学习笔记

Shell命令入门

Posted by     "Eric" on Tuesday, January 17, 2023

1.变量

1.1 定义变量

1.1.1 普通变量

  1. 变量名=变量值：变量值必须是一个整体，中间没有特殊字符
  2. 变量名=‘变量值’：单引号中的内容，原样赋值
  3. 变量名=“变量值”：如果双引号里有其他变量，会把变量的结果进行拼接，然后赋值

习惯：数字不加引号，其他默认加双引号

1.1.2 命令变量

  1. 变量名=命令
  2. 变量名=$(命令)

1.2 使用变量

  1. $变量名：非标准写法
  2. ${变量名}：在双引号中使用变量的值，如定义普通变量3
  3. “${变量名}"：标准使用方式

1.3 只读变量

readonly变量名

1.4 删除变量

unset 变量名

2. 数组

  1. 定义数组：数组名=(值1 值2 … 值n)
  2. 给数组的元素赋值：数组名[索引]=值
  3. 获取元素：${数组名[下标]}
  4. 获取长度：${#数组名[*或@]}

3. 条件运算符

条件表达式必须写在[]中，且注意前后保留空格，同时$?可以获取上一条语句的执行结果

3.1 字符串运算符

运算符 说明 举例
= 检测两个字符串是否相等 [ $a = $b ]
!= [ $a != $b ]
-z 检测字符串长度是否为0，不为0返回true [ -z $a ]
-n 检测字符串长度是否不为0，不为0返回true [ -n $a ]
$ [ $a ]

更多可参考http://tiswww.case.edu/php/chet/bash/bash.html#lbBW

3.2 关系运算符

只支持数字，不支持字符串

运算符 说明
-eq 相等
-ne 不相等
-gt 大于
-lt 小于
-ge 大于等于
-le 小于等于

3.3 布尔运算符

运算符 说明
! 取反
-o 或运算
-a 与运算

3.4 逻辑运算符

必须写在双中括号中[[ ]]，且具有短路功能

运算符 说明
&& 与运算
|| 或运算

4. if语句

if [ 条件 ]
then
	语句体
fi

if [ 条件 ]
then
	语句体
else
	语句体
fi

if [ 条件 ]
then
	语句体
elif [ 条件 ]
	语句体
else
	语句体
fi

5. for语句

for 变量 in 范围
do
	循环体
done
# eg:
for var in A B C D E F
do
	echo "${var}"
done

6. while语句

while 条件
do
	循环体
done
#eg. 
a=1
while [ "${a}" -le 10 ]
do
	echo "${a}"
	((a++))
done

7. demo

start.sh

bashPath=/usr/local/app
trpcPath=/usr/local/application/bin
logFile=$bashPath/startScript.log
server=datatalk-webserver-0.0.1-SNAPSHOT.jar
projectLogPath=/usr/local/app/datatalk/logs

source /etc/profile

if [ ! -d $bashPath ];then
    mkdir -p $bashPath
fi

if [ ! -d $projectLogPath ];then
    mkdir -p $projectLogPath
fi
sudo -- sh -c -e "echo '9.146.161.37 api.tapd.oa.com apiv2.tapd.oa.com' >> /etc/hosts"
#rasp setup
hasOuternet=$(echo $SUMERU_SERVER | grep "outer_net")
if [[ $env == "prod" ]] && [[ $hasOuternet != "" ]]; then
  echo 'use rasp agent'
  cd /usr/share/java
  sudo rm -f tencent.rasp-1.0.2.jar
  sudo rm -f libmsg_queue.so
  sudo rm -f tencent.rasp.jar
  sudo wget https://mirrors.tencent.com/repository/generic/RASP_JAVA/v1.0.2/tencent.rasp-1.0.2.jar
  sudo wget https://mirrors.tencent.com/repository/generic/RASP_JAVA/v1.0.2/libmsg_queue.so
  sudo ln -s /usr/share/java/tencent.rasp-1.0.2.jar /usr/share/java/tencent.rasp.jar
  raspAgent="-javaagent:/usr/share/java/tencent.rasp.jar"
fi

if [[ $env == "prod" ]]; then
  apm_service_name=beacon-datatalk
elif [[ $env == "pre" ]]; then
  apm_service_name=beacon-datatalk-gray
elif [[ $env == "public_prod" ]]; then
  apm_service_name=beacon-datatalk-public_prod
elif [[ $env == "public_pre" ]]; then
  apm_service_name=beacon-datatalk-public_pre
else
  apm_service_name=beacon-datatalk-test
fi

echo "apm_service_name=${apm_service_name}">> $logFile

#apm setup
cd /usr/local/app/
rm -rf apm*
wget -O apm.tar.gz http://apm-75118.cos.sz.gfp.tencent-cloud.com/f02ee61e8cd34e579fca722cab7d5a75db/apm-agent-0.0.4-SNAPSHOT.tar.gz
if [ $? -eq 0 ]; then
    tar -xzvf apm.tar.gz
    echo "agent.service_name=${apm_service_name}" >> /usr/local/app/apm-agent/config/agent.config
    echo "plugin.cgi.extract_expression_response=response" >> /usr/local/app/apm-agent/config/agent.config
    echo "plugin.cgi.extract_expression_response_code=response.code" >> /usr/local/app/apm-agent/config/agent.config
    echo "plugin.cgi.extract_expression_response_message=response.message" >> /usr/local/app/apm-agent/config/agent.config
    # 设置0代表正确的 biz_code
    echo "plugin.cgi.success_response_code=0" >> /usr/local/app/apm-agent/config/agent.config

    # 过滤心跳
    echo "agent.ignore_path=/" >> /usr/local/app/apm-agent/config/agent.config

    if [[ $env != "prod" ]] || [[ $cgiRecord == "off" ]];then
        echo "plugin.cgi.record_cgi_scene=false" >> /usr/local/app/apm-agent/config/agent.config
        echo "plugin.cgi.record_cgi_scene=false" >>$logFile
    fi
    cp /usr/local/app/apm-agent/optional-plugins/apm-jdbc-commons-0.0.4-SNAPSHOT.jar /usr/local/app/apm-agent/plugins/
    cp /usr/local/app/apm-agent/optional-plugins/apm-mysql-5.x-plugin-0.0.4-SNAPSHOT.jar /usr/local/app/apm-agent/plugins/
    cp /usr/local/app/apm-agent/optional-plugins/apm-mysql-6.x-plugin-0.0.4-SNAPSHOT.jar /usr/local/app/apm-agent/plugins/
    cp /usr/local/app/apm-agent/optional-plugins/apm-mysql-8.x-plugin-0.0.4-SNAPSHOT.jar /usr/local/app/apm-agent/plugins/
    cp /usr/local/app/apm-agent/optional-plugins/apm-mysql-commons-0.0.4-SNAPSHOT.jar /usr/local/app/apm-agent/plugins/

else
    echo "apm download failed"
fi


#混沌工程----------------start
if [ "${SUMERU_ENV}" = "formal" ]; then
        export ChaosNamespace=Production
else
        export ChaosNamespace=Development
fi
export ChaosService=chaos.trpc.${SUMERU_APP}.${SUMERU_SERVER}-${SUMERU_ENV}
echo "ChaosService: ${ChaosService}" >> $logFile
echo "ChaosNamespace: ${ChaosNamespace}" >> $logFile
# 判断agent是否存在
processName="chaos_agent"
processNum=`ps -ef | grep -w  $processName | grep -v grep | wc -l`
echo "processNum: ${processNum}" >> $logFile
if [ 0 == $processNum ]
then
  # 执行安装agent脚本
  sudo -S su root -c "export chaos_port=$chaos_port ; cd /usr/local/ && curl http://chaos.oa.com/chaosblade/install | bash -s ${ChaosService}_${ChaosNamespace}"
fi
#混沌工程----------------end


sudo chmod 777  /etc/resolv.conf
echo  >  /etc/resolv.conf
echo  "nameserver 10.165.87.54" >  /etc/resolv.conf
echo  "nameserver 10.165.86.15" >>  /etc/resolv.conf
sudo chmod 644  /etc/resolv.conf
chmod a+x $trpcPath/$server
if [[ $env == "wechat" ]] || [[ $env == "wechattest" ]];then
    nohup java $raspAgent -javaagent:/usr/local/app/apm-agent/apm-agent-latest.jar $app_jvm_params -XX:MetaspaceSize=128M -XX:MaxMetaspaceSize=1024M -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSCompactAtFullCollection -XX:ErrorFile=/usr/local/app/java_error.log -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/usr/local/app/ -Xloggc:/usr/local/app/gc.log -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=10 -XX:GCLogFileSize=4096k -jar $trpcPath/$server  2>&1 | tee  $trpcPath/server.log >> $trpcPath/server.log 2>&1 &
else
    nohup java -Dplugins.telemetry.tpstelemetry.metrics.ip=$HOST_IP  -Dplugins.telemetry.tpstelemetry.metrics.port=$METRICS_PORT  $raspAgent -javaagent:/usr/local/app/apm-agent/apm-agent-latest.jar $app_jvm_params -XX:MetaspaceSize=128M -XX:MaxMetaspaceSize=1024M -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=70 -XX:+UseCMSCompactAtFullCollection -XX:ErrorFile=/usr/local/app/java_error.log -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/usr/local/app/ -Xloggc:/usr/local/app/gc.log -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=10 -XX:GCLogFileSize=4096k -jar $trpcPath/$server  2>&1 | tee  $trpcPath/server.log >> $trpcPath/server.log 2>&1 &
fi
sleep 3
num=`ps -ef |grep $trpcPath/$server |grep -v grep|wc -l`
echo "the num of process after start is $num">>$logFile
if [ $num -lt 1 ];then
    echo "the process is not exit after start ">>$logFile
    exit 1
fi

#探活检测
CHECK_URL="http://127.0.0.1:$main_port/server/example/hello"
CHECK_HTTP_CODE=401
HTTP_CODE=`curl -I -m 10 -o /dev/null -s -w %{http_code}"\n" $CHECK_URL`
startProcessFail=10002

echo $HTTP_CODE
CHECK_COUNT=0
until [ ${HTTP_CODE} == $CHECK_HTTP_CODE ]
do
        sleep 1s
        HTTP_CODE=`curl -I -m 10 -o /dev/null -s -w %{http_code}"\n" $CHECK_URL`
        echo "check url http code on $CHECK_URL, http code $CHECK_HTTP_CODE excepted, now is $HTTP_CODE" >> $logFile
        echo $HTTP_CODE
        CHECK_COUNT=$((${CHECK_COUNT} + 1))
        if [ $CHECK_COUNT -eq 200 ]; then
          exit $startProcessFail
        fi
done

exit 0

stop.sh

#!/bin/bash

bashPath=/usr/local/app
trpcPath=/usr/local/application/bin
logFile=$bashPath/startScript.log
server=datatalk-webserver-0.0.1-SNAPSHOT.jar

pidInfo=$(ps -ef | grep "$trpcPath/$server" | grep -v grep | awk '{print $2}')


for pid in $pidInfo;do
	kill -9 $pid
done

#check process num
num=$(ps -ef | grep "$trpcPath/$server" | grep -v grep |wc -l)

if [ $num -gt 0 ];then
	echo "`date` after stop process in force way the processNum is $num still bigger than 0">>$logFile
	exit 1
fi
exit 0
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