#!/bin/bash
###### 这个脚本用于安装多实例的 redis   必须已经安装了 redis-server 才能执行
###### 只能修改 read_variables 里的参数
function read_variables(){
    readonly redis_path="/usr/local/"  # redis 安装路径
    readonly redis_name="redis-4.0.8"  # redis 安装路径
    readonly port="$1"   # 多实例的端口
    readonly password="admin202" # 密码
}

function build_variables(){
    readonly install_path="${redis_path}/$redis_name"
    readonly instance_name="redis_${port}" 

    readonly instalce_service_name="/etc/init.d/redis_${port}"
    readonly instance_conf_name="redis_${port}.conf"

    readonly redis_server_path="${install_path}/src/redis-server"
    readonly redis_client_path="${install_path}/src/redis-cli"
    readonly backup_conf_name="redis_bak.conf"
}

function rEcho(){
    echo -e "\033[31m\033[01m$1\033[0m"
}


function check_env() {
    cd $install_path 
    [ $? -ne 0  ] && rEcho "Error: [ Path Not Found ]! Exit " && exit
    ###########  workdir = redis/
    [ !  -f $redis_server_path  ]  && rEcho "Error: [ redis-server ] Not Found! Exit" && exit
    [ -f $instalce_service_name  ] && rEcho "Error: [ service_name: redis_${port} ] Exist! Exit" && exit
    [ -f $instance_conf_name ] && rEcho "Error: [ conf: $instance_conf_name ] Exist! Exit" && exit
    [ ! -f $backup_conf_name   ] && rEcho "Error: [ conf: $backup_conf_name ] Not Found! Exit" && exit
}

function do_install() {
    #### workdir = redis/
    cat $backup_conf_name  | grep -vw "^#" | grep -vw ^$ > $instance_conf_name
    sed -i '/port/s/6379/'$port'/' $instance_conf_name
    sed -i '/dbfilename/s/dump/dump_'$port'/' $instance_conf_name
    sed -i '/dir/s%./%/%g' $instance_conf_name
    sed -i '/pidfile/s/6379/'$port'/g' $instance_conf_name
    echo "requirepass $password" >> $instance_conf_name
cat << EOF > $instalce_service_name 
#!/bin/sh
#
# Simple Redis init.d script conceived to work on Linux systems
# as it does use of the /proc filesystem.

REDISPORT=${port}
EXEC=${redis_server_path}
AUTHEN=${password}
PIDFILE=/var/run/redis_\${REDISPORT}.pid
CONF=${install_path}/redis_\${REDISPORT}.conf



if [ "\${AUTHEN}" == ""   ] 
then
    CLIEXEC="${redis_client_path} -p \${REDISPORT}"
else 
    CLIEXEC="${redis_client_path} -a \${AUTHEN} -p \${REDISPORT}"
fi


case "\$1" in
    start)
        if [ -f \$PIDFILE ]
        then
                echo "\$PIDFILE exists, process is already running or crashed"
        else
                echo "Starting Redis server..."
                \$EXEC \$CONF &
        fi
        ;;
    stop)
        if [ ! -f \$PIDFILE ]
        then
                echo "\$PIDFILE does not exist, process is not running"
        else
                PID=\$(cat \$PIDFILE)
                echo "Shutdown Redis? Y/N?"
                read -p "Answer: " choose
                if [ "\$choose" != "Y" ] && [ "\$choose" != "y" ]  
                then 
                     echo -e "\\033[01mExit!\\033[0m" && exit 
                fi
                echo "Stopping ..."
                \$CLIEXEC shutdown
                while [ -x /proc/\${PID} ]
                do
                    echo "Waiting for Redis to shutdown ..."
                    sleep 1
                done
                echo "Redis stopped"
        fi
        ;;
    connect)
        \$CLIEXEC
    ;;
    *)
        echo "Please use start or stop or connect as first argument"
        ;;
esac
EOF
    chmod +x $instalce_service_name
        echo -en "\033[01m\033[32m"
        echo "Install [ Redis ${port} ] Success!"
        echo "$instalce_service_name start | service redis_${port} start:  Start Redis Server"
        echo "$instalce_service_name stop  | service redis_${port} stop:   Stop  Redis Server"
        echo -en "\033[0m"
}


function init_redis(){
    read_variables $2
    build_variables
    check_env
    do_install
}

function help1(){
    for i in {1..2} ; do echo ; done 
    echo -e "\033[01mInstall Multiple Instances Redis "
    echo -e "$0 init [ Port ]" 
    echo 
    echo "ForExample: "
    echo -e "$0 init 18001 => Install [ 18001 ] Port Instance\033[0m"
    for i in {1..2}
    do 
        echo 
    done
}


if [ $# -eq 2 ]
then
    [ "$1" != "init" ] && help1 && exit
    init_redis $@
else
    help1
fi