无法在bash脚本中执行期望

Question

我编写了一个bash监视脚本，其中包含期望自动登录到VPN服务的期望。

系统上只有root和User1。当由sudo从终端执行时，它可以按预期工作。

#!/bin/bash
vpn_user=$(getent passwd | grep "/home" | tail -1 | cut -d":" -f1)

write_log(){
    echo "$msg" >> "some.log"
}

log_to_vpn(){
/usr/bin/expect -c '
    set timeout 10
    spawn sudo -u "User1" nordvpn login
    expect "Please enter your login details.\r" {
        expect "Email / Username: " { send "[email protected]\r" }
        sleep 1
        expect "*assword*" { send "User1Password\r" }
        interact }
    '
}

if ( sudo -u "$vpn_user" nordvpn account | grep "Active" ); then
    msg="INFO: $vpn_user is already logged to VPN."
else
    msg="WARNING: Logging to VPN by $(whoami) as $vpn_user."
    log_to_vpn
    sleep 1
    if ( sudo -u "$vpn_user" nordvpn account | grep "Active" ); then
        msg="OK: Logging to VPN as $vpn_user has been successful."
    fi
fi
write_log

从终端消息执行时是：“ INFO：User1已经登录到VPN。”或“ OK：以User1成功登录到VPN。”根据情况是否已经登录User1是否。

问题是，当作为crone作业执行时，该作业不起作用。在这种情况下，some.log仅具有条目[[“警告：以root身份作为User1登录到VPN。”

为什么不起作用？

Answer 1

仅当stdin在tty / pty上但cron作业不在tty / pty上运行时，预期的交互才起作用。

#!/bin/bash
.
.
.

log_to_vpn(){
/usr/bin/expect '
    set timeout 10
    spawn sudo -u "User1" nordvpn login
    expect "Please enter your login details.\r" {
        expect "Email / Username: " { send "[email protected]\r" }
        sleep 1
        expect "*assword*" { send "User1Password\r" }
        # interact }- to replace with below:
        send "exit\r"
        }
        expect eof
    '
}

.
.

问题已解决：）