I would like to check if a certain file exists on the remote host.
I tried this:
$ if [ ssh user#localhost -p 19999 -e /home/user/Dropbox/path/Research_and_Development/Puffer_and_Traps/Repeaters_Network/UBC_LOGS/log1349544129.tar.bz2 ] then echo "okidoke"; else "not okay!" fi
-sh: syntax error: unexpected "else" (expecting "then")
In addition to the answers above, there's the shorthand way to do it:
ssh -q $HOST [[ -f $FILE_PATH ]] && echo "File exists" || echo "File does not exist";
-q is quiet mode, it will suppress warnings and messages.
As #Mat mentioned, one advantage of testing like this is that you can easily swap out the -f for any test operator you like: -nt, -d, -s etc...
Test Operators: http://tldp.org/LDP/abs/html/fto.html
Here is a simple approach:
#!/bin/bash
USE_IP='-o StrictHostKeyChecking=no username#192.168.1.2'
FILE_NAME=/home/user/file.txt
SSH_PASS='sshpass -p password-for-remote-machine'
if $SSH_PASS ssh $USE_IP stat $FILE_NAME \> /dev/null 2\>\&1
then
echo "File exists"
else
echo "File does not exist"
fi
You need to install sshpass on your machine to work it.
Can't get much simpler than this :)
ssh host "test -e /path/to/file"
if [ $? -eq 0 ]; then
# your file exists
fi
As suggested by dimo414, this can be collapsed to:
if ssh host "test -e /path/to/file"; then
# your file exists
fi
one line, proper quoting
ssh remote_host test -f "/path/to/file" && echo found || echo not found
You're missing ;s. The general syntax if you put it all in one line would be:
if thing ; then ... ; else ... ; fi
The thing can be pretty much anything that returns an exit code. The then branch is taken if that thing returns 0, the else branch otherwise.
[ isn't syntax, it's the test program (check out ls /bin/[, it actually exists, man test for the docs – although can also have a built-in version with different/additional features.) which is used to test various common conditions on files and variables. (Note that [[ on the other hand is syntax and is handled by your shell, if it supports it).
For your case, you don't want to use test directly, you want to test something on the remote host. So try something like:
if ssh user#host test -e "$file" ; then ... ; else ... ; fi
Test if a file exists:
HOST="example.com"
FILE="/path/to/file"
if ssh $HOST "test -e $FILE"; then
echo "File exists."
else
echo "File does not exist."
fi
And the opposite, test if a file does not exist:
HOST="example.com"
FILE="/path/to/file"
if ! ssh $HOST "test -e $FILE"; then
echo "File does not exist."
else
echo "File exists."
fi
ssh -q $HOST [[ -f $FILE_PATH ]] && echo "File exists"
The above will run the echo command on the machine you're running the ssh command from. To get the remote server to run the command:
ssh -q $HOST "[[ ! -f $FILE_PATH ]] && touch $FILE_PATH"
Silent check if file exist and perform if not
if ! ssh $USER#$HOST "test -e file.txt" 2> /dev/null; then
echo "File not exist"
fi
You can specify the shell to be used by the remote host locally.
echo 'echo "Bash version: ${BASH_VERSION}"' | ssh -q localhost bash
And be careful to (single-)quote the variables you wish to be expanded by the remote host; otherwise variable expansion will be done by your local shell!
# example for local / remote variable expansion
{
echo "[[ $- == *i* ]] && echo 'Interactive' || echo 'Not interactive'" |
ssh -q localhost bash
echo '[[ $- == *i* ]] && echo "Interactive" || echo "Not interactive"' |
ssh -q localhost bash
}
So, to check if a certain file exists on the remote host you can do the following:
host='localhost' # localhost as test case
file='~/.bash_history'
if `echo 'test -f '"${file}"' && exit 0 || exit 1' | ssh -q "${host}" sh`; then
#if `echo '[[ -f '"${file}"' ]] && exit 0 || exit 1' | ssh -q "${host}" bash`; then
echo exists
else
echo does not exist
fi
I wanted also to check if a remote file exist but with RSH. I have tried the previous solutions but they didn't work with RSH.
Finally, I did I short function which works fine:
function existRemoteFile ()
{
REMOTE=$1
FILE=$2
RESULT=$(rsh -l user $REMOTE "test -e $FILE && echo \"0\" || echo \"1\"")
if [ $RESULT -eq 0 ]
then
return 0
else
return 1
fi
}
On CentOS machine, the oneliner bash that worked for me was:
if ssh <servername> "stat <filename> > /dev/null 2>&1"; then echo "file exists"; else echo "file doesnt exits"; fi
It needed I/O redirection (as the top answer) as well as quotes around the command to be run on remote.
This also works :
if ssh user#ip "[ -s /path/file_name ]" ;then
status=RECEIVED ;
else
status=MISSING ;
fi
#its simple
if [[ "`ssh -q user#hostname ls /dir/filename.abc 2>dev/null`" == "/dir/filename.abc" ]]
then
echo "file exists"
else
echo "file not exists"
fi
Related
When I set up a pre-receive server hook for GitLab project, it can work normally, but anyone and any role can directly push the code to this project protection branch (similar to master). When this custom hook is cancelled, the protection branch is normal again, and no one can push the code directly.
Does anyone know what's going on?
#!/usr/bin/env bash
export LANG="en_US.UTF-8"
REJECT=0
JAVA_HOME=/data/jdk1.8.0_144
CHECK_JAR_HOME=/opt/gitlab/embedded/service/gitaly-ruby/git-hooks/pre-receive.d
TEMPDIR="tmp_for_scan"
file_repository_path=`pwd`
sub_str=${file_repository_path%.git*}
repository_name=${sub_str##*/}
check_main() {
check
}
check() {
get_all_change_file_and_save
p3c_jar_check
rm -rf $TEMPDIR
if [[ $REJECT -ne 0 ]]; then
exit $REJECT
fi
}
p3c_jar_check() {
files_to_check=`find $TEMPDIR -name '*.java'`
if [[ -n $files_to_check && $files_to_check != "" ]];then
echo -e "ali-p3c-pmd check starting......"
$JAVA_HOME/bin/java -cp $CHECK_JAR_HOME/p3c-pmd-2.1.1.jar net.sourceforge.pmd.PMD -d $TEMPDIR -R rulesets/p3c.xml -f text -shortnames
REJECT=$?
echo -e "ali-p3c-pmd check end......"
if [[ $REJECT == 0 ]] ;then
echo -e "恭喜你代码通过质量检测!"
else
echo -e "请及时修改代码并再次尝试!!"
fi
else
echo 'ali-p3c-pmd pass....'
fi
}
get_all_change_file_and_save() {
while read oldrev newrev refname; do
if test "$oldrev" = "0000000000000000000000000000000000000000" ;then
oldrev="$newrev^"
fi
operate_log=`git log $oldrev..$newrev --pretty="%h $refname %B"`
if [[ $operate_log =~ "merge request" ]];then
echo "***merge request** continue"
continue
fi
files=`git diff --name-only $oldrev $newrev | grep -e ".java$"`
file_repository_path=`pwd`
if test -n "$files"; then
for file in $files; do
mkdir -p "$TEMPDIR/`dirname $file`" > /dev/null
git show $newrev:$file > $TEMPDIR/$file
done;
fi
break
done
}
check_main
exit $REJECT;
Double-check exactly how you have set up your hook, by reviewing "Chained hooks":
Server hooks are searched for and executed in the following order of priority:
Built-in GitLab server hooks. These are not user-customizable.
<project>.git/custom_hooks/<hook_name>: Per-project hooks. This was kept for backwards compatibility.
<project>.git/custom_hooks/<hook_name>.d/*: Location for per-project hooks.
<custom_hooks_dir>/<hook_name>.d/*: Location for all executable global hook files except editor backup files.
The goal is to make sure you do not override the default pre-receive hook, which is reserved for branch protection.
I am a beginner in bash scripting and I have created a bash script to add users and remove users on Linux. But since I am facing some issues with the script not really major issues but would be helpful if anyone could point me how to improve the script and the worst practice I am doing the script would be helpful
however the problem I have noticed is that the script takes -a to add a user -d to remove user and -h to get help the -a flag as 2 optional arguments -p for password and -s for shell so the command would be
./useradd.sh -a user -p password -s shell
this works as expected and the user is added to the system but the problem I am facing is that if I do not enter -a flag and specify the -s and -p flag the script is just exited I want to show a clear idea to the user why it exited and there is so many such errors I am assuming but I have not tested it out so much any help would be appreciated, so here is my script
#!/bin/bash
## checking if the user is privileged or not
if [[ $EUID != 0 ]]
then
echo "Script has to be ran as root or sudo"
echo "Aborting"
exit 101
fi
## creating help functions
function usage() {
echo "usage: ${0} -a <user> -p <password> -s <shell> | ${0} -d <user> | ${0} -h"
}
function help() {
echo "$0 - Script to add of remove users"
echo "-a - Add a new user"
echo " -p - Set password while creating user if not mentioned will not set any password by default"
echo " -s - Set a shell for the user default is /bin/bash if none specified"
echo "-a - Remove a user"
echo "-h - Print this help text"
}
if [[ "$#" -lt "1" ]]; then
echo "Argument has to be provided see $0 -h"
fi
shell=/bin/bash
password=$(openssl rand -base64 32)
while getopts :a:d:h opt; do
case $opt in
a) user=$OPTARG
while getopts :p:s: test
do
case $test in
p) password=$OPTARG;;
s) shell=$OPTARG;;
/?) echo "The provided flag is not identified see $0 -h"
exit;;
:) echo "$OPTARG requires arguments see $0 -h"
exit;;
esac
done
if [[ "$1" != "-a" ]]
then
echo "You have to specify username using -a flag see $0 -h"
fi
useradd -m $user -s $shell
echo "$user":"$password" | chpasswd
echo "The password for the $user is $password";;
d) userdel -f $OPTARG
if [[ $? == 0 ]]
then
echo "user has been removed"
else
echo "There was some error removing the user"
fi;;
h) help
exit;;
/?) echo "$OPTARG option not valid";;
:) echo "$OPTARG requires argument";;
esac
done
Please show your code! I usually process args with case ... in likes :
#!/bin/bash
while [[ $# -gt 0 ]]; do
case $1 in
"-a")
echo "-a is $2"
shift 2;;
"-d")
echo "-d is $2"
shift 2;;
esac
done
I am trying to create a script to create virtual clusters on my virtual machine which is a CentOS 7 minimal.
I got a script named cluster
#!/bin/bash
function vc
{
echo
echo -n "Enter project name: "
read platform_name
echo
echo -n "web extension: "
read web_extension
echo
echo -e "The following website will be created"
echo -e "\e[32m Platform:\e[0m\t${platform_name}"
echo -e "\e[32m Extension:\e[0m\t${web_extension}"
echo -e "\e[32m Full URL:\e[0m\t http://www.${platform_name}.${web_extension}"
echo
echo -e "Do you wish to proceed? [Y/n]"
read -p "Are you sure? " -n 1 -r
echo # (optional) move to a new line
if [[ $REPLY =~ ^[Yy]$ ]]
then
echo
echo -e "\e[32m Creating platform \e[0m\t"
else
echo
echo -e "\e[32m Not creating platform \e[0m\t"
fi
}
if [ -n "$(type -t $FUNCTION_NAME)" ] && [ "$(type -t $FUNCTION_NAME)" =
function ];
then $FUNCTION_NAME $2; else help; fi
Then as far as I understood I just have to make it executable
chmod +x cluster
And after this I should make a syslink for it ln -s cluster /bin/cluster
And now I should normally be able to just typ cluster vc in the terminal and it should execute the script but it keeps giving me "command cluster not found"
Am I doing something obviously wrong? Or do I need to use another chmod on it so I can run this?
Symbolic link targets are resolved relative the the symlink location. In your case that means, if you run /bin/cluster it looks for a file named cluster (the target) in the /bin/directory. Either provide a relative path which points to your file or link to an absolute path: ln -s /path/to/cluster /bin/cluster.
Also make sure that the target location is readable and executable by whomever executes the symlink.
I'm trying to run programs (for example mv file1.txt file2.txt) in my .sh script and I need to hide errors, but handle it with my script.
Currently I'm trying to do something like
EXECUTE="mv -v $VOL $BACKUP_YESTERDAY_CRYPT"
{
EXEC_ERROR=$($EXECUTE)
} &2>> $LOG_FILE
if [[ -n $EXEC_ERROR ]]; then
echo "There is an error!"
fi
But it doesn't work at all - it shows an error (for example mv: cannot stat 'file1.txt': No such file or directory) and $EXEC_ERROR variable is empty.
Is there any way to get output to variable + to log file?
How about something like:
mv -v $VOL $BACKUP_YESTERDAY_CRYPT 2>> $LOG_FILE
if [[ ! ( $? -eq 0 ) ]] ; then
echo "There is an error\!"
fi
Though $? is good for saving and processing exit codes, the if statement is designed to take any command, not just [ or [[:
if ! mv -v "$VOL" "$BACKUP_YESTERDAY_CRYPT" 2>> $LOG_FILE; then
echo "There is an error!"
fi
This includes saving variables:
if OUTPUT=$(mv -v "$VOL" "$BACKUP_YESTERDAY_CRYPT" 2>> $LOG_FILE); then
echo ">>> $OUTPUT <<<"
fi
In fact, if can take more than one command, as its man page describes. Documentation on boolean operators such as !, &&, and || is hidden within the description of shell commands, where they form pipelines (!) and lists (&&, ||).
Try this:
mv sourcefile destfile 2> /dev/null 1>logfile
returnstatus=`echo $?`
if [[ $returnstatus -ne 0 ]]; then
echo "There was an error!"
fi
I'm trying to create a script that searches through a directory to find symlinks that point to non-existing objects.
I have a file in a directory with a deleted symlink, but for some reason when i run the below script It says file exists.
#!/bin/bash
ls -l $1 |
if [ -d $1 ]
then
while read file
do
if test -e $1
then
echo "file exists"
else
echo "file does not exist"
fi
done
else
echo "No directory given"
fi
Thanks
Check this page. It has a test for broken links. It uses the -h operator to identify a symlink and the -e operator to check existance.
From that page:
linkchk () {
for element in $1/*; do
[ -h "$element" -a ! -e "$element" ] && echo \"$element\"
[ -d "$element" ] && linkchk $element
# Of course, '-h' tests for symbolic link, '-d' for directory.
done
}
# Send each arg that was passed to the script to the linkchk() function
#+ if it is a valid directoy. If not, then print the error message
#+ and usage info.
##################
for directory in $directorys; do
if [ -d $directory ]
then linkchk $directory
else
echo "$directory is not a directory"
echo "Usage: $0 dir1 dir2 ..."
fi
done
exit $?
You can test whether link is valid or not using:
[[ -f "$link" ]] && echo "points to a valid file"
To check if it is indeed a link use -L:
[[ -L "$link" ]] && echo "it's a link"
There seems to be a program named symlinks that does, among other things, what you're looking for.