ZooKeeper客户端 zkCli.sh 节点的增删改查

时间 2019-11-10

标签 zookeeper 客户端 zkcli.sh zkcli 节点增删栏目 Zookeeper 繁體版

原文原文链接

zkCli.sh

在 bin 目录下的 zkCli.sh 就是ZooKeeper客户端java

./zkCli.sh -timeout 5000 -server 127.0.0.1:2181 　　客户端与ZooKeeper创建连接node

timeout：超时时间，单位毫秒数据库

r：只读模式，当节点坏掉的时候，还能够提供读服务apache

示例：api

./zkCli.sh -timeout 5000 -server 127.0.0.1:2181session

 1 zhangliuningdeMacBook-Pro:bin sherry$ ./zkCli.sh -timeout 5000 -server 127.0.0.1:2181
 2 Connecting to 127.0.0.1:2181
 3 2016-08-27 15:07:04,036 [myid:] - INFO  [main:Environment@100] - Client environment:zookeeper.version=3.4.8--1, built on 02/06/2016 03:18 GMT
 4 2016-08-27 15:07:04,039 [myid:] - INFO  [main:Environment@100] - Client environment:host.name=192.168.0.105
 5 2016-08-27 15:07:04,039 [myid:] - INFO  [main:Environment@100] - Client environment:java.version=1.8.0_71
 6 2016-08-27 15:07:04,041 [myid:] - INFO  [main:Environment@100] - Client environment:java.vendor=Oracle Corporation
 7 2016-08-27 15:07:04,041 [myid:] - INFO  [main:Environment@100] - Client environment:java.home=/Library/Java/JavaVirtualMachines/jdk1.8.0_71.jdk/Contents/Home/jre
 8 2016-08-27 15:07:04,042 [myid:] - INFO  [main:Environment@100] - Client environment:java.class.path=/Users/sherry/Applications/zk1/bin/../build/classes:/Users/sherry/Applications/zk1/bin/../build/lib/*.jar:/Users/sherry/Applications/zk1/bin/../lib/slf4j-log4j12-1.6.1.jar:/Users/sherry/Applications/zk1/bin/../lib/slf4j-api-1.6.1.jar:/Users/sherry/Applications/zk1/bin/../lib/netty-3.7.0.Final.jar:/Users/sherry/Applications/zk1/bin/../lib/log4j-1.2.16.jar:/Users/sherry/Applications/zk1/bin/../lib/jline-0.9.94.jar:/Users/sherry/Applications/zk1/bin/../zookeeper-3.4.8.jar:/Users/sherry/Applications/zk1/bin/../src/java/lib/*.jar:/Users/sherry/Applications/zk1/bin/../conf:
 9 2016-08-27 15:07:04,042 [myid:] - INFO  [main:Environment@100] - Client environment:java.library.path=/Users/sherry/Library/Java/Extensions:/Library/Java/Extensions:/Network/Library/Java/Extensions:/System/Library/Java/Extensions:/usr/lib/java:.
10 2016-08-27 15:07:04,042 [myid:] - INFO  [main:Environment@100] - Client environment:java.io.tmpdir=/var/folders/_n/d05bph5x5bl6k5p0pkx2g66m0000gn/T/
11 2016-08-27 15:07:04,042 [myid:] - INFO  [main:Environment@100] - Client environment:java.compiler=<NA>
12 2016-08-27 15:07:04,042 [myid:] - INFO  [main:Environment@100] - Client environment:os.name=Mac OS X
13 2016-08-27 15:07:04,042 [myid:] - INFO  [main:Environment@100] - Client environment:os.arch=x86_64
14 2016-08-27 15:07:04,042 [myid:] - INFO  [main:Environment@100] - Client environment:os.version=10.11.5
15 2016-08-27 15:07:04,043 [myid:] - INFO  [main:Environment@100] - Client environment:user.name=sherry
16 2016-08-27 15:07:04,043 [myid:] - INFO  [main:Environment@100] - Client environment:user.home=/Users/sherry
17 2016-08-27 15:07:04,043 [myid:] - INFO  [main:Environment@100] - Client environment:user.dir=/Users/sherry/Applications/zk1/bin
18 2016-08-27 15:07:04,044 [myid:] - INFO  [main:ZooKeeper@438] - Initiating client connection, connectString=127.0.0.1:2181 sessionTimeout=5000 watcher=org.apache.zookeeper.ZooKeeperMain$MyWatcher@531d72ca
19 Welcome to ZooKeeper!
20 2016-08-27 15:07:04,081 [myid:] - INFO  [main-SendThread(127.0.0.1:2181):ClientCnxn$SendThread@1032] - Opening socket connection to server 127.0.0.1/127.0.0.1:2181. Will not attempt to authenticate using SASL (unknown error)
21 JLine support is enabled
22 2016-08-27 15:07:04,187 [myid:] - INFO  [main-SendThread(127.0.0.1:2181):ClientCnxn$SendThread@876] - Socket connection established to 127.0.0.1/127.0.0.1:2181, initiating session
23 [zk: 127.0.0.1:2181(CONNECTING) 0] 2016-08-27 15:07:04,245 [myid:] - INFO  [main-SendThread(127.0.0.1:2181):ClientCnxn$SendThread@1299] - Session establishment complete on server 127.0.0.1/127.0.0.1:2181, sessionid = 0x156cacb918b0000, negotiated timeout = 5000
24 
25 WATCHER::
26 
27 WatchedEvent state:SyncConnected type:None path:null

如上，表示咱们和ZooKeeper创建了链接，能够经过命令与ZooKeeper进行交互了数据结构

h：帮助列表socket

h
ZooKeeper -server host:port cmd args
    stat path [watch]
    set path data [version]
    ls path [watch]
    delquota [-n|-b] path
    ls2 path [watch]
    setAcl path acl
    setquota -n|-b val path
    history 
    redo cmdno
    printwatches on|off
    delete path [version]
    sync path
    listquota path
    rmr path
    get path [watch]
    create [-s] [-e] path data acl
    addauth scheme auth
    quit 
    getAcl path
    close 
    connect host:port

显示可以执行的命令分布式

命令分类和数据库类似，大概能够分为增删改查四类ui

ZooKeeper数据结构：

大多数时候，咱们队ZooKeeper的操做都是在对节点进行增删改查

经常使用命令：

查询相关指令

ls path：列出path下的文件

[zk: 127.0.0.1:2181(CONNECTED) 4] ls /
[zookeeper]

如上：列出根目录节点下的全部文件，目前就只有一个系统自带的zookeeper节点

stat path：查看节点状态

[zk: 127.0.0.1:2181(CONNECTED) 6] stat /zookeeper
cZxid = 0x0
ctime = Thu Jan 01 08:00:00 CST 1970
mZxid = 0x0
mtime = Thu Jan 01 08:00:00 CST 1970
pZxid = 0x0
cversion = -1
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 0
numChildren = 1

cZxid:建立节点时的事务id

pZxid:子节点列表最后一次被修改的事务id
cversion:节点版本号
dataCersion:数据版本号
aclVerson:acl权限版本号

......

get path：获取指定节点的内容

ls2 path：列出path节点的子节点及状态信息


建立指令

create [-s] [-e] path data acl

1 [zk: 127.0.0.1:2181(CONNECTED) 10] create /node_1 123
2 Created /node_1

如上：在根目录建立了node_1节点，携带数据 123

使用 get /node_1 验证是否添加节点及其数据成功

[zk: 127.0.0.1:2181(CONNECTED) 15] create -e /node_1/node_1_1 234
Created /node_1/node_1_1

建立了一个临时节点（-e），而且携带数据234，使用stat命令查看这个新建的临时节点

[zk: 127.0.0.1:2181(CONNECTED) 16] stat /node_1/node_1_1
cZxid = 0x200000003
ctime = Sat Aug 27 15:27:30 CST 2016
mZxid = 0x200000003
mtime = Sat Aug 27 15:27:30 CST 2016
pZxid = 0x200000003
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x156cacb918b0000
dataLength = 3
numChildren = 0

ephemeralOwner值再也不是0，表示这个临时节点的版本号，若是是永久节点则其值为 0x0

1 [zk: 127.0.0.1:2181(CONNECTED) 1] create -s /node_1/node_1_1 234
2 Created /node_1/node_1_10000000001

经过使用-s参数，建立一个顺序节点，咱们虽然指定的节点名是node_1_1，可是实际上，名称倒是 node_1_10000000001，若是咱们重复执行：

[zk: 127.0.0.1:2181(CONNECTED) 2] create -s /node_1/node_1_1 234
Created /node_1/node_1_10000000002

效果如上

这个特性，咱们能够利用一下，生成在分布式环境下的主键生成器

-s 和 -e 能够同时使用



退出：
quit

[zk: 127.0.0.1:2181(CONNECTED) 19] quit
Quitting...
2016-08-27 15:29:44,760 [myid:] - INFO  [main:ZooKeeper@684] - Session: 0x156cacb918b0000 closed
2016-08-27 15:29:44,763 [myid:] - INFO  [main-EventThread:ClientCnxn$EventThread@519] - EventThread shut down for session: 0x156cacb918b0000

这个时候若是从新登陆，执行 ls /node_1，发现其子节点是空的，建立的node_1_1子节点不见了，那是由于以前建立的时候就已经指定了，咱们建立的是一个临时节点。当客户端会话结束后，临时节点是会被删除了。

修改相关指定：

set path data [version]

[zk: 127.0.0.1:2181(CONNECTED) 14] set /node_1 998
cZxid = 0x200000002
ctime = Sat Aug 27 15:24:39 CST 2016
mZxid = 0x20000000a
mtime = Sat Aug 27 15:38:40 CST 2016
pZxid = 0x200000008
cversion = 5
dataVersion = 2
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 3
numChildren = 3

若是咱们屡次修改，会发现 dataVersion ，也就是数据版本，在不停得发生变化（自增）

若是咱们在set的时候手动去指定了版本号，就必须和上一次查询出来的结果一致，不然就会报错。

这个能够用于咱们在修改节点数据的时候，保证咱们修改前数据没被别人修改过。由于若是别人修改过了，咱们此次修改是不会成功的

删除指令：

delete path [version]

删除指定节点数据，其version参数的做用于set指定一致

delete /node_1/node_1_10000000001

整个节点全删除

注意：delete只能删除不包含子节点的节点，若是要删除的节点包含子节点，使用rmr命令

rmr /node_1