SHELL脚本编程-expect
SHELL脚本编程-expect
作者：尹正杰
版权声明：原创作品，谢绝转载！否则将追究法律责任。
一.expect概述
1>.expect介绍
expect 是由Don Libes基于Tcl（ Tool Command Language ）语言开发的，主要应用于自动化交互式操作的场景，借助Expect处理交互的命令，可以将交互过程如：ssh登录，ftp登录等写在一个脚本上，使之自动化完成。尤其适用于需要对多台服务器执行相同操作的环境中，可以大大提高系统管理人员的工作效率。
2>.expect命令
expect 语法：
expect [选项] [ -c cmds ] [ [ -[f|b] ] cmdfile ] [ args ]
常用选项
-c：从命令行执行expect脚本，默认expect是交互地执行的
示例：expect -c 'expect "\n" {send "pressed enter\n"}
-d：可以输出输出调试信息
示例：expect -d ssh.exp
expect中相关命令
spawn：
启动新的进程
send：
用于向进程发送字符串
expect：
从进程接收字符串
interact：
允许用户交互
exp_continue
匹配多个字符串在执行动作后加此命令
3>.安装expect软件包
[root@node101.yinzhengjie.org.cn ~]# yum info expect
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.huaweicloud.com
* epel: mirrors.aliyun.com
* extras: mirrors.huaweicloud.com
* updates: mirrors.aliyun.com
Available Packages
Name : expect
Arch : x86_64
Version : 5.45
Release : .el7_1
Size : k
Repo : base//x86_64
Summary : A program-script interaction and testing utility
URL : http://expect.nist.gov/
License : Public Domain
Description : Expect is a tcl application for automating and testing
: interactive applications such as telnet, ftp, passwd, fsck,
: rlogin, tip, etc. Expect makes it easy for a script to
: control another program and interact with it.
:
: This package contains expect and some scripts that use it. [root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# yum info expect #查看expect软件包相关信息
[root@node101.yinzhengjie.org.cn ~]# yum -y install expect
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
epel/x86_64/metalink | 8.6 kB ::
* base: mirrors.aliyun.com
* epel: mirrors.aliyun.com
* extras: ap.stykers.moe
* updates: mirrors.aliyun.com
base | 3.6 kB ::
epel | 5.3 kB ::
extras | 2.9 kB ::
updates | 2.9 kB ::
(/): epel/x86_64/updateinfo | 1.0 MB ::
(/): epel/x86_64/primary_db | 6.9 MB ::
Resolving Dependencies
--> Running transaction check
---> Package expect.x86_64 :5.45-.el7_1 will be installed
--> Processing Dependency: libtcl8..so()(64bit) for package: expect-5.45-.el7_1.x86_64
--> Running transaction check
---> Package tcl.x86_64 :8.5.-.el7 will be installed
--> Finished Dependency Resolution Dependencies Resolved ============================================================================================================================================================================
Package Arch Version Repository Size
============================================================================================================================================================================
Installing:
expect x86_64 5.45-.el7_1 base k
Installing for dependencies:
tcl x86_64 :8.5.-.el7 base 1.9 M Transaction Summary
============================================================================================================================================================================
Install Package (+ Dependent package) Total download size: 2.1 M
Installed size: 4.9 M
Downloading packages:
(/): expect-5.45-.el7_1.x86_64.rpm | kB ::
(/): tcl-8.5.-.el7.x86_64.rpm | 1.9 MB ::
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Total kB/s | 2.1 MB ::
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : :tcl-8.5.-.el7.x86_64 /
Installing : expect-5.45-.el7_1.x86_64 /
Verifying : :tcl-8.5.-.el7.x86_64 /
Verifying : expect-5.45-.el7_1.x86_64 / Installed:
expect.x86_64 :5.45-.el7_1 Dependency Installed:
tcl.x86_64 :8.5.-.el7 Complete!
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# yum -y install expect #安装expect工具
二.expect最常用的语法(tcl语言:模式-动作)
1>.expect的单分支语法
[root@node101.yinzhengjie.org.cn ~]# expect
expect1.> expect "hi" {send "say hi\n"} #捕捉用户输入的"hi",然后给用户发送"say hi\n"
hi #这一行是我输入的，由于被我上面定义的语句捕捉到了，下面一行的输出信息就是我之前自定义的字符串信息。
say hi
expect1.> exit #如果不想使用该程序了可以输入"exit"来正常退出交互式界面
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]#
2>.expect的多分支语法
[root@node101.yinzhengjie.org.cn ~]# expect
expect1.> expect "hi" {send "say hi\n"}\
+> "bye" {send "byebye\n"}
bye
byebye
expect1.> exit
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# expect #匹配hi,hello,bye任意字符串时，执行相应输出。上面的写法和下面的写法功能是相同的。
expect1.> expect {
+> "hi" {send "You said hi\n"}
+> "hehe" {send "hehe yourself\n"}
+> "bye" {send "Good bye\n"}
+> }
bye
Good bye
expect1.>
expect1.> exit
[root@node101.yinzhengjie.org.cn ~]#
三.expect脚本案例实战
1>.spawn(启动新的进程)案例
[root@node101.yinzhengjie.org.cn ~]# ll .ssh/
total
-rw-------. root root Jul : authorized_keys
-rw-------. root root Jul : id_rsa
-rw-r--r--. root root Jul : id_rsa.pub
-rw-r--r--. root root Jul : known_hosts
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# rm -rf .ssh
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# ll /etc/issue
-rw-r--r--. root root Nov /etc/issue
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# ll backup/
total
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/scp_expect.sh
#!/usr/bin/expect #注意，这一行需要写expect命令的执行路径
#
#********************************************************************
#Author: yinzhengjie
#QQ:
#Date: --
#FileName： shell/scp_expect.sh
#URL: http://www.cnblogs.com/yinzhengjie
#Description： The test script
#Copyright notice: original works, no reprint! Otherwise, legal liability will be investigated.
#******************************************************************** spawn scp /etc/issue root@172.30.1.101:/root/backup expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "yinzhengjie\n" }
} expect eof
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# chmod +x shell/scp_expect.sh #添加执行权限
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# ./shell/scp_expect.sh #执行脚本后,我们发现无需像之前那样手动输出"yes"和密码啦~取而代之的是脚本帮咱们干活了。
spawn scp /etc/issue root@172.30.1.101:/root/backup
The authenticity of host '172.30.1.101 (172.30.1.101)' can't be established.
ECDSA key fingerprint is SHA256:KEchoZnVBkijeoWfG2nvx2ptthsXv7IjkxIJYule57g.
ECDSA key fingerprint is MD5::c8:f5:6e:5f:cf::ec:c4:::d2:d0::3c:da.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '172.30.1.101' (ECDSA) to the list of known hosts.
root@172.30.1.101's password:
issue % .2KB/s :
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# ll backup
total
-rw-r--r-- root root Nov : issue
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/scp_expect.sh
2>.interact(允许用户交互)案例
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect1.sh
#!/usr/bin/expect
#
#********************************************************************
#Author: yinzhengjie
#QQ:
#Date: --
#FileName： shell/scp_expect.sh
#URL: http://www.cnblogs.com/yinzhengjie
#Description： The test script
#Copyright notice: original works, no reprint! Otherwise, legal liability will be investigated.
#******************************************************************** spawn ssh yinzhengjie@172.30.1.101 expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "yinzhengjie\n" }
} interact
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# ./shell/ssh_expect1.sh
spawn ssh yinzhengjie@172.30.1.101
yinzhengjie@172.30.1.101's password:
Last login: Sat Nov :: from 172.30.1.101
[yinzhengjie@node101.yinzhengjie.org.cn ~]$
[yinzhengjie@node101.yinzhengjie.org.cn ~]$ who
yinzhengjie pts/ -- : (172.30.1.101)
root pts/ -- : (172.30.1.254)
root pts/ -- : (172.30.1.254)
[yinzhengjie@node101.yinzhengjie.org.cn ~]$
[yinzhengjie@node101.yinzhengjie.org.cn ~]$ exit
logout
Connection to 172.30.1.101 closed.
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect1.sh
3>.变量使用案例
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect2.sh
#!/usr/bin/expect
#
#********************************************************************
#Author: yinzhengjie
#QQ:
#Date: --
#FileName： shell/scp_expect.sh
#URL: http://www.cnblogs.com/yinzhengjie
#Description： The test script
#Copyright notice: original works, no reprint! Otherwise, legal liability will be investigated.
#******************************************************************** set host 172.30.1.101
set user yinzhengjie
set password yinzhengjie spawn ssh ${user}@${host} expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "${password}\n" }
} interact
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# ./shell/ssh_expect2.sh
spawn ssh yinzhengjie@172.30.1.101
yinzhengjie@172.30.1.101's password:
Last login: Sat Nov :: from 172.30.1.101
[yinzhengjie@node101.yinzhengjie.org.cn ~]$
[yinzhengjie@node101.yinzhengjie.org.cn ~]$ whoami
yinzhengjie
[yinzhengjie@node101.yinzhengjie.org.cn ~]$
[yinzhengjie@node101.yinzhengjie.org.cn ~]$ exit
logout
Connection to 172.30.1.101 closed.
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect2.sh
4>.位置参数案例
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect3.sh
#!/usr/bin/expect
#
#********************************************************************
#Author: yinzhengjie
#QQ:
#Date: --
#FileName： shell/scp_expect.sh
#URL: http://www.cnblogs.com/yinzhengjie
#Description： The test script
#Copyright notice: original works, no reprint! Otherwise, legal liability will be investigated.
#******************************************************************** set host [lindex $argv ]
set user [lindex $argv ]
set password [lindex $argv ] spawn ssh ${user}@${host} expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "${password}\n" }
} interact
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# ./shell/ssh_expect3.sh 172.30.1.101 yinzhengjie yinzhengjie
spawn ssh yinzhengjie@172.30.1.101
yinzhengjie@172.30.1.101's password:
Last login: Sat Nov :: from 172.30.1.101
[yinzhengjie@node101.yinzhengjie.org.cn ~]$
[yinzhengjie@node101.yinzhengjie.org.cn ~]$ whoami
yinzhengjie
[yinzhengjie@node101.yinzhengjie.org.cn ~]$
[yinzhengjie@node101.yinzhengjie.org.cn ~]$ exit
logout
Connection to 172.30.1.101 closed.
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect3.sh
5>.登录后执行多个命令案例
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect4.sh
#!/usr/bin/expect
#
#********************************************************************
#Author: yinzhengjie
#QQ:
#Date: --
#FileName： shell/scp_expect.sh
#URL: http://www.cnblogs.com/yinzhengjie
#Description： The test script
#Copyright notice: original works, no reprint! Otherwise, legal liability will be investigated.
#******************************************************************** set host [lindex $argv ]
set user [lindex $argv ]
set password [lindex $argv ]
set createuser [lindex $argv ]
set createpasswd [lindex $argv ] spawn ssh ${user}@${host} expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "${password}\n" }
} expect "]#" { send "useradd ${createuser}\n" }
expect "]#" { send "echo ${createpasswd} |passwd --stdin ${createuser}\n" }
expect "]#" { send "who\n" }
send "exit\n"
expect eof
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# who
root pts/ -- : (172.30.1.254)
root pts/ -- : (172.30.1.254)
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# id jason
id: jason: no such user
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# ./shell/ssh_expect4.sh 172.30.1.101 root yinzhengjie jason
spawn ssh root@172.30.1.101
root@172.30.1.101's password:
Last login: Sat Nov :: from 172.30.1.101
[root@node101.yinzhengjie.org.cn ~]# useradd jason
[root@node101.yinzhengjie.org.cn ~]# echo |passwd --stdin jason
Changing password for user jason.
passwd: all authentication tokens updated successfully.
[root@node101.yinzhengjie.org.cn ~]# who
root pts/ -- : (172.30.1.101)
root pts/ -- : (172.30.1.254)
root pts/ -- : (172.30.1.254)
[root@node101.yinzhengjie.org.cn ~]# exit
logout
Connection to 172.30.1.101 closed.
[root@node101.yinzhengjie.org.cn ~]# who
root pts/ -- : (172.30.1.254)
root pts/ -- : (172.30.1.254)
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# id jason
uid=(jason) gid=(jason) groups=(jason)
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect4.sh
6>.shell脚本调用expect
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect5.sh
#!/bin/bash
#
#********************************************************************
#Author: yinzhengjie
#QQ:
#Date: --
#FileName： shell/ssh_expect5.sh
#URL: http://www.cnblogs.com/yinzhengjie
#Description： The test script
#Copyright notice: original works, no reprint! Otherwise, legal liability will be investigated.
#******************************************************************** ip=$
user=$
password=$ expect <<EOF
set timeout
spawn ssh $user@$ip
expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "$password\n" }
} expect "]#" { send "useradd jason2019\n" }
expect "]#" { send "echo yinzhengjie |passwd --stdin jason2019\n" }
expect "]#" { send "who\n" }
expect "]#" { send "exit\n" }
expect eof
EOF
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# who
root pts/ -- : (172.30.1.254)
root pts/ -- : (172.30.1.254)
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# id jason2019
id: jason2019: no such user
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# bash shell/ssh_expect5.sh 172.30.1.101 root yinzhengjie
spawn ssh root@172.30.1.101
root@172.30.1.101's password:
Last login: Sat Nov :: from 172.30.1.101
[root@node101.yinzhengjie.org.cn ~]# useradd jason2019
[root@node101.yinzhengjie.org.cn ~]# echo yinzhengjie |passwd --stdin jason2019
Changing password for user jason2019.
passwd: all authentication tokens updated successfully.
[root@node101.yinzhengjie.org.cn ~]# who
root pts/ -- : (172.30.1.101)
root pts/ -- : (172.30.1.254)
root pts/ -- : (172.30.1.254)
[root@node101.yinzhengjie.org.cn ~]# exit
logout
Connection to 172.30.1.101 closed.
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# id jason2019
uid=(jason2019) gid=(jason2019) groups=(jason2019)
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# who
root pts/ -- : (172.30.1.254)
root pts/ -- : (172.30.1.254)
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect5.sh
7>.模拟给集群批量创建用户的脚本
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect6.sh
#!/bin/bash
#
#********************************************************************
#Author: yinzhengjie
#QQ:
#Date: --
#FileName： shell/ssh_expect5.sh
#URL: http://www.cnblogs.com/yinzhengjie
#Description： The test script
#Copyright notice: original works, no reprint! Otherwise, legal liability will be investigated.
#******************************************************************** while read ip ;do
user=root
password=yinzhengjie expect <<EOF
set timeout
spawn ssh $user@$ip
expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "$password\n" }
} expect "]#" { send "useradd hadoop\n" }
expect "]#" { send "echo yinzhengjie |passwd --stdin hadoop\n" }
expect "]#" { send "who\n" }
expect "]#" { send "exit\n" }
expect eof
EOF
done < /root/shell/iplist.txt
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/iplist.txt #咱们这里定义了需要连接集群的主机IP
172.30.1.101
172.30.1.102
172.30.1.103
172.30.1.104
172.30.1.105
172.30.1.106
172.30.1.107
172.30.1.108
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# bash shell/ssh_expect6.sh #执行脚本后发现会有很多输出信息，由于我试验的时候之开机了172.30.1.101这台虚拟机，其它虚拟机全部关机了，结果脚本只在开机的虚拟机中执行成功啦，其它主机报错提示找不到主机路由。
spawn ssh root@172.30.1.101
root@172.30.1.101's password:
Last login: Sat Nov :: from 172.30.1.101
[root@node101.yinzhengjie.org.cn ~]# useradd hadoop
[root@node101.yinzhengjie.org.cn ~]# echo yinzhengjie |passwd --stdin hadoop
Changing password for user hadoop.
passwd: all authentication tokens updated successfully.
[root@node101.yinzhengjie.org.cn ~]# who
root pts/ -- : (172.30.1.101)
root pts/ -- : (172.30.1.254)
root pts/ -- : (172.30.1.254)
[root@node101.yinzhengjie.org.cn ~]# exit
logout
Connection to 172.30.1.101 closed.
spawn ssh root@172.30.1.102
ssh: connect to host 172.30.1.102 port : No route to host
expect: spawn id exp6 not open
while executing
"expect "]#" { send "useradd hadoop\n" }"
spawn ssh root@172.30.1.103
ssh: connect to host 172.30.1.103 port : No route to host
expect: spawn id exp6 not open
while executing
"expect "]#" { send "useradd hadoop\n" }"
spawn ssh root@172.30.1.104
ssh: connect to host 172.30.1.104 port : No route to host
expect: spawn id exp6 not open
while executing
"expect "]#" { send "useradd hadoop\n" }"
spawn ssh root@172.30.1.105
ssh: connect to host 172.30.1.105 port : No route to host
expect: spawn id exp6 not open
while executing
"expect "]#" { send "useradd hadoop\n" }"
spawn ssh root@172.30.1.106
ssh: connect to host 172.30.1.106 port : No route to host
expect: spawn id exp6 not open
while executing
"expect "]#" { send "useradd hadoop\n" }"
spawn ssh root@172.30.1.107
ssh: connect to host 172.30.1.107 port : No route to host
expect: spawn id exp6 not open
while executing
"expect "]#" { send "useradd hadoop\n" }"
spawn ssh root@172.30.1.108
ssh: connect to host 172.30.1.108 port : No route to host
expect: spawn id exp6 not open
while executing
"expect "]#" { send "useradd hadoop\n" }"
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# id hadoop #很显然，只有172.30.1.101主机命令执行成功了。
uid=(hadoop) gid=(hadoop) groups=(hadoop)
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]#
[root@node101.yinzhengjie.org.cn ~]# cat shell/ssh_expect6.sh
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