I'm writing a BASH script to purge the cache from a web server. The script is designed to take arguments from positional parameters. "ShellCheck.net" is telling me that my script is functionally correct, but when I test it I'm getting error where I shouldn't ... so I thought I'd ask for some folks to put fresh eyes on it. Take a look, I'll continue below and describe my problem:
#!/bin/bash
#
# Verify the user running is root, if not, fail.
if [[ "$UID" -ne "0" ]]; #added-1438279711
then
echo 'Only ROOT may run this script.';
exit 1;
fi
#
# Set the variables
BASE="/path/to/folder/foo/bar/" #added-1438279711
DOMAINOPT="$1" #added 1438451428
PATHOPT="$2" #added 1438451428
#
# Define Functions
function usage() { #added-1438382631
echo -en "Proper Usage:\n\n"
echo -en "\tSpecify the domain to be used\n"
echo -en "\tUsage: \"cleancache.sh abc.com\"\n"
echo -en "\t\tNote: This option will search for files and folders, recursively, within the domain folder, and remove them.\n\n"
echo -en "\tSpecify the URI you'd like to act upon within the domain\n"
echo -en "\tUsage: \"cleancache.sh abc.com /path/to/folder/\"\n"
echo -en "\t\tNote: This option will search for files and folders, recursively,\n\t\twithin the specified path, and remove them. Removing a single file is not currently supported with this script.\n\n"
}
#
# Validate the input
if [[ ! -z "$DOMAINOPT" ]] && [[ "$DOMAINOPT" != "^[A-Za-z0-9-]*[\.][a-z]*$" ]] #added-1438462778
then
clear
echo -en "Please follow the proper format for the DOMAIN option\n\n"
usage
exit 1
elif [[ ! -z "$DOMAINOPT" ]] && [[ "$DOMAINOPT" = "^[A-Za-z0-9-]*[\.][a-z]*$" ]]
then
DOMAINOPT="$DOMAINOPT"
else
clear
echo -en "Please enter a domain!\n\n"
usage
exit 1
fi
if [[ ! -z "$PATHOPT" ]] && [[ "$PATHOPT" != "^[\/][\S]*[\/]$" ]] #added-1438456371
then
clear
echo "Please follow the proper format for the PATH option"
usage
exit 1
elif [[ ! -z "$PATHOPT" ]] && [[ "$PATHOPT" = "^[\/][\S]*[\/]$" ]]
then
PATHOPT="$PATHOPT"
else
echo ""
fi
#
# Doing Stuff
if [[ "$#" -gt "2" ]]
then
echo -en "Too many arguments!\n\n"
usage
exit 1
elif [[ "$#" -eq "2" ]]
then
echo "Purging Cache in \"$BASE$DOMAINOPT$PATHOPT\""
find "$BASE""$DOMAINOPT""$PATHOPT" -type d -exec rm -rf {} \;
find "$BASE""$DOMAINOPT""$PATHOPT" -type f -exec rm -f {} \;
echo "Purging Complete"
exit 0
else
echo "Purging Cache in \"$BASE$DOMAINOPT\""
find "$BASE" -type d -name "$DOMAINOPT" -exec rm -rf {} \;
mkdir -p "$BASE$DOMAINOPT" && chown apache:apache "$BASE$DOMAINOPT" && chmod 755 "$BASE$DOMAINOPT"
echo "Purging Complete!"
echo "Creating \".stat\" file"
echo "" > "$BASE""$DOMAINOPT""/.stat"
if [[ -f "$BASE""$DOMAINOPT""/.stat" ]] #added-1438387045
then
echo "$BASE$DOMAINOPT/.stat file created!"
fi
fi
echo "All Operations Complete, exiting now!"
Everything responds normally if you run the script without any arguments (Please enter a domain), It responds normally if you try to enter a path before a domain ... but when I do it correctly, when I type: "cleancache.sh abc.com", I get an error like i haven't met the required pattern ("Please follow the proper format for the DOMAIN option") ... when that is exactly write! ... I don't understand what I'm missing, been banging my head all day, no joy.
PLEASE HELP!
Use this to match a regex:
[[ "$DOMAINOPT" =~ ^[A-Za-z0-9-]*[\.][a-z]*$ ]]
or this:
[[ ! "$DOMAINOPT" =~ ^[A-Za-z0-9-]*[\.][a-z]*$ ]]
Don't quote the regex.
Related
I am new to shell, and my code takes two arguments from the user. I would like to confirm their arguments before running the rest of the code. I would like a y for yes to prompt the code, and if they type n for no, then the code will ask again for new arguments
Pretty much, if i type anything when I am asked to confirm, the rest of the code runs anyways. I tried inserting the rest of the code after the first then statement, but that didn't work either. I have also checked my code with ShellCheck and it all appears to be legal syntax. Any advice?
#!/bin/bash
#user passes two arguments
echo "Enter source file name, and the number of copies: "
read -p "Your file name is $1 and the number of copies is $2. Press Y for yes N for no " -n 1 -r
echo
if [[ $REPLY =~ ^[Yy]$ ]]
then
echo "cloning files...."
fi
#----------------------------------------REST OF CODE
DIR="."
function list_files()
{
if ! test -d "$1"
then echo "$1"; return;
fi
cd ... || $1
echo; echo "$(pwd)":; #Display Directory name
for i in *
do
if test -d "$i" #if dictionary
then
list_files "$i" #recursively list files
cd ..
else
echo "$i"; #Display File name
fi
done
}
if [ $# -eq 0 ]
then list_files .
exit 0
fi
for i in "$#*"
do
DIR=$1
list_files "$DIR"
shift 1 #To read next directory/file name
done
if [ ! -f "$1" ]
then
echo "File $1 does not exist"
exit 1
fi
for ((i=0; i<$2; i++))
do
cp "$1" "$1$i.txt"; #copies the file i amount of times, and creates new files with names that increment by 1
done
status=$?
if [ "$status" -eq 0 ]
then
echo 'File copied succeaful'
else
echo 'Problem copying'
fi
Moving the prompts into a while loop might help here. The loop will re-prompt for the values until the user confirms them. Upon confirmation, the target code will be executed and the break statement will terminate the loop.
while :
do
echo "Enter source file name:"
read source_file
echo "Number of copies"
read number_of_copies
echo "Your file name is $source_file and the number of copies is $number_of_copies."
read -p "Press Y for yes N for no " -n 1 -r
if [[ $REPLY =~ ^[Yy]$ ]]; then
echo "cloning files...."
break ### <<<---- terminate the loop
fi
echo ""
done
#----------------------------------------REST OF CODE
I have a script which really needs an rm -fr on a specific folder
I'd like to make this as safe as possible. I started this script below but I was wondering if there's anything else I missed.
folder=""
if [[ ! -d "$folder" ]]; then
echo "Error: is not a folder"
elif [[ "$folder" == "/" ]]; then
echo "Error: folder points to root"
elif [[ "$folder" == "../"* ]]; then
echo "Error: folder start with ../"
elif [[ "$folder" == *"/.."* ]]; then
echo "Error: folder contains /.."
elif [[ "$folder" == *"/*"* ]]; then
echo "Error: folder ends with /*"
else
rm -fr "$folder"
fi
Update: added the check for "/"
If you want to be as safe as possible, you could perhaps...
Make sure any globbing is done first :
shopt -s nullglob
declare -a folders=(folder_or_glob)
Iterate over each element of the array, one at a time, and operate on the canonical path.
for f in "${folders[#]-}"
do
[[ $f ]] || continue
candidate="$(realpath -e -s "$f")" || continue
ok_to_delete "$candidate" || continue
rm -rf "$candidate"
done
Use function ok_to_delete to test :
ok_to_delete()
{
[[ -d $1 ]] || continue # Is directory
[[ $1 != / ]] || continue # Not root
[[ "${1%/*}" ]] || continue # At least two levels deep
(... add any test you want ...)
}
There is a bit of redundancy here (e.g. not root + 2 levels deep), but this is just to give you ideas.
Instead of checking the path name of folder, I would rather to check the contents in that folder, file's size/user/timestamp/keywork/extension, etc, or whatever you care most about. This is a more safe method for you, this's just my two cents.
I have a bash script which is intended to be idempotent. It creates symlinks, and it should be okay if the links are already there.
Here's an extract
L="/var/me/foo"
if [[ -e "$L" ]] && ! [[ -L "$L" ]];
then
echo "$L exists but is not a link."
exit 1;
elif [[ -e "$L" ]] && [[ -L "$L" ]];
then
echo "$L exists and is a link."
else
ln -s "/other/place" "$L" ||
{
echo "Could not chown ln -s for $L";
exit 1;
}
fi
The file /var/me/foo is already a symlink pointing to /other/place, according to ls -l.
Nevertheless, when I run this script the if and elif branches are not entered, instead we go into the else and attempt the ln, which fails because the file already exists.
Why do my tests not work?
Because you only check [ -L "$L" ] if [ -e "$L" ] is true, and [ -e "$L" ] returns false for a link pointing to a destination that doesn't exist, you don't detect links that point to locations that don't exist.
The below logic is a bit more comprehensive.
link=/var/me/foo
dest=/other/place
# because [[ ]] is in use, quotes are not mandatory
if [[ -L $link ]]; then
echo "$link exists as a link, though its target may or may not exist" >&2
elif [[ -e $link ]]; then
echo "$link exists but is not a link" >&2
exit 1
else
ln -s "$dest" "$link" || { echo "yadda yadda" >&2; exit 1; }
fi
for var in "$#"
do
if test -z $var
then
echo "missing operand"
elif [ -d $var ]
then
echo "This is a directory"
elif [ ! -f $var ]
then
echo "The file does not exist"
else
basename=$(basename $var)
dirname=$(readlink -f $var)
inodeno=$(ls -i $var| cut -d" " -f1)
read -p "remove regular file $#" input
if [ $input = "n" ]
then exit 1
fi
mv $var "$var"_"$inodeno"
echo "$basename"_"$inodeno":"$dirname" >> $HOME/.restore.info
mv "$var"_"$inodeno" $HOME/deleted
fi
done
**Hello, the above code is trying to mimic the rm command in unix. Its purpose is to remove the file .
Eg if I type in bash safe_rm file1 , it works however if type in
bash safe_rm file1 file 2 , it prompts me to remove file 1 twice and gives me a unary operater expected for line 27(if [ $input = "n" ]).
Why does it not work for two files, ideally I would like it to prompt me to remove file1 and file 2.
Thanks
read -p "remove regular file $#" input
should probably be
read -p "remove regular file $var" input
That's the basic.
And this is how I'd prefer to do it:
for T in "$#"; do
if [[ -z $T ]]; then
echo "Target is null."
elif [[ ! -e $T ]]; then
echo "Target does not exist: $T"
elif [[ -d $T ]]; then
echo "Target can't be a directory: $T"
else
BASE=${T##*/}
DIRNAME=$(exec dirname "$T") ## Could be simpler but not sure how you want to use it.
INODE_NUM=$(exec stat -c '%i' "$T")
read -p "Remove regular file $T? "
if [[ $REPLY == [yY] ]]; then
# Just copied. Not sure about its logic.
mv "$T" "${T}_${INODE_NUM}"
echo "${BASE}_${INODE_NUM}:${DIRNAME}" >> "$HOME/.restore.info"
mv "${T}_${INODE_NUM}" "$HOME/deleted"
fi
fi
done
EDITED: this is more or less what I came up after #Mechanical's nice input. Any insight?
#!/bin/bash
path1="$(readlink -e "$1")"
path2="$(readlink -e "$2")"
EBADARGS=65
function checkArgsNumber()
{
if test "$#" -ne 2; then
echo "ERRORE: this script takes exactly 2 params."
exit $EBADARGS
fi
}
function checkExistence()
{
if [ ! -d $path1 ]; then
echo "ERROR: "$1" does not exist"
exit $EBADARGS
elif [ ! -d "$2" ]; then
echo "ERROR: "$2" does not exist"
exit $EBADARGS
elif [[ -L $path1 ]]; then
echo "ERROR: path1 can't be a symbolic link"
exit $EBADARGS
elif [[ -L $2 ]]; then
echo "ERROR: path2 can't be a symbolic link"
exit $EBADARGS
fi
}
function checkIfSame()
{
if [[ $path1 == $path2 ]]; then
echo "ERROR: path1 and path2 must be different directories"
exit $EBADARGS
fi
}
function checkIfSubdirectories()
{
if [[ $path1 = *$path2* ]]; then
echo "ERROR:"$1" is a $path2 subdirectory"
exit $EBADARGS
elif [[ $path2 = *$path1* ]]; then
echo "ERROR:"$2" is a $path1 subdirectory"
exit $EBADARGS
elif [[ -e "$(find $path1 -samefile $path2)" ]]; then
echo "ERROR:"$(find $path1 -samefile $path2 -print0)" and "$2" have the same inode, $path2 is a $path1 subdirectory"
exit $EBADARGS
elif [[ -e "$(find $path2 -samefile $path1)" ]]; then
echo "ERROR:"$(find $path2 -samefile $path1 -print0)" and "$2" have the same inode, $path1 is a $path2 subdirectory"
exit $EBADARGS
fi
}
checkArgsNumber "$#"
checkExistence "$#"
checkIfSame "$#"
checkIfSubdirectories "$#"
now.. this should work and I hope it is useful somehow.
Could someone explain me how the *$path2* part works? What is the name of this * * operator? Where should I go read about it?
Some problems:
Stylistic
You should probably quote the entire argument to echo, as
echo "ERROR: $1 is a subdirectory of $(readlink -e "$2")"
Without the quotes around the argument to echo, you are technically passing each word as its own parameter: echo "ERROR:somedir" "is" "a" "subdirectory".... Since echo prints its parameters in the order given, separated by spaces, the output is the same in your case. But semantically it's not what you want.
(An example where it would be different:
echo foo bar
would print foo bar.)
Error message doesn't work properly
If the arguments don't exist
$ ./check.sh nonexistent1 nonexistent2
ERROR:nonexistent1 is a subdirectory of
Obviously, this is irrelevant if you've already checked they exist.
You similarly need to check for corner cases such as where the parameters refer to the same directory:
$ mkdir a b
$ ln -s ../a b/c
$ ./check.sh a b/c
ERROR:a is a subdirectory of /dev/shm/a
Doesn't detect symbolic links
$ mkdir a b
$ ln -s ../a b/c
$ ./check.sh a b
gives no error message.
Doesn't detect mount --bind
$ mkdir a b b/c
$ sudo mount --bind a b/c
$ ./check.sh a b
gives no error message.