Shell: expect – 自动交互脚本, linux 自动化, shell自动化, expect教程中文版:expect实例

启用选项

  • -c:执行脚本前先执行的命令,可多次使用。
  • -d:debug模式,可以在运行时输出一些诊断信息,与在脚本开始处使用exp_internal 1相似。
  • -D:启用交换调式器,可设一整数参数。
  • -f:从文件读取命令,仅用于使用#!时。如果文件名为”-“,则从stdin读取(使用”./-“从文件名为-的文件读取)。
  • -i:交互式输入命令,使用”exit”或”EOF”退出输入状态。
  • --:标示选项结束(如果你需要传递与expect选项相似的参数给脚本时),可放到#!行:#!/usr/bin/expect --
  • -v:显示expect版本信息。

常用命令

# 命令行参数 
# $argv,参数数组,使用[lindex $argv n]获取,$argv 0为脚本名字
# $argc,参数个数
set username [lindex $argv 1]  # 获取第1个参数
set passwd [lindex $argv 2]    # 获取第2个参数
 
set timeout 30 # 设置超时
 
# spawn是expect内部命令,开启ssh连接
spawn ssh -l username 192.168.1.1
 
# 判断上次输出结果里是否包含“password:”的字符串,如果有则立即返回,否则就等待一段时间(timeout)后返回
expect "password:"
 
# 发送内容ispass(密码、命令等)
send "ispass\r"
 
# 发送内容给用户
send_user "$argv0 [lrange $argv 0 2]\n"
send_user "It's OK\r"
# 执行完成后保持交互状态,控制权交给控制台(手工操作)。否则会完成后会退出。

命令介绍

  • close:关闭当前进程的连接。
  • debug:控制调试器。
  • disconnect:断开进程连接(进程仍在后台运行)。
    • 定时读取密码、执行priv_prog
      send_user "password?\ "
      expect_user -re "(.*)\n"
      for {} 1 {} {
          if {[fork]!=0} {sleep 3600;continue}
          disconnect
          spawn priv_prog
          expect Password:
          send "$expect_out(1,string)\r"
          . . .
          exit
      }
  • exit:退出expect。
  • exp_continue [-continue_timer]:继续执行下面的匹配。
  • exp_internal [-f file] value:

expect脚本可以接受从bash传递过来的参数.可以使用[lindex $argv n]获得,n从0开始,分别表示第一个,第二个,第三个….参数
看下面的expect脚本的例子

#!/usr/bin/expect
set username [lindex $argv 0]
set password [lindex $argv 1]
set server [lindex $argv 2]
send_user  "UserName is $username\n"
send_user  "PassWord is $password\n"
send_user  "Server is $server\n"
send_user "Total arg num is $argc\n"
send_user "last but one arg is[lindex $argv [expr $argc-1]]\n"
if { $argc != 3 && $argc != 2 } {
    send_user "Usage:username password \[server\] \n"
    send_user "\tthe default server is 211.65.64.1 \n"
    exit
}

执行这个文件./launch.exp 1 2 3
屏幕上就会分别打印出参数
send_user用来发送内容给用户。

参数运用方面还有很多技巧
比如$argc 存储了参数个数,args被结构化成一个列表存在argv。$argv0 被初始化为脚本名字。
除此之外,如果你在第一行(#!那行)使用-d (debug参数),可以在运行的时候输出一些很有用的信息
比如你会看见

argv[0] = /usr/bin/expect argv[1] = -d argv[2] = ./launch.exp argv[3] = 1 argv[4] = 2 argv[5] = 3

使用这些也可以完成参数传递

另外在spawn后面加一个interact,会从自动交互状态退出到输入状态,由用户完成剩余的操作.
ecpect也支持使用逻辑结构。基本语法和大多数shell语言;类似,不过使用{}而不是()
另外花括号前后的空格不容小觑,不写就会报错.

— 是用来为划定选项尾的。
当需要像使用选项一样传一个参数,但希望这个参数不要被当作选项解释时,就需要用到这个选项。当阻止其他选项时,可以把它放在”#!”行中
#!/usr/local/bin/expect —
会让所有参数(包括脚本文件名)都存储在argv中。

expect范例

  • 自动telnet会话
    #!/usr/bin/expect -f
    set ip [lindex $argv 0 ]         # 接收第1个参数,作为IP
    set userid [lindex $argv 1 ]     # 接收第2个参数,作为userid
    set mypassword [lindex $argv 2 ] # 接收第3个参数,作为密码
    set mycommand [lindex $argv 3 ]  # 接收第4个参数,作为命令
    set timeout 10                   # 设置超时时间
     
    # 向远程服务器请求打开一个telnet会话,并等待服务器询问用户名
    spawn telnet $ip
        expect "username:"
        # 输入用户名,并等待服务器询问密码
        send "$userid\r"
        expect "password:"
        # 输入密码,并等待键入需要运行的命令
        send "$mypassword\r"
        expect "%"
        # 输入预先定好的密码,等待运行结果
        send "$mycommand\r"
        expect "%"
        # 将运行结果存入到变量中,显示出来或者写到磁盘中
        set results $expect_out(buffer)
        # 退出telnet会话,等待服务器的退出提示EOF
        send "exit\r"
        expect eof
  • 自动建立FTP会话
    #!/usr/bin/expect -f
    set ip [lindex $argv 0 ]         # 接收第1个参数,作为IP
    set userid [lindex $argv 1 ]     # 接收第2个参数,作为Userid
    set mypassword [lindex $argv 2 ] # 接收第3个参数,作为密码
    set timeout 10                   # 设置超时时间
     
    # 向远程服务器请求打开一个FTP会话,并等待服务器询问用户名
    spawn ftp $ip
        expect "username:"
        # 输入用户名,并等待服务器询问密码
        send "$userid\r"
        expect "password:"
        # 输入密码,并等待FTP提示符的出现
        send "$mypassword\r"
        expect "ftp>"
        # 切换到二进制模式,并等待FTP提示符的出现
        send "bin\r"
        expect "ftp>"
        # 关闭ftp的提示符
        send "prompt\r"
        expect "ftp>"
        # 下载所有文件
        send "mget *\r"
        expect "ftp>"
        # 退出此次ftp会话,并等待服务器的退出提示EOF
        send "bye\r"
        expect eof
  • 自动登录ssh执行命令
    #!/usr/bin/expect
    set IP     [lindex $argv 0]
    set USER   [lindex $argv 1]
    set PASSWD [lindex $argv 2]
    set CMD    [lindex $argv 3]
     
    spawn ssh $USER@$IP $CMD
    expect {
        "(yes/no)?" {
            send "yes\r"
            expect "password:"
            send "$PASSWD\r"
            }
        "password:" {send "$PASSWD\r"}
        "* to host" {exit 1}
        }
    expect eof
  • 自动登录ssh
    #!/usr/bin/expect -f  
    set ip [lindex $argv 0 ]         # 接收第1个参数,作为IP
    set username [lindex $argv 1 ]   # 接收第2个参数,作为username
    set mypassword [lindex $argv 2 ] # 接收第3个参数,作为密码
    set timeout 10                   # 设置超时时间 
     
    spawn ssh $username@$ip       # 发送ssh请求
    expect {                      # 返回信息匹配 
    "*yes/no" { send "yes\r"; exp_continue}  # 第一次ssh连接会提示yes/no,继续  
    "*password:" { send "$mypassword\r" }    # 出现密码提示,发送密码  
    } 
    interact        # 交互模式,用户会停留在远程服务器上面
  • 批量登录ssh服务器执行操作范例,设定增量的for循环
    #!/usr/bin/expect
    for {set i 10} {$i <= 12} {incr i} {
        set timeout 30
        set ssh_user [lindex $argv 0]
        spawn ssh -i .ssh/$ssh_user abc$i.com
     
        expect_before "no)?" {
        send "yes\r" }
        sleep 1
        expect "password*"
        send "hello\r"
        expect "*#"
        send "echo hello expect! > /tmp/expect.txt\r"
        expect "*#"
        send "echo\r"
    }
    exit
  • 批量登录ssh并执行命令,foreach语法
    #!/usr/bin/expect
    if {$argc!=2} {
        send_user "usage: ./expect ssh_user password\n"
        exit
    }
    foreach i {11 12} {
        set timeout 30
        set ssh_user [lindex $argv 0]
        set password [lindex $argv 1]
        spawn ssh -i .ssh/$ssh_user root@xxx.yy.com
        expect_before "no)?" {
        send "yes\r" }
        sleep 1
     
        expect "Enter passphrase for key*"
        send "password\r"
        expect "*#"
        send "echo hello expect! > /tmp/expect.txt\r"
        expect "*#"
        send "echo\r"
    }
    exit
  • 另一自动ssh范例,从命令行获取服务器IP,foreach语法,expect嵌套
    #!/usr/bin/expect
    # 使用方法: script_name ip1 ip2 ip3 ...
     
    set timeout 20
    if {$argc < 1} {
      puts "Usage: script IPs"
      exit 1
    }
    # 替换你自己的用户名
    set user "username"
    #替换你自己的登录密码
    set password "yourpassword"
     
    foreach IP $argv {
    spawn ssh $user@$IP
     
    expect \
      "(yes/no)?" {
        send "yes\r"
        expect "password:?" {
          send "$password\r"
        }
      } "password:?" {
        send "$password\r"
    }
     
    expect "$?"
    # 替换你要执行的命令
    send "last\r"
    expect "$?"
    sleep 10
    send "exit\r"
    expect eof
    }
    • tclsh – Simple shell containing Tcl interpreter
      #!/bin/sh
      # -*- tcl -*- \
      exec tclsh $0 "$@"
      package require Expect
      set username [lindex $argv 0]
      set password [lindex $argv 1]
      set argv [lrange $argv 2 end]
      set prompt "(%|#|\$) $"
      foreach ip $argv {
          spawn ssh -t $username@$ip sh
          lappend ids $spawn_id
      }
      expect_before -i ids eof {
          set index [lsearch $ids $expect_out(spawn_id)]
          set ids [lreplace $ids $index $index]
          if [llength $ids] exp_continue
      }
      expect -i ids "(yes/no)\?" {
          send -i $expect_out(spawn_id) yes\r
          exp_continue
      } -i ids "Enter passphrase for key" {
          send -i $expect_out(spawn_id) \r
          exp_continue
      } -i ids "assword:" {
          send -i $expect_out(spawn_id) $password\r
          exp_continue
      } -i ids -re $prompt {
          set spawn_id $expect_out(spawn_id)
          send "echo hello; exit\r"
          exp_continue
      } timeout {
          exit 1
      }

      批量ssh执行命令,用shell调用tclsh方式、多进程同时执行

  • ssh登录过程常规提示文字
    The authenticity of host '192.168.17.35 (192.168.17.35)' can't be established.
    RSA key fingerprint is 25:e8:4c:89:a3:b2:06:ee:de:66:c7:7e:1b:fa:1c:c5.
    Are you sure you want to continue connecting (yes/no)?
    
    
    Warning: Permanently added '192.168.17.35' (RSA) to the list of known hosts.
    Enter passphrase for key '/data/key/my_dsa':
    
    
    Last login: Sun Jan 26 13:39:37 2014 from 192.168.11.143
    [root@master003 ~]#
    
    
    root@192.168.16.90's password:
    
    
    Last login: Thu Jan 23 17:50:43 2014 from 192.168.11.102
    [root@lvsmaster ~]#
  • ssh自动登录expect脚本:ssh.expect
    #!/usr/bin/expect -f
    # Auther:YuanXing
    # Update:2014-02-08
    if {$argc < 4} {
        send_user "Usage:\n  $argv0 IPaddr User Passwd Port Passphrase\n"
        puts stderr "argv error!\n"
        sleep 1
        exit 1
    }
     
    set ip         [lindex $argv 0 ]
    set user       [lindex $argv 1 ]
    set passwd     [lindex $argv 2 ]
    set port       [lindex $argv 3 ]
    set passphrase [lindex $argv 4 ]
    set timeout 6
    if {$port == ""} {
        set port 22
    }
    #send_user "IP:$ip,User:$user,Passwd:$passwd,Port:$port,Passphrase:$passphrase"
    spawn ssh -p $port $user@$ip
     
    expect_before "(yes/no)\?" {
        send "yes\r"}
     
    expect \
    "Enter passphrase for key*" {
        send "$passphrase\r"
        exp_continue
    } " password:?" {
        send "$passwd\r"
        exp_continue
    } "*\[#\$]" {
        interact
    } "* to host" {
        send_user "Connect faild!"
        exit 2
    } timeout {
        send_user "Connect timeout!"
        exit 2
    } eof {
        send_user "Lost connect!"
        exit
    }
  • Mikrotik backup script using ssh and expect
    • http://www.pmoghadam.com/homepage/HTML/mikrotik-backup-script-ssh-expect.html
      #!/bin/bash
      # BY: Pejman Moghadam
      # TAG: mikrotik, ssh, expect, lftp
      # DATE: 2012-05-27 14:42:14 
       
      BACKUP_DIR="/var/backups"
      HOSTNAME="192.168.88.1"
      PORT="22"
      USER="admin"
      PASS="123456"
      TMP=$(mktemp)
      TODAY=$(date +%F)
      FILENAME="$HOSTNAME-$TODAY"
      PATH="/usr/local/sbin:/usr/sbin:/sbin:/usr/local/bin:/usr/bin:/bin"
       
      # create expect script
      cat > $TMP << EOF 
      #exp_internal 1 # Uncomment for debug
      set timeout -1
      spawn ssh -p$PORT $USER@$HOSTNAME
      match_max 100000
      expect -exact "password:"
      send -- "$PASS\r"
      sleep 1
      expect " > "
      send -- "/export file=$FILENAME\r"
      expect " > "
      send -- "/system backup save name=$FILENAME\r"
      expect " > "
      send -- "quit\r"
      expect eof
      EOF
       
      # run expect script
      #cat $TMP # Uncomment for debug
      expect -f $TMP
       
      # remove expect script
      rm $TMP
       
      # download and remove backup files
      # "xfer:clobber on" means overwrite existing files
      cd ${BACKUP_DIR}
      echo "
        set xfer:clobber on
        get ${FILENAME}.rsc
        rm ${FILENAME}.rsc 
        get ${FILENAME}.backup
        rm ${FILENAME}.backup" | 
      lftp -u $USER,$PASS $HOSTNAME
  • 一个简单的脚本程序例子就能实现自动的telnet会话:
      # 假定 $remote_server, $my_user_id, $my_password, 和$my_command 已经读入。
      # 向远程服务器请求打开一个telnet会话,并等待服务器询问用户名
      spawn telnet $remote_server
      expect "username:"
    
      # 输入用户名,并等待服务器询问密码
      send "$my_user_id\r"
      expect "password:"
    
      # 输入密码,并等待键入需要运行的命令
      send "$my_password\r"
      expect "%"
    
      # 输入预先定好的密码,等待运行结果
      send "$my_command\r"
      expect "%"
    
      # 将运行结果存入到变量中,显示出来或者写到磁盘中
      set results $expect_out(buffer)
    
      # 退出telnet会话,等待服务器的退出提示EOF
      send "exit\r"
      expect eof
  • 自动建立FTP会话
      # 向远程服务器请求打开一个FTP会话,并等待服务器询问用户名
      spawn ftp $remote_server
      expect "username:"
    
      # 输入用户名,并等待服务器询问密码
      send "$my_user_id\r"
      expect "password:"
    
      # 输入密码,并等待FTP提示符的出现
      send "$my_password\r"
      expect "ftp>"
    
      # 切换到二进制模式,并等待FTP提示符的出现
      send "bin\r"
      expect "ftp>"
    
      # 关闭ftp的提示符
      send "prompt\r"
      expect "ftp>"
    
      # 下载所有文件
      send "mget *\r"
      expect "ftp>"
    
      # 退出此次ftp会话,并等待服务器的退出提示EOF
      send "bye\r"
      expect eof
    
  • 学校的OpenVPN服务器非常恶心,每当用户登录时间经过60 min 09 s后就把用户踢下线。为了解决这个问日,我使用这个expect脚本来完成这个目的
    #!/usr/bin/expect
    #openVPN 59min 自动重连脚本
    #By http://ihipop.info
    #2010-12-26 11:21
     
    set timeout 30
    set username [lindex $argv 0]
    set password [lindex $argv 1]
    #set server [lindex $argv 2]
    #send_user  "UserName is $username\n"
    #send_user "Filename is $argv0 ,and args No.1-2 is :[lrange $argv 1 2] \n"
    #send_user "Total arg num is $argc\n"
    if { $argc != 3 && $argc != 2 } {
        send_user "Usage:username password \[server\] \n"
        send_user "\tthe default server is 211.65.64.1 \n"
        exit
    }
    spawn openvpn --config  rnas-school.ovpn
    expect "Enter Auth Username:"
    send "$username\r"
    expect "Enter Auth Password:"
    send "$password\r"
    expect "Initialization Sequence Completed"
    #interact
    #等待59min后结束spawn
    #exec sleep 3540
    set timeout 3540
    exit

    然后上层用一个bash的永真循环来调用这个脚本,传递参数即可。

  •  上面的脚本是串行结构,其结果就是,当事态不按照他的发展来的时候,比如出现了异常输出输入请求,但是expect没有匹配到,expect就会一直等待到timeout(默认是10s)
    所以为了增加程序健壮性,应该考虑使用并行结构

    #!/usr/bin/expect
    #openVPN 59min 自动重连脚本
    #By http://ihipop.info
    #2010-12-26 11:21
     
    set timeout 30
    set username [lindex $argv 0]
    set password [lindex $argv 1]
    #set server [lindex $argv 2]
    #send_user  "UserName is $username\n"
    #send_user "Filename is $argv0 ,and args No.1-2 is :[lrange $argv 1 2] \n"
    #send_user "Total arg num is $argc\n"
    if { $argc != 3 && $argc != 2 } {
        send_user "Usage:username password \[server\] \n"
        send_user "\tthe default server is 211.65.64.1 \n"
        exit
    }
    spawn openvpn --config  rnas-school.ovpn
    expect {
     "Enter Auth Username:" {
      send "$username\r"
      exp_continue
     }
     "Enter Auth Password:" {
       send "$password\r"
       exp_continue
     }
     "Initialization Sequence Completed" {
       #interact
       set timeout 3540 
       #set timeout 3   
       exp_continue
     }
     "AUTH: Received AUTH_FAILED control message" {
       #interact
       send_user "AUTH_FAILED\n"
       exit
     }
     eof {
       send_user "eof\n"
       exit
     }
     
     timeout {
       send 
    #!/usr/bin/expect
    #openVPN 59min 自动重连脚本
    #By http://ihipop.info
    #2010-12-26 11:21
     
    set timeout 30
    set username [lindex $argv 0]
    set password [lindex $argv 1]
    #set server [lindex $argv 2]
    #send_user  "UserName is $username\n"
    #send_user "Filename is $argv0 ,and args No.1-2 is :[lrange $argv 1 2] \n"
    #send_user "Total arg num is $argc\n"
    if { $argc != 3 && $argc != 2 } {
        send_user "Usage:username password \[server\] \n"
        send_user "\tthe default server is 211.65.64.1 \n"
        exit
    }
    spawn openvpn --config  rnas-school.ovpn
    expect {
     "Enter Auth Username:" {
      send "$username\r"
      exp_continue
     }
     "Enter Auth Password:" {
       send "$password\r"
       exp_continue
     }
     "Initialization Sequence Completed" {
       #interact
       set timeout 3540 
       #set timeout 3   
       exp_continue
     }
     "AUTH: Received AUTH_FAILED control message" {
       #interact
       send_user "AUTH_FAILED\n"
       exit
     }
     eof {
       send_user "eof\n"
       exit
     }
     
     timeout {
       send \003
       send_user "timeout \n"
       exit
     }
     
    }
    3 send_user "timeout \n" exit } }

    上面看到的是把expect脚本单独运行的例子
    其实也可以和bash脚本结合的很好
    看下面的例子

    #!/bin/bash
    auto_smart_ssh () {
        expect -c "set timeout -1;
                    spawn ssh -o StrictHostKeyChecking=no $2 ${@:3};
                    expect {
                        *assword:* {
                            send $1\r;
                            expect {
                                *denied* {
                                    exit 2;
                                }
                                eof
                            }
                        }
                        eof {
                            exit 1;
                        }
                    }
                    "
        return $?
    }
     
    auto_smart_ssh passwd user@host ls /var
    echo -e "\n---Exit Status: $?"

 

 

本文:Shell: expect – 自动交互脚本, linux 自动化, shell自动化, expect教程中文版:expect实例