Question

我为Nagios编写了这个脚本，以检查服务是否正在运行。但是我需要它来比较2个字符串。完整的脚本如下。

elif [[ $PROCESS_RUNNING1 = "active" && $PROCESS_RUNNING2 = "(running)" || "(exited)" ]]; then

如果我通过shellcheck运行它，那说它是错误的，因为||。但是我如何比较2个字符串，这真的是最有效的吗？这可以缩短吗？

elif [[ $PROCESS_RUNNING1 = "active" && $PROCESS_RUNNING2 = "(running)" || $PROCESS_RUNNING2 = "(exited)" ]]; then

非常欢迎所有其他提示，我还是初学者！

#!/bin/bash
while true
do
  case $1 in
    -s|--service)
        DAEMON=$2
        shift; shift
        ;;
    -*)
        echo "Unknown option: $1"
        echo "Usage: -s or --service <daemon name>"
        exit 1
        ;;
    *)
        break
        ;;
  esac
done

PROCESS_STATUS=$(systemctl status "$DAEMON" | awk 'FNR==3')
PROCESS_RUNNING1=$(systemctl status "$DAEMON" | awk 'FNR==3' | awk '{print $2}')
PROCESS_RUNNING2=$(systemctl status "$DAEMON" | awk 'FNR==3' | awk '{print $3}')

if [[ $(pgrep -f "$DAEMON" | wc -l) -eq 0 ]]; then
        echo "$DAEMON PID not found"
        exit 1
elif [[ $PROCESS_RUNNING1 != "active" ]]; then
        echo "$PROCESS_STATUS"
        echo "is not active"
        exit 2
elif [[ $PROCESS_RUNNING2 != "(running)" || "(exited)" ]]; then
        echo "$PROCESS_STATUS"
        echo "is not running or exited"
        exit 2
elif [[ $PROCESS_RUNNING1 = "active" && $PROCESS_RUNNING2 = "(running)" || "(exited)" ]]; then
        echo "$PROCESS_STATUS"
        exit 0
else    echo "$DAEMON status unknown, please check"
        exit 3
fi

Answer 1

要打击

$PROCESS_RUNNING2 = "(running)" || "(exited)"

与

大致相同

"(exited)" || $PROCESS_RUNNING2 = "(running)"

无论如何，

评估为 true 。

当您在[[ ... ]]中只编写一个字符串而不使用=之类的任何运算符时，对于非空字符串，该字符串将被解释为 true ，而 false 表示空字符串。

你可能意味着

[[ "$PROCESS_RUNNING1" = "active" && "$PROCESS_RUNNING2" = "(running)"
   || "$PROCESS_RUNNING2" = "(exited)" ]]

或甚至更可能是带括号的版本

[[ "$PROCESS_RUNNING1" = "active" &&
   ("$PROCESS_RUNNING2" = "(running)" || "$PROCESS_RUNNING2" = "(exited)") ]]

确保第一个条件始终保持不变。

进一步改进

提示1

PROCESS_STATUS=$(systemctl status "$DAEMON" | awk 'FNR==3')
PROCESS_RUNNING1=$(systemctl status "$DAEMON" | awk 'FNR==3' | awk '{print $2}')
PROCESS_RUNNING2=$(systemctl status "$DAEMON" | awk 'FNR==3' | awk '{print $3}')

可以更有效地编写

PROCESS_STATUS=$(systemctl status "$DAEMON" | awk 'FNR==3')
PROCESS_RUNNING1=$(awk '{print $2}' <<< "$PROCESS_STATUS")
PROCESS_RUNNING2=$(awk '{print $3}' <<< "$PROCESS_STATUS")

提示2

而不是

if [[ $(pgrep -f "$DAEMON" | wc -l) -eq 0 ]]; then

写

if ! pgrep -f "$DAEMON"; then

提示3

支票

[[ $PROCESS_RUNNING2 != "(running)" || "(exited)" ]]

总是 true 。即使你的意思是

[[ $PROCESS_RUNNING2 != "(running)" || $PROCESS_RUNNING2 != "(exited)" ]]

为了评估 false ，$PROCESS_RUNNING2必须同时拥有值"(running)"和("exited")。

提示4

环境和内置变量用 ALLCAPS 编写。在 camelCase 中编写自己的变量，以避免名称冲突。

比较2个字符串

1 个答案:

进一步改进

提示1

提示2

提示3

提示4