Java tutorial
/** * 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.alibaba.jstorm.schedule; import java.io.File; import java.io.FileNotFoundException; import java.io.IOException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.UUID; import org.apache.commons.io.FileExistsException; import org.apache.commons.io.FileUtils; import org.apache.commons.lang.StringUtils; import org.apache.thrift.TException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.alibaba.jstorm.callback.RunnableCallback; import com.alibaba.jstorm.client.ConfigExtension; import com.alibaba.jstorm.cluster.Cluster; import com.alibaba.jstorm.cluster.StormClusterState; import com.alibaba.jstorm.cluster.StormConfig; import com.alibaba.jstorm.daemon.nimbus.NimbusData; import com.alibaba.jstorm.utils.JStormServerUtils; import com.alibaba.jstorm.utils.JStormUtils; import com.alibaba.jstorm.utils.NetWorkUtils; import com.alibaba.jstorm.utils.PathUtils; import backtype.storm.Config; import backtype.storm.utils.Utils; public class FollowerRunnable implements Runnable { private static final Logger LOG = LoggerFactory.getLogger(FollowerRunnable.class); private NimbusData data; private int sleepTime; private volatile boolean state = true; private RunnableCallback callback; private final String hostPort; public static final String NIMBUS_DIFFER_COUNT_ZK = "nimbus.differ.count.zk"; public static final Integer SLAVE_NIMBUS_WAIT_TIME = 120; @SuppressWarnings("unchecked") public FollowerRunnable(final NimbusData data, int sleepTime) { this.data = data; this.sleepTime = sleepTime; if (!ConfigExtension.isNimbusUseIp(data.getConf())) { this.hostPort = NetWorkUtils.hostname() + ":" + String.valueOf(Utils.getInt(data.getConf().get(Config.NIMBUS_THRIFT_PORT))); } else { this.hostPort = NetWorkUtils.ip() + ":" + String.valueOf(Utils.getInt(data.getConf().get(Config.NIMBUS_THRIFT_PORT))); } try { String[] hostfigs = this.hostPort.split(":"); boolean isLocaliP = false; if (hostfigs.length > 0) { isLocaliP = hostfigs[0].equals("127.0.0.1"); } if (isLocaliP) { throw new Exception("the hostname which Nimbus get is localhost"); } } catch (Exception e1) { LOG.error("get nimbus host error!", e1); throw new RuntimeException(e1); } try { data.getStormClusterState().update_nimbus_slave(hostPort, data.uptime()); data.getStormClusterState().update_nimbus_detail(hostPort, null); } catch (Exception e) { LOG.error("register nimbus host fail!", e); throw new RuntimeException(); } try { update_nimbus_detail(); } catch (Exception e) { LOG.error("register detail of nimbus fail!", e); throw new RuntimeException(); } try { this.tryToBeLeader(data.getConf()); } catch (Exception e1) { try { data.getStormClusterState().unregister_nimbus_host(hostPort); data.getStormClusterState().unregister_nimbus_detail(hostPort); } catch (Exception e2) { LOG.info("due to task errors, so remove register nimbus infomation"); } finally { // TODO Auto-generated catch block LOG.error("try to be leader error.", e1); throw new RuntimeException(e1); } } callback = new RunnableCallback() { @Override public void run() { if (!data.isLeader()) check(); } }; } public boolean isLeader(String zkMaster) { if (StringUtils.isBlank(zkMaster) == true) { return false; } if (hostPort.equalsIgnoreCase(zkMaster) == true) { return true; } // Two nimbus running on the same node isn't allowed // so just checks ip is enough here String[] part = zkMaster.split(":"); return NetWorkUtils.equals(part[0], NetWorkUtils.ip()); } @Override public void run() { // TODO Auto-generated method stub LOG.info("Follower Thread starts!"); while (state) { StormClusterState zkClusterState = data.getStormClusterState(); try { Thread.sleep(sleepTime); if (!zkClusterState.leader_existed()) { this.tryToBeLeader(data.getConf()); continue; } String master = zkClusterState.get_leader_host(); boolean isZkLeader = isLeader(master); if (data.isLeader() == true) { if (isZkLeader == false) { LOG.info("New ZK master is " + master); JStormUtils.halt_process(1, "Lose ZK master node, halt process"); return; } } if (isZkLeader == true) { zkClusterState.unregister_nimbus_host(hostPort); zkClusterState.unregister_nimbus_detail(hostPort); data.setLeader(true); continue; } check(); zkClusterState.update_nimbus_slave(hostPort, data.uptime()); update_nimbus_detail(); } catch (InterruptedException e) { // TODO Auto-generated catch block continue; } catch (Exception e) { if (state) { LOG.error("Unknow exception ", e); } } } LOG.info("Follower Thread has closed!"); } public void clean() { state = false; } private synchronized void check() { StormClusterState clusterState = data.getStormClusterState(); try { String master_stormdist_root = StormConfig.masterStormdistRoot(data.getConf()); List<String> code_ids = PathUtils.read_dir_contents(master_stormdist_root); List<String> assignments_ids = clusterState.assignments(callback); Map<String, Assignment> assignmentMap = new HashMap<String, Assignment>(); List<String> update_ids = new ArrayList<String>(); for (String id : assignments_ids) { Assignment assignment = clusterState.assignment_info(id, null); Long localCodeDownTS; try { Long tmp = StormConfig.read_nimbus_topology_timestamp(data.getConf(), id); localCodeDownTS = (tmp == null ? 0L : tmp); } catch (FileNotFoundException e) { localCodeDownTS = 0L; } if (assignment != null && assignment.isTopologyChange(localCodeDownTS.longValue())) { update_ids.add(id); } assignmentMap.put(id, assignment); } List<String> done_ids = new ArrayList<String>(); for (String id : code_ids) { if (assignments_ids.contains(id)) { done_ids.add(id); } } for (String id : done_ids) { assignments_ids.remove(id); code_ids.remove(id); } //redownload topologyid which hava been updated; assignments_ids.addAll(update_ids); for (String topologyId : code_ids) { deleteLocalTopology(topologyId); } for (String id : assignments_ids) { downloadCodeFromMaster(assignmentMap.get(id), id); } } catch (IOException e) { // TODO Auto-generated catch block LOG.error("Get stormdist dir error!", e); return; } catch (Exception e) { // TODO Auto-generated catch block LOG.error("Check error!", e); return; } } private void deleteLocalTopology(String topologyId) throws IOException { String dir_to_delete = StormConfig.masterStormdistRoot(data.getConf(), topologyId); try { PathUtils.rmr(dir_to_delete); LOG.info("delete:" + dir_to_delete + "successfully!"); } catch (IOException e) { // TODO Auto-generated catch block LOG.error("delete:" + dir_to_delete + "fail!", e); } } private void downloadCodeFromMaster(Assignment assignment, String topologyId) throws IOException, TException { try { String localRoot = StormConfig.masterStormdistRoot(data.getConf(), topologyId); String tmpDir = StormConfig.masterInbox(data.getConf()) + "/" + UUID.randomUUID().toString(); String masterCodeDir = assignment.getMasterCodeDir(); JStormServerUtils.downloadCodeFromMaster(data.getConf(), tmpDir, masterCodeDir, topologyId, false); File srcDir = new File(tmpDir); File destDir = new File(localRoot); try { FileUtils.moveDirectory(srcDir, destDir); } catch (FileExistsException e) { FileUtils.copyDirectory(srcDir, destDir); FileUtils.deleteQuietly(srcDir); } // Update downloadCode timeStamp StormConfig.write_nimbus_topology_timestamp(data.getConf(), topologyId, System.currentTimeMillis()); } catch (TException e) { // TODO Auto-generated catch block LOG.error(e + " downloadStormCode failed " + "topologyId:" + topologyId + "masterCodeDir:" + assignment.getMasterCodeDir()); throw e; } LOG.info("Finished downloading code for topology id " + topologyId + " from " + assignment.getMasterCodeDir()); } private void tryToBeLeader(final Map conf) throws Exception { boolean allowed = check_nimbus_priority(); if (allowed) { RunnableCallback masterCallback = new RunnableCallback() { @Override public void run() { try { tryToBeLeader(conf); } catch (Exception e) { LOG.error("To be master error", e); JStormUtils.halt_process(30, "Cant't to be master" + e.getMessage()); } } }; LOG.info("This nimbus can be leader"); data.getStormClusterState().try_to_be_leader(Cluster.MASTER_SUBTREE, hostPort, masterCallback); } else { LOG.info("This nimbus can't be leader"); } } /** * Compared with other nimbus ,get priority of this nimbus * * @throws Exception */ private boolean check_nimbus_priority() throws Exception { int gap = update_nimbus_detail(); if (gap == 0) { return true; } int left = SLAVE_NIMBUS_WAIT_TIME; while (left > 0) { LOG.info("After " + left + " seconds, nimbus will try to be Leader!"); Thread.sleep(10 * 1000); left -= 10; } StormClusterState zkClusterState = data.getStormClusterState(); List<String> followers = zkClusterState.list_dirs(Cluster.NIMBUS_SLAVE_DETAIL_SUBTREE, false); if (followers == null || followers.size() == 0) { return false; } for (String follower : followers) { if (follower != null && !follower.equals(hostPort)) { Map bMap = zkClusterState.get_nimbus_detail(follower, false); if (bMap != null) { Object object = bMap.get(NIMBUS_DIFFER_COUNT_ZK); if (object != null && (JStormUtils.parseInt(object)) < gap) { LOG.info("Current node can't be leader, due to {} has higher priority", follower); return false; } } } } return true; } private int update_nimbus_detail() throws Exception { //update count = count of zk's binary files - count of nimbus's binary files StormClusterState zkClusterState = data.getStormClusterState(); String master_stormdist_root = StormConfig.masterStormdistRoot(data.getConf()); List<String> code_ids = PathUtils.read_dir_contents(master_stormdist_root); List<String> assignments_ids = data.getStormClusterState().assignments(callback); assignments_ids.removeAll(code_ids); Map mtmp = zkClusterState.get_nimbus_detail(hostPort, false); if (mtmp == null) { mtmp = new HashMap(); } mtmp.put(NIMBUS_DIFFER_COUNT_ZK, assignments_ids.size()); zkClusterState.update_nimbus_detail(hostPort, mtmp); LOG.debug("update nimbus's detail " + mtmp); return assignments_ids.size(); } /** * Check whether current node is master or not * * @throws Exception */ private void checkOwnMaster() throws Exception { int retry_times = 10; StormClusterState zkClient = data.getStormClusterState(); for (int i = 0; i < retry_times; i++, JStormUtils.sleepMs(sleepTime)) { if (zkClient.leader_existed() == false) { continue; } String zkHost = zkClient.get_leader_host(); if (hostPort.equals(zkHost) == true) { // current process own master return; } LOG.warn("Current Nimbus has start thrift, but fail to own zk master :" + zkHost); } // current process doesn't own master String err = "Current Nimubs fail to own nimbus_master, should halt process"; LOG.error(err); JStormUtils.halt_process(0, err); } }