java zookeeper 基本操作指令

怼烎@ 2021-12-15 06:57 302阅读 0赞

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 {
    	
    	    //超时时间
    	    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);
    	        			// 判断事件的类型是否是删除了，如果删除就之间返回程序
    	        			if (type == EventType.NodeDeleted) {
    	        				System.out.println(path + "节点被删除了，程序需停止" + type);
    	        				return;
    	        			}
    	        			if (type == EventType.NodeDataChanged) {
    	        				System.out.println(path + "节点内容有改动" + type);
    	        				return;
    	        			}
    	        			if (type == EventType.NodeCreated) {
    	        				System.out.println(path + "新建节点" + type);
    	        				return;
    	        			}
    	        			if (type == EventType.NodeChildrenChanged) {
    	        				System.out.println(path + "子节点有变动" + type);
    	        				return;
    	        			}
    	        			// 打印节点变动的信息
    	        			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);
    	            //获取zk列表
    	            //listNode(zk);
    	            //获取value
    	           // getData(zk);
    	            //删除 节点
    	           //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链接客户端的指令  
cd /zookeeper/bin  
sh [zKcli.sh][]  
新建  
create -s -e /test  
\-s:创建顺序节点  
\-e:创建临时节点  
获取子节点列表  
ls /test  
获取节点信息指令  
get /test  
修改指令  
set /test data  
删除指令  
delete /test

zookeeper权限控制  
在实际应用中，我们搭建一个zookeeper集群，统一为若干应用服务，如kafka集群，dubbo等，为了避免一个应用的数据被其它的应该干扰，我们需要权限控制。  
身份认证模式分为：world，auth，digest，ip  
world：默认方式，相当于全世界都能访问  
auth：代表已经认证通过的用户(cli中可以通过addauth digest user:pwd 来添加当前上下文中的授权用户)  
digest：即用户名:密码这种方式认证，这也是业务系统中最常用的  
ip：使用Ip地址认证

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));

此时zk1查询节点信息会报错 ：zookeeperException$NoAuthException

我们应该为zk1增加权限

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));

[zKcli.sh]: http://zKcli.sh