManager.this) { |
| ConnectionManager.this.connected = true; |
| } |
| } |
| |
| } |
| |
| }); |
| } catch (Exception e) { |
| SolrException.log(log, "", e); |
| } |
| log.info("Connected:" + connected); |
| } else if (state == KeeperState.Disconnected) { |
| log.info("zkClient has disconnected"); |
| connected = false; |
| connectionStrategy.disconnected(); |
| } else { |
| connected = false; |
| } |
| notifyAll(); |
| } |
| |
| public synchronized boolean isConnected() { |
| return !isClosed && connected; |
| } |
| |
| // we use a volatile rather than sync |
| // to avoid deadlock on shutdown |
| public void close() { |
| this.isClosed = true; |
| } |
| |
| public synchronized KeeperState state() { |
| return state; |
| } |
| |
| public synchronized void waitForConnected(long waitForConnection) |
| throws TimeoutException { |
| log.info("Waiting for client to connect to ZooKeeper"); |
| long expire = System.currentTimeMillis() + waitForConnection; |
| long left = 1; |
| while (!connected && left > 0) { |
| if (isClosed) { |
| break; |
| } |
| try { |
| wait(500); |
| } catch (InterruptedException e) { |
| Thread.currentThread().interrupt(); |
| throw new RuntimeException(e); |
| } |
| left = expire - System.currentTimeMillis(); |
| } |
| if (!connected) { |
| throw new TimeoutException("Could not connect to ZooKeeper " + zkServerAddress + " within " + waitForConnection + " ms"); |
| } |
| log.info("Client is connected to ZooKeeper"); |
| } |
| |
| public synchronized void waitForDisconnected(long timeout) |
| throws InterruptedException, TimeoutException { |
| long expire = System.currentTimeMillis() + timeout; |
| long left = timeout; |
| while (connected && left > 0) { |
| wait(left); |
| left = expire - System.currentTimeMillis(); |
| } |
| if (connected) { |
| throw new TimeoutException("Did not disconnect"); |
| } |
| } |
| |
| private void closeKeeper(SolrZooKeeper keeper) { |
| try { |
| keeper.close(); |
| } catch (InterruptedException e) { |
| // Restore the interrupted status |
| Thread.currentThread().interrupt(); |
| log.error("", e); |
| throw new ZooKeeperException(SolrException.ErrorCode.SERVER_ERROR, |
| "", e); |
| } |
| } |
| } |