Shell 脚本小试牛刀（5） -- 超便捷脚本之高速ssh 登录其它主机

假设你也是以Linux 为工作环境的童鞋，那么此文真是捷报！由于我的学习/工作中（特别是近期玩耍树莓派）常常会使用到ssh 登录其它主机，而每次使用ssh 登录都须要输入老长一大串让我非常烦。所以我写了这个脚本来简化我的ssh 过程。

使用这个脚本。假设我想登录一台机器。我仅仅要使用 $~/easy_ssh.sh 然后选择一项就可登录，即使当前没有我要登录的机器选项。我仅仅要输入一次并保存，以后我也能够非常快的登录到这台电脑。

#!/bin/bash
# (C) 2014 Yunlong Zhou <reaper888@yeah.net>      
# Under licence  GPLv2
# File :   easy_ssh.sh 
# Introduction:      
#       This script is using for ssh Linux hosts quickly
# Advises:
#		Copy this script to a easy use place, such as ~, so that you can use it very easily.
#		Besides, this script will create a ".hostlist" local file to temp the hosts, so if you want to move the script, remembermove the temp file too.
# Last Modify:
#		2014-7-2
# Useage :
#		$ /bin/bash easy_ssh.sh 	(chmod +x easy_ssh.sh ; ./easy_ssh.sh)
#		Now you have  hosts on your config:
#			 0 : Inupt other host manually
#			 1 : pi@192.168.2.226
#			 2 : long@192.168.2.222	
#		======================================
#		Please input your choice: 1
#		You choose 1, and Now I will try to connect pi@192.168.2.226
#		pi@192.168.2.226's password: 
#		 ...


function copy_array #from_name #to_name
{	
	from_name=$1
	from_len=${#from_name[@]}
	to_name=$2
	to_len=${#to_name[@]}
	for((i=1; i<$from_len; i++))
	do
		$to_name[$to_len]=${$from_name[$i]}
		((to_len++))
	done
}


function get_current_hosts # array_name 
{
	copy_array $1 array_name
	echo ${array_name[*]}
	ls $host_file &> /dev/null
	if [ $? -ne 0  ]; then
		touch $host_file
	else
		while read READLINE
		do
			if [ $READLINE != ' ' ];then
				len=${#array_name[@]}
				#echo -e "\t $len $READLINE"
				array_name[$len]=$READLINE
			fi
		done < $host_file
	fi
}


function store_hostmessage #user_input
{
	if read -t 30 -p "Do you want to add this host message to config file?[Y/n]"
	then 
		store_flag=$REPLY
		case "$store_flag" in
			"Y"|"YES"|"YEs"|"Yes"|"y"|"yes"|"yeS"|"yES"|"ye")
				echo $1 >>$host_file
				echo "Yep, Store complete"	;;
			"N"|"NO"|"No"|"n"|"no"|"nO")
				echo "Ok, do not store, see you later" ;;
			*)
				echo "Can't recognize, won't store, please input right options next time";;
		esac
	else
        echo -e "\nOh, you are too slow or away"
        exit -1
    fi
}


function get_user_manual_input 
{
	if read -t 180 -p "Please input the host manually(in user@IP_addr format):  "
    then
        user_input=$REPLY
     	user_name=${user_input%@*}
		user_ip=${user_input##*@}
		ping -c 1 $user_ip &> /dev/null
		if [ $? -eq 0 ]; then
			ssh $user_input
			store_hostmessage $user_input $host_file
		else
			echo "The IP address is not accessable, please check again"
		fi
    else
        echo -e "\nOh, you are too slow or away"
        exit -1
    fi
}


function get_user_input #array_name 
{
	copy_array $1 array_name
	array_len=${#array_name[@]}
	if read -t 40  -p "Please input your choice: "
	then
	    user_input=$REPLY
	    if [ $user_input == "0" ] ;then
			echo "You choose 0"
			get_user_manual_input 
		elif [ $(($user_input-0)) -gt 0 -a $(($user_input-$array_len)) -le 0 ]; then
			echo "You choose $user_input, and Now I will try to connect ${array_name[$user_input-1]}"
			ssh ${array_name[$(($user_input-1))]}
		else
			echo "Please input right choice"
		fi
		
	else
	    echo -e "\nYou are too slow!"
	    exit -1
	fi
}


function echo_hosts_get_input #array_name 
{
	copy_array $1 array_name
	array_len=${#array_name[@]}
	if [ $array_len -ne 0 ]; then
		echo "Now you have $arrar_len hosts on your config:"
		cur=1
		echo -e "\t 0 : Inupt other host manually"
		for i in ${array_name[*]}
		do
			echo -e "\t $cur : $i"
			((cur++))
		done
		echo "======================================"
		get_user_input ${array_name[*]} $host_file 
	else
		echo -e "Sorry that have no hosts message"
		get_user_manual_input
	fi
	echo ""
}


host=()
path=${0%/*}
host_file=$path/.hostlist
echo $host_file
get_current_hosts ${host[*]} $host_file
echo_hosts_get_input ${host[*]} $host_file

眼下的不足：

当前仅仅支持普通的ssh 登录，对于输入须要 -p port登录部分还是没有採取比較好的处理。下次会解决！

此外，个人感觉使用shell 脚本实现尽管不是非常复杂，可是使用python 实现应该会更加方便快捷。

希望你使用的愉快。

=================================

更新日志： 2014.7.12

之前公布的版本号中。会直接在你使用脚本时所在的位置下查找.hostlist 文件。可是这就违背了我们随时随地登录的原则。所以做了对应改动。代码中已直接改正。