[TOC] # **case语法案例** ## **制作nginx启停脚本** ### **1.条件：** 启动服务命令/application/nginx/sbin/nginx 停止服务命令/application/nginx/sbin/nginx -s stop 实现/etc/init.d/nginxd {start|stop|restart}，并可chkconfig开机自起 ### **2.思路：** 1）nginx启动成功会有一个PID文件，所以根据判断该文件是否存在来确定nginx是开启还是关闭状态 2）通过脚本传入参数start或stop，通过case语句取值判断 3）为了专业，调用系统函数库的action函数 4）对函数及命令允许的返回值进行处理，是脚本看起来更专业、规范 5）通过chkconfig来管理nginx脚本，实现开机自启动 ### **3.脚本** * `cat /etc/init.d/nginxd` ```shell #!/bin/sh # chkconfig: 2345 40 98 # description: Start/Stop Nginx server path=/application/nginx/sbin pid=/application/nginx/logs/nginx.pid RETVAL=0 . /etc/init.d/functions start(){ if [ ! -f $pid ];then $path/nginx RETVAL=$? if [ $RETVAL -eq 0 ];then action "nginx is started" /bin/true return $RETVAL else action "nginx is started" /bin/false return $RETVAL fi else echo "nginx is running" return 0 fi } stop(){ if [ -f $pid ];then $path/nginx -s stop RETVAL=$? if [ $RETVAL -eq 0 ];then action "nginx is stopped" /bin/true return $RETVAL else action "nginx is stopped" /bin/false return $RETVAL fi else echo "nginx is no running" return $RETVAL fi } case "$1" in start) start RETVAL=$? ;; stop) stop RETVAL=$? ;; restart) stop sleep 1 start RETVAL=$? ;; *) echo $"Usage: $0 {start|stop|restart|reload}" exit 1 esac exit $RETVAL ``` `chomod +x /etc/init.d/nginxd` * 参考脚本 linux系统内部有很多值得学习的参考的脚本，空了请研究如下脚本 * /etc/init.d/rpcbind * /etc/init.d/functions * /etc/rc.d/rc.sysinit ## **添加删除openvppn用户的脚本** ### **1.实现要求** **1) 命令用法：** 实现通过传参的方式往/etc/openvpn_authfile.conf里添加用户 `USAGE: sh adduser {-add|-del|-search} username` **2) 传参要求：** -add 表示添加后面接的用户名 -del 表示删除后面接的用户名 -search 表示查找后面接的用户名 **3) 细节要求** 如果用户存在则不能添加，不存在则不能删除，查找结果要给用户明确提示 /etc/openvpn_authfile.conf不能被所有外部用户直接删除及修改 ### **2.具体脚本** * cat /server/scripts/b8.sh ```shell #!/bin/bash . /etc/init.d/functions FILE_PATH=/etc/openvpn_authfile.conf [ -f $filepath ] || touch $filepath usage(){ echo "usage:`basename $0` {-add|-del|-search} username" } if [ $UID -ne 0 ] then echo "you are not root,must use root" exit 1 fi if [ $# -ne 2 ] then usage exit 2 fi case "$1" in -add|-a) shift #位置参数左移，$2替换$1 if grep "^$1$" ${FILE_PATH} >/dev/null 2>&1 then action $"vpnuser,$1 is exist" /bin/false exit else chattr -i ${FILE_PATH} /bin/cp ${FILE_PATH} ${FILE_PATH}.$(date +%F%T) echo "$1" >>${FILE_PATH} [ $? -eq 0 ] && action $"add $1" /bin/true chattr +i ${FILE_PATH} fi ;; -d|-del) shift if [ `grep "\b$1\b" ${FILE_PATH}|wc -l` -lt 1 ] then action $"vpnuser,$1 is not exist" /bin/false exit else chattr -i ${FILE_PATH} /bin/cp ${FILE_PATH} ${FILE_PATH}.$(date +%F%T) sed -i "/^${1}$/d" ${FILE_PATH} [ $? -eq 0 ] && action $"DEL $1" /bin/true chattr +i ${FILE_PATH} exit fi ;; -s|-search) shift if [ `grep -w "$1" ${FILE_PATH}|wc -l` -lt 1 ] then echo $"vpnuser,$1 is no exist." exit else echo $"vpnuser,$1 is exist." exit fi ;; *) usege exit ;; esac ``` > 注意本例中用到的grep三种精确过滤方法 grep -w "oldboy" /file grep "\bodlboy\b" /file grep "^oldboy$" /file