java zookeeper 基本操作指令

package zookeeper;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event.EventType;
import org.apache.zookeeper.data.Stat;
import java.util.List;
import java.util.concurrent.CountDownLatch;
	
	/**
	 *
	 */
	public class CreateZNode {
	
	    //逾時時間
	    private static final int SESSION_TIMEOUT = 500000;
	    private  CountDownLatch connectedSignal = new CountDownLatch(1);
	    public static WatchTest watch = new WatchTest();

	    public static void main(String[] args) {
	        try {
	            Watcher wh = new Watcher() {
	            	public void process(WatchedEvent event) {
	            		String path = event.getPath();
	            		EventType type = event.getType();
	            		System.out.println("----------int---"+type.getIntValue());
	            		System.out.println("----------path---"+path);
	            		System.out.println("----------type---"+type);
	        			// 判斷事件的類型是否是删除了，如果删除就之間傳回程式
	        			if (type == EventType.NodeDeleted) {
	        				System.out.println(path + "節點被删除了，程式需停止" + type);
	        				return;
	        			}
	        			if (type == EventType.NodeDataChanged) {
	        				System.out.println(path + "節點内容有改動" + type);
	        				return;
	        			}
	        			if (type == EventType.NodeCreated) {
	        				System.out.println(path + "建立節點" + type);
	        				return;
	        			}
	        			if (type == EventType.NodeChildrenChanged) {
	        				System.out.println(path + "子節點有變動" + type);
	        				return;
	        			}
	        			// 列印節點變動的資訊
	        			System.out.println(path + "出事了" + type);
	            		
	            	}
	            };
            
	            ZooKeeper zk = new ZooKeeper("127.0.0.1:2181", SESSION_TIMEOUT, wh);
	            createNode(zk);
	            //修改
	            //updateNode(zk);
	            //擷取zk清單
	            //listNode(zk);
	            //擷取value
	           // getData(zk);
	            //删除 節點
	           //deleteNode(zk);
	           
	        } catch (Exception e) {
	            e.printStackTrace();
	        }
	    }

	    private static void updateNode(ZooKeeper zk) throws Exception {
			Stat update = zk.setData("/axz/b", "4545346".getBytes(), -1);
			System.out.println(update);
		}

		private static void deleteNode(ZooKeeper zk) throws Exception {
			// TODO Auto-generated method stub
			zk.delete("/zxz/c", -1);
		}

		private static void listNode(ZooKeeper zk) throws KeeperException, InterruptedException {
	    	List<String> idList = zk.getChildren("/zxz/b", false);
            idList.forEach(s->{
            	System.out.println(s);
            });
		}

		private static void getData(ZooKeeper zk) throws Exception {
			byte[] bytes = zk.getData("/zxz/b", false, new Stat());
			System.out.println(new String(bytes));
		}

		public static void createNode(ZooKeeper zk) throws Exception {
	    	 String str1 = zk.create("/axz", "abc".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
	    }
}
           

linux連結用戶端的指令

cd /zookeeper/bin

sh zKcli.sh

建立

create -s -e /test

-s:建立順序節點

-e:建立臨時節點

擷取子節點清單

ls /test

擷取節點資訊指令

get /test

修改指令

set /test data

删除指令

delete /test

zookeeper權限控制

在實際應用中，我們搭建一個zookeeper叢集，統一為若幹應用服務，如kafka叢集，dubbo等，為了避免一個應用的資料被其它的應該幹擾，我們需要權限控制。

身份認證模式分為：world，auth，digest，ip

world：預設方式，相當于全世界都能通路

auth：代表已經認證通過的使用者(cli中可以通過addauth digest user:pwd 來添加目前上下文中的授權使用者)

digest：即使用者名:密碼這種方式認證，這也是業務系統中最常用的

ip：使用Ip位址認證

ZooKeeper zk = new ZooKeeper("127.0.0.1:2181", SESSION_TIMEOUT, null);
zk.addAuthInfo("digest","foo:true".getBytes());
zk.create("/fff", "123".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
ZooKeeper zk1 = new ZooKeeper("127.0.0.1:2181", SESSION_TIMEOUT, null);
byte[] bytes = zk1.getData("/fff", false, new Stat());
System.out.println(new String(bytes));
           

此時zk1查詢節點資訊會報錯 ：zookeeperException$NoAuthException

我們應該為zk1增權重限

ZooKeeper zk1 = new ZooKeeper("127.0.0.1:2181", SESSION_TIMEOUT, null);
zk1.addAuthInfo("digest","foo:true".getBytes());
byte[] bytes = zk1.getData("/fff", false, new Stat());
System.out.println(new String(bytes));