(Ubuntu bash script) Setting rights from a config txt - bash

I am a beginner and trying to write a script that takes a config file (example below) and sets the rights for the users, if that user or group doesn´t exist, they get added.
For every line in the file, I am cutting out the user or the group and check if they exist.
Right now I only check for users.
#!/bin/bash
function SetRights()
{
if [[ $# -eq 1 && -f $1 ]]
then
for line in $1
do
var1=$(cut -d: -f2 $line)
var2=$(cat /etc/passwd | grep $var1 | wc -l)
if [[ $var2 -eq 0 ]]
then
sudo useradd $var1
else
setfacl -m $line
fi
done
else
echo Enter the correct path of the configuration file.
fi
}
SetRights $1
The config file looks like this:
u:TestUser:- /home/temp
g:TestGroup:rw /home/temp/testFolder
u:TestUser2:r /home/temp/1234.txt
The output:
grep: TestGroup: No such file or directory
grep: TestUser: No such file or directory
"The useradd help menu"
If you could give me a hint what I should look for in my research, I would be very grateful.
Is it possible to reset var1 and var2? Using unset didn´t work for me and I couldn´t find variables could only be set once.

It's not clear how you are looping over the contents of the file -- if $1 contains the file name, you should not be seeing the errors you report.
But anyway, here is a refactored version which hopefully avoids your problems.
# Avoid Bash-only syntax for function definition
SetRights() {
# Indent function body
# Properly quote "$1"
if [[ $# -eq 1 && -f "$1" ]]
then
# Read lines in file
while read -r acl file
do
# Parse out user
user=${acl#*:}
user=${user%:*}
# Avoid useless use of cat
# Anchor regex correctly
if ! grep -q "^$user:" /etc/passwd
then
# Quote user
sudo useradd "$user"
else
setfacl -m "$acl" "$file"
fi
done <"$1"
else
# Error message to stderr
echo Enter the correct path of the configuration file. >&2
# Signal failure to the caller
return 1
fi
}
# Properly quote argument
SetRights "$1"

Related

Bash script to download from google images

Some weeks ago I found in this site a very useful bash script that downloads images from google image results (download images from google with command line)
Although the script is quite complicate for me, I did some simple modifications so as not to rename the results so as to keep the original names.
However, since the last week, the script stopped working... probably Google updated the code or something, and the regexes of the script don't parse the results any more. I don't know enough about google's codes, web programing or regexing to see what is wrong, although I did some educated guesses, but still didn't work.
My (unworking) tweaked script is this
#! /bin/bash
# function to create all dirs til file can be made
function mkdirs {
file="$1"
dir="/"
# convert to full path
if [ "${file##/*}" ]; then
file="${PWD}/${file}"
fi
# dir name of following dir
next="${file#/}"
# while not filename
while [ "${next//[^\/]/}" ]; do
# create dir if doesn't exist
[ -d "${dir}" ] || mkdir "${dir}"
dir="${dir}/${next%%/*}"
next="${next#*/}"
done
# last directory to make
[ -d "${dir}" ] || mkdir "${dir}"
}
# get optional 'o' flag, this will open the image after download
getopts 'o' option
[[ $option = 'o' ]] && shift
# parse arguments
count=${1}
shift
query="$#"
[ -z "$query" ] && exit 1 # insufficient arguments
# set user agent, customize this by visiting http://whatsmyuseragent.com/
useragent='Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:31.0) Gecko/20100101 Firefox/31.0'
# construct google link
link="www.google.cz/search?q=${query}\&tbm=isch"
# fetch link for download
imagelink=$(wget -e robots=off --user-agent "$useragent" -qO - "$link" | sed 's/</\n</g' | grep '<a href.*\(png\|jpg\|jpeg\)' | sed 's/.*imgurl=\([^&]*\)\&.*/\1/' | head -n $count | tail -n1)
imagelink="${imagelink%\%*}"
# get file extention (.png, .jpg, .jpeg)
ext=$(echo $imagelink | sed "s/.*\(\.[^\.]*\)$/\1/")
# set default save location and file name change this!!
dir="$PWD"
file="google image"
# get optional second argument, which defines the file name or dir
if [[ $# -eq 2 ]]; then
if [ -d "$2" ]; then
dir="$2"
else
file="${2}"
mkdirs "${dir}"
dir=""
fi
fi
# construct image link: add 'echo "${google_image}"'
# after this line for debug output
google_image="${dir}/${file}"
# construct name, append number if file exists
if [[ -e "${google_image}${ext}" ]] ; then
i=0
while [[ -e "${google_image}(${i})${ext}" ]] ; do
((i++))
done
google_image="${google_image}(${i})${ext}"
else
google_image="${google_image}${ext}"
fi
# get actual picture and store in google_image.$ext
wget --max-redirect 0 -q "${imagelink}"
# if 'o' flag supplied: open image
[[ $option = "o" ]] && gnome-open "${google_image}"
# successful execution, exit code 0
exit 0
one way to invetigate : provide -x option to bash so to have the trace of your script; that is change /bin/bash to /bin/bash -x in your script -or- simply invoke your script with
bash -x <yourscript>
You can also annotate your script with echo commands to track some variables.

Variable scope in Bash [duplicate]

Please explain to me why the very last echo statement is blank? I expect that XCODE is incremented in the while loop to a value of 1:
#!/bin/bash
OUTPUT="name1 ip ip status" # normally output of another command with multi line output
if [ -z "$OUTPUT" ]
then
echo "Status WARN: No messages from SMcli"
exit $STATE_WARNING
else
echo "$OUTPUT"|while read NAME IP1 IP2 STATUS
do
if [ "$STATUS" != "Optimal" ]
then
echo "CRIT: $NAME - $STATUS"
echo $((++XCODE))
else
echo "OK: $NAME - $STATUS"
fi
done
fi
echo $XCODE
I've tried using the following statement instead of the ++XCODE method
XCODE=`expr $XCODE + 1`
and it too won't print outside of the while statement. I think I'm missing something about variable scope here, but the ol' man page isn't showing it to me.
Because you're piping into the while loop, a sub-shell is created to run the while loop.
Now this child process has its own copy of the environment and can't pass any
variables back to its parent (as in any unix process).
Therefore you'll need to restructure so that you're not piping into the loop.
Alternatively you could run in a function, for example, and echo the value you
want returned from the sub-process.
http://tldp.org/LDP/abs/html/subshells.html#SUBSHELL
The problem is that processes put together with a pipe are executed in subshells (and therefore have their own environment). Whatever happens within the while does not affect anything outside of the pipe.
Your specific example can be solved by rewriting the pipe to
while ... do ... done <<< "$OUTPUT"
or perhaps
while ... do ... done < <(echo "$OUTPUT")
This should work as well (because echo and while are in same subshell):
#!/bin/bash
cat /tmp/randomFile | (while read line
do
LINE="$LINE $line"
done && echo $LINE )
One more option:
#!/bin/bash
cat /some/file | while read line
do
var="abc"
echo $var | xsel -i -p # redirect stdin to the X primary selection
done
var=$(xsel -o -p) # redirect back to stdout
echo $var
EDIT:
Here, xsel is a requirement (install it).
Alternatively, you can use xclip:
xclip -i -selection clipboard
instead of
xsel -i -p
I got around this when I was making my own little du:
ls -l | sed '/total/d ; s/ */\t/g' | cut -f 5 |
( SUM=0; while read SIZE; do SUM=$(($SUM+$SIZE)); done; echo "$(($SUM/1024/1024/1024))GB" )
The point is that I make a subshell with ( ) containing my SUM variable and the while, but I pipe into the whole ( ) instead of into the while itself, which avoids the gotcha.
#!/bin/bash
OUTPUT="name1 ip ip status"
+export XCODE=0;
if [ -z "$OUTPUT" ]
----
echo "CRIT: $NAME - $STATUS"
- echo $((++XCODE))
+ export XCODE=$(( $XCODE + 1 ))
else
echo $XCODE
see if those changes help
Another option is to output the results into a file from the subshell and then read it in the parent shell. something like
#!/bin/bash
EXPORTFILE=/tmp/exportfile${RANDOM}
cat /tmp/randomFile | while read line
do
LINE="$LINE $line"
echo $LINE > $EXPORTFILE
done
LINE=$(cat $EXPORTFILE)

Curl not downloading files correctly

So I have been struggling with this task for eternity and still don't get what went wrong. This program doesn't seem to download ANY pdfs. At the same time I checked the file that stores final links - everything stored correctly. The $PDFURL also checked, stores correct values. Any bash fans ready to help?
#!/bin/sh
#create a temporary directory where all the work will be conducted
TMPDIR=`mktemp -d /tmp/chiheisen.XXXXXXXXXX`
echo $TMPDIR
#no arguments given - error
if [ "$#" == "0" ]; then
exit 1
fi
# argument given, but wrong format
URL="$1"
#URL regex
URL_REG='(https?|ftp|file)://[-A-Za-z0-9\+&##/%?=~_|!:,.;]*[-A-Za-z0-9\+&##/%=~_|]'
if [[ ! $URL =~ $URL_REG ]]; then
exit 1
fi
# go to directory created
cd $TMPDIR
#download the html page
curl -s "$1" > htmlfile.html
#grep only links into temp.txt
cat htmlfile.html | grep -o -E 'href="([^"#]+)\.pdf"' | cut -d'"' -f2 > temp.txt
# iterate through lines in the file and try to download
# the pdf files that are there
cat temp.txt | while read PDFURL; do
#if this is an absolute URL, download the file directly
if [[ $PDFURL == *http* ]]
then
curl -s -f -O $PDFURL
err="$?"
if [ "$err" -ne 0 ]
then
echo ERROR "$(basename $PDFURL)">&2
else
echo "$(basename $PDFURL)"
fi
else
#update url - it is always relative to the first parameter in script
PDFURLU="$1""/""$(basename $PDFURL)"
curl -s -f -O $PDFURLU
err="$?"
if [ "$err" -ne 0 ]
then
echo ERROR "$(basename $PDFURLU)">&2
else
echo "$(basename $PDFURLU)"
fi
fi
done
#delete the files
rm htmlfile.html
rm temp.txt
P.S. Another minor problem I have just spotted. Maybe the problem is with the if in regex? I pretty much would like to see something like that there:
if [[ $PDFURL =~ (https?|ftp|file):// ]]
but this doesn't work. I don't have unwanted parentheses there, so why?
P.P.S. I also ran this script on URLs beginning with http, and the program gave the desired output. However, it still doesn't pass the test.

Check if bash command has specified modificator

During the configuration of Symfony 2 project it is required to set appropriate privilages to the cache and log directories.
Documentation says to do it in two ways. One of them is calling setfacl command with -m modificator. However not every version contains this modificator. Is it possible to check if this command or any other command allows to set some modificator ?
For example with following pseudocode:
if [ checkmods --command=setfacl --modificator=-m ]
setfacl -m ....
else
chmod ...
You can parse the usage information by running setfacl --help and check if contains the modificator. For example:
if setfacl --help | grep -q -- -m,
then
echo "setfacl -m supported"
else
echo "setfacl -m not supported"
fi
If you want to do it for any command which has the --help option, take a look at the _parse_help function available in your bash-completion file.
http://anonscm.debian.org/gitweb/?p=bash-completion/bash-completion.git;a=blob;f=bash_completion
# Parse GNU style help output of the given command.
# #param $1 command; if "-", read from stdin and ignore rest of args
# #param $2 command options (default: --help)
#
_parse_help()
{
eval local cmd=$( quote "$1" )
local line
{ case $cmd in
-) cat ;;
*) LC_ALL=C "$( dequote "$cmd" )" ${2:---help} 2>&1 ;;
esac } \
| while read -r line; do
[[ $line == *([ $'\t'])-* ]] || continue
# transform "-f FOO, --foo=FOO" to "-f , --foo=FOO" etc
while [[ $line =~ \
((^|[^-])-[A-Za-z0-9?][[:space:]]+)\[?[A-Z0-9]+\]? ]]; do
line=${line/"${BASH_REMATCH[0]}"/"${BASH_REMATCH[1]}"}
done
__parse_options "${line// or /, }"
done
}

Bash variable scope

Please explain to me why the very last echo statement is blank? I expect that XCODE is incremented in the while loop to a value of 1:
#!/bin/bash
OUTPUT="name1 ip ip status" # normally output of another command with multi line output
if [ -z "$OUTPUT" ]
then
echo "Status WARN: No messages from SMcli"
exit $STATE_WARNING
else
echo "$OUTPUT"|while read NAME IP1 IP2 STATUS
do
if [ "$STATUS" != "Optimal" ]
then
echo "CRIT: $NAME - $STATUS"
echo $((++XCODE))
else
echo "OK: $NAME - $STATUS"
fi
done
fi
echo $XCODE
I've tried using the following statement instead of the ++XCODE method
XCODE=`expr $XCODE + 1`
and it too won't print outside of the while statement. I think I'm missing something about variable scope here, but the ol' man page isn't showing it to me.
Because you're piping into the while loop, a sub-shell is created to run the while loop.
Now this child process has its own copy of the environment and can't pass any
variables back to its parent (as in any unix process).
Therefore you'll need to restructure so that you're not piping into the loop.
Alternatively you could run in a function, for example, and echo the value you
want returned from the sub-process.
http://tldp.org/LDP/abs/html/subshells.html#SUBSHELL
The problem is that processes put together with a pipe are executed in subshells (and therefore have their own environment). Whatever happens within the while does not affect anything outside of the pipe.
Your specific example can be solved by rewriting the pipe to
while ... do ... done <<< "$OUTPUT"
or perhaps
while ... do ... done < <(echo "$OUTPUT")
This should work as well (because echo and while are in same subshell):
#!/bin/bash
cat /tmp/randomFile | (while read line
do
LINE="$LINE $line"
done && echo $LINE )
One more option:
#!/bin/bash
cat /some/file | while read line
do
var="abc"
echo $var | xsel -i -p # redirect stdin to the X primary selection
done
var=$(xsel -o -p) # redirect back to stdout
echo $var
EDIT:
Here, xsel is a requirement (install it).
Alternatively, you can use xclip:
xclip -i -selection clipboard
instead of
xsel -i -p
I got around this when I was making my own little du:
ls -l | sed '/total/d ; s/ */\t/g' | cut -f 5 |
( SUM=0; while read SIZE; do SUM=$(($SUM+$SIZE)); done; echo "$(($SUM/1024/1024/1024))GB" )
The point is that I make a subshell with ( ) containing my SUM variable and the while, but I pipe into the whole ( ) instead of into the while itself, which avoids the gotcha.
#!/bin/bash
OUTPUT="name1 ip ip status"
+export XCODE=0;
if [ -z "$OUTPUT" ]
----
echo "CRIT: $NAME - $STATUS"
- echo $((++XCODE))
+ export XCODE=$(( $XCODE + 1 ))
else
echo $XCODE
see if those changes help
Another option is to output the results into a file from the subshell and then read it in the parent shell. something like
#!/bin/bash
EXPORTFILE=/tmp/exportfile${RANDOM}
cat /tmp/randomFile | while read line
do
LINE="$LINE $line"
echo $LINE > $EXPORTFILE
done
LINE=$(cat $EXPORTFILE)

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