Linux Shell腳本生產環境下安全地刪除文件
阿新 • • 發佈：2017-06-29
rm safe
腳本編寫背景
無論是生產環境、測試環境還是開發環境，經常需要使用rm命令刪除&批量一些“重要”目錄下的文件。按照Linux的哲學“小即是美”（一個程序只做一件事）+“用戶清楚自己做什麽”（用戶知道自己想要什麽，也明白自己在做什麽，並且會為自己的行為負責），那麽用戶在執行rm時，一定要知道自己的操作可能引起的後果，因此“三思而後行”真的很重要。但這對於一部分人來講，真的可能是災難性的，手抖、手賤和任何錯誤的操作（在路徑分隔符"/"前多打了空格，錯誤使用*，錯誤的路徑（當前路徑、相對路徑、錯誤的操作路徑）、錯誤腳本（竟然有人敢在生產環境調試未經過測試的腳本）、錯誤的批量操作、錯誤的安全策略）都可能引起數據的丟失，這在生產環境，特別是缺少備份缺少熱備的生產環境中是非常致命非常可怕的。
因此通過腳本或者其他方式來讓用戶後悔一次是非常有必要的。本文用Bash Shell Script的方式實現這一問題，其他解決方案可以參見文末的“參考”。
腳本編寫思路
跟回收站的思路比較相似，回收站有這樣的特性：1.並非真的刪除；2.同名的可以；3.記住文件的源路徑，作為腳本也應該做到如此
腳本使用起來應該跟rm使用起來基本類似
腳本使用截圖
關於rm的參數問題
腳本內使用忽略的策略，無論使用rm的哪種參數，都將進行mv操作，此處宜當改進。
腳本內容
腳本內容可以參見GitHub.
#!/usr/bin/env bash
# a command or alias to replace ‘rm‘ with a safe and easy to use, safe remove files or directories
# See also:
# safe-rm - wrapper around the rm command to prevent accidental deletions - https://github.com/kaelzhang/shell-safe-rm
# trash-cli - Command line interface to FreeDesktop.org Trash - https://pypi.python.org/pypi/trash-cli/
# debug option
DEBUG=false # DEBUG=true
if ${DEBUG} ; then
old_PS4=$PS4
# export PS4=‘+${BASH_SOURCE}:${LINENO}:${FUNCNAME[0]}: ‘
export PS4=‘+${LINENO}: ${FUNCNAME[0]}: ‘ # if there is only one bash script, do not display ${BASH_SOURCE}
_XTRACE_FUNCTIONS=$(set +o | grep xtrace)
set -o xtrace
fi
# set an empty function using for location this line quickly in PyCharm editor on purpose.
function _empty() { return; }
# Public header
# =============================================================================================================================
# resolve links - $0 may be a symbolic link
# learn from apache-tomcat-6.x.xx/bin/catalina.sh
PRG="$0"
while [ -h "$PRG" ]; do
ls=`ls -ld "$PRG"`
link=`expr "$ls" : ‘.*-> \(.*\)$‘`
if expr "$link" : ‘/.*‘ > /dev/null; then
PRG="$link"
else
PRG=`dirname "$PRG"`/"$link"
fi
done
# Get standard environment variables
PRGDIR=`dirname "$PRG"`
# echo color function, smarter, learn from lnmp.org lnmp install.sh
function echo_r (){
# Color red: Error, Failed
[ $# -ne 1 ] && return 1
echo -e "\033[31m$1\033[0m"
}
function echo_g (){
# Color green: Success
[ $# -ne 1 ] && return 1
echo -e "\033[32m$1\033[0m"
}
function echo_y (){
# Color yellow: Warning
[ $# -ne 1 ] && return 1
echo -e "\033[33m$1\033[0m"
}
function echo_b (){
# Color blue: Debug Level 1
[ $# -ne 1 ] && return 1
echo -e "\033[34m$1\033[0m"
}
function echo_p (){
# Color purple,magenta: Debug Level 2
[ $# -ne 1 ] && return 1
echo -e "\033[35m$1\033[0m"
}
function echo_c (){
# Color cyan: friendly prompt, Level 1
[ $# -ne 1 ] && return 1
echo -e "\033[36m$1\033[0m"
}
# end echo color function, smarter
#WORKDIR="`realpath ${WORKDIR}`"
WORKDIR="`readlink -f ${PRGDIR}`"
# end public header
# =============================================================================================================================
real_rm=‘/bin/rm‘
trash_dir="$HOME/.trash" # if do not use "$HOME" or "~" to resolve permission problem, should use "chmod o+t $trash_dir" .chmod --help: Each MODE is of the form `[ugoa]*([-+=]([rwxXst]*|[ugo]))+‘.
log_dir="$trash_dir"
log_file="$log_dir/operation.log"
trash_save_days=3
function real_rm() {
if [[ ! -f ${real_rm} ]]; then
echo ‘safe-rm cannot find the real "rm" binary‘
exit 1
fi
save_days=${trash_save_days:-10}
test $(find -L /tmp/.delete/ -type d ! -name "^." -a ! -wholename "/tmp/.delete/" -mtime +${save_days} -exec echo ‘{}‘ \; | wc -l ) -gt 0
found_old_files=$?
if [[ ${found_old_files} -eq 0 ]]; then
echo_b "old files found, cleaning"
#find -L ${trash_dir}/ -maxdepth 1 -type d ! -name "^." -mtime +${save_days} -exec rm -rf ‘{}‘ \;
find -L ${trash_dir}/ -maxdepth 1 -type d ! -wholename "$trash_dir/" ! -name "^." -mtime +${save_days} -exec rm -rf ‘{}‘ \;
echo_g "old files cleaned successfully"
else
echo_g "old files in standby state, passed"
fi
}
function safe_rm() {
if [[ "$1x" = ‘x‘ ]]; then
${real_rm} --help
exit 1
fi
if [[ ! -d ${trash_dir} ]]; then
mkdir -p ${trash_dir}
fi
# date +%Y%m%d%H%M%S.%N | shasum | awk ‘{print $1}‘ | cat - -A
uniq_trash_dir="$trash_dir/$(date +%Y%m%d%H%M%S.%N | shasum | awk ‘{print $1}‘)"
mkdir -p ${uniq_trash_dir}
if [[ $# -eq 1 ]];then
if [[ -f $1 ]] || [[ -d $1 ]]; then # ignore rm -f|-r|-rf|-fr, etc
mv $1 ${uniq_trash_dir}
retval=$?
fi
else
# alternative impl of ‘rm FILE...‘
parameter_array="$@"
# IFS=‘ ‘$‘\t‘$‘\n‘, IFS=$‘ \t\n‘, If IFS is unset, or its value is exactly <space><tab><newline>
old_IFS=$IFS
IFS=‘ ‘$‘\t‘$‘\n‘
for parameter in ${parameter_array}; do
if [[ -f ${parameter} ]] || [[ -d ${parameter} ]]; then # ignore rm -f|-r|-rf|-fr, etc
mv ${parameter} ${uniq_trash_dir}
fi
done
retval=$?
IFS="$old_IFS"
fi
log_operation $@
exit ${retval}
}
function log_operation(){
tee -a ${log_file}<<-eof # debug purpose or notify mode
{
"date_human": "$(date +‘%Y-%m-%d %H:%M:%S.%N‘)",
"date": "$(date)",
"user": "$USER",
"ssh_client": "$SSH_CLIENT",
"ssh_connection": "$SSH_CONNECTION",
"ssh_tty": "$SSH_TTY",
"trash_dir": "${uniq_trash_dir}"
"log_file":"${log_file}",
"pwd": "$PWD",
"operation": "$0 $@",
"parameter": "$@"
}
eof
}
function usage(){
cat - << eof
${WORKDIR}/`basename $0` help show help message
${WORKDIR}/`basename $0` clean clean old deleted files
eof
}
function main(){
lock_filename="lock_$$_${RANDOM}"
# lock_filename_full_path="/var/lock/subsys/$lock_filename"
lock_filename_full_path="/var/lock/$lock_filename"
if ( set -o noclobber; echo "$$" > "$lock_filename_full_path") 2> /dev/null;then
trap ‘rm -f "$lock_filename_full_path"; exit $?‘ INT TERM EXIT
[ ! -x ${WORKDIR}/`basename $0` ] && chmod +x ${WORKDIR}/`basename $0`
if [[ $# -lt 1 ]]; then
${WORKDIR}/`basename $0` help
exit 0
fi
if [ -f $1 ]; then
safe_rm $@
else
parameter_array="$@"
# IFS=‘ ‘$‘\t‘$‘\n‘, IFS=$‘ \t\n‘, If IFS is unset, or its value is exactly <space><tab><newline>
old_IFS=$IFS
IFS=‘ ‘$‘\t‘$‘\n‘
for parameter in ${parameter_array}; do
if [[ -f ${parameter} ]] || [[ -d ${parameter} ]]; then # ignore rm -f|-r|-rf|-fr, etc
safe_rm $@
fi
done
IFS="$old_IFS"
fi
case $1 in
clean)
real_rm
;;
help|*)
usage
exit 1
;;
esac
rm -f "$lock_filename_full_path"
trap - INT TERM EXIT
else
echo "Failed to acquire lock: $lock_filename_full_path"
echo "held by $(cat ${lock_filename_full_path})"
fi
}
main $@
# debug option
if ${DEBUG} ; then
export PS4=${old_PS4}
${_XTRACE_FUNCTIONS}
fi可以繼續做的事情
1.根據操作日誌方便的列出刪除的文件
2.根據操作日誌更方便的恢復文件
3.處理好文件不存在的情況
4.增加直接刪除的情況
5.保留權限的問題
6.從log_file中的operation和parameter中去除-rf這樣的參數
參考：
這種事別人早就有做好的了，雖然學習的過程需要積累和歷練，但人生苦短，有時也需要站在巨人的肩膀上。
《防止rm誤操作的方法》
《更改rm命令為移動到回收站》
《trash-cli 0.17.1.14》將rm變成移動到回收站的Python實現
tag:safe-rm,trash-cli,rm
--end--
本文出自 “通信，我的最愛” 博客，請務必保留此出處http://dgd2010.blog.51cto.com/1539422/1943170
Linux Shell腳本生產環境下安全地刪除文件