Wait until zip fully written then continue, Bash Script - bash

I've been trying to zip a file and then upload it by FTP using a bash script, but it's uploading a corrupt zip file. I've had a look around and I'm trying to use lsof | grep to confirm the file is complete but I'm not really sure what I'm doing.
So I've got
cd /var/test/tobezipped
zip -r test.zip *
FOLDER="/var/test/tobezipped"
ZIPS=$(ls $FOLDER)
for F in $zips ; do
while [ -n "$(lsof | grep $F" ] ; do
sleep 1
done
ftp -n <<EOF
open myserver
user user pass
put test.zip
EOF
done
and test.zip is corrupt at the time it's being uploaded, so on the other server it's not readable but on the server it's zipped on it's all good by the time I check it.
Any kind of advice is appreciated, I'm pretty new to this sort of thing and tried to search around heaps to find a solution, not too sure I'm going in the right direction. Thanks in advance.

From the man page:
put local-file [remote-file]
Store a local file on the remote machine. If remote-file is left unspecified, the local file name is used after
processing according to
any ntrans or nmap settings in naming the remote file. File transfer uses the current settings for type, format, mode,
and structure.
I guess the problem is that you are not transfering files in BINARY mode.
Try this:
ftp -n <<EOF
open myserver
user user pass
binary
put test.zip
EOF

Try this.
PID=$(pgrep zip)
while [[ ( -d /proc/$PID) ) && ( -z `grep zombie /proc/$PID/status` ) ]]; do
sleep 1
done

Related

Extracting certain files from a tar archive on a remote ssh server

I am running numerous simulations on a remote server (via ssh). The outcomes of these simulations are stored as .tar archives in an archive directory on this remote server.
What I would like to do, is write a bash script which connects to the remote server via ssh and extracts the required output files from each .tar archive into separate folders on my local hard drive.
These folders should have the same name as the .tar file from which the files come (To give an example, say the output of simulation 1 is stored in the archive S1.tar on the remote server, I want all '.dat' and '.def' files within this .tar archive to be extracted to a directory S1 on my local drive).
For the extraction itself, I was trying:
for f in *.tar; do
(
mkdir ../${f%.tar}
tar -x -f "$f" -C ../${f%.tar} "*.dat" "*.def"
)
done
wait
Every .tar file is around 1GB and there is a lot of them. So downloading everything takes too much time, which is why I only want to extract the necessary files (see the extensions in the code above).
Now the code works perfectly when I have the .tar files on my local drive. However, what I can't figure out is how I can do it without first having to download all the .tar archives from the server.
When I first connect to the remote server via ssh username#host, then the terminal stops with the script and just connects to the server.
Btw I am doing this in VS Code and running the script through terminal on my MacBook.
I hope I have described it clear enough. Thanks for the help!
Stream the results of tar back with filenames via SSH
To get the data you wish to retrieve from .tar files, you'll need to pass the results of tar to a string of commands with the --to-command option. In the example below, we'll run three commands.
# Send the files name back to your shell
echo $TAR_FILENAME
# Send the contents of the file back
cat /dev/stdin
# Send EOF (Ctrl+d) back (note: since we're already in a $'' we don't use the $ again)
echo '\004'
Once the information is captured in your shell, we can start to process the data. This is a three-step process.
Get the file's name
note that, in this code, we aren't handling directories at all (simply stripping them away; i.e. dir/1.dat -> 1.dat)
you can write code to create directories for the file by replacing the forward slashes / with spaces and iterating over each directory name but that seems out-of-scope for this.
Check for the EOF (end-of-file)
Add content to file
# Get the files via ssh and tar
files=$(ssh -n <user#server> $'tar -xf <tar-file> --wildcards \'*\' --to-command=$\'echo $TAR_FILENAME; cat /dev/stdin; echo \'\004\'\'')
# Keeps track of what state we're in (filename or content)
state="filename"
filename=""
# Each line is one of these:
# - file's name
# - file's data
# - EOF
while read line; do
if [[ $state == "filename" ]]; then
filename=${line/*\//}
touch $filename
echo "Copying: $filename"
state="content"
elif [[ $state == "content" ]]; then
# look for EOF (ctrl+d)
if [[ $line == $'\004' ]]; then
filename=""
state="filename"
else
# append data to file
echo $line >> <output-folder>/$filename
fi
fi
# Double quotes here are very important
done < <(echo -e "$files")
Alternative: tar + scp
If the above example seems overly complex for what it's doing, it is. An alternative that touches the disk more and requires to separate ssh connections would be to extract the files you need from your .tar file to a folder and scp that folder back to your workstation.
ssh -n <username>#<server> 'mkdir output/; tar -C output/ -xf <tar-file> --wildcards *.dat *.def'
scp -r <username>#<server>:output/ ./
The breakdown
First, we'll make a place to keep our outputted files. You can skip this if you already know the folder they'll be in.
mkdir output/
Then, we'll extract the matching files to this folder we created (if you don't want them to be in a different folder remove the -C output/ option).
tar -C output/ -xf <tar-file> --wildcards *.dat *.def
Lastly, now that we're running commands on our machine again, we can run scp to reconnect to the remote machine and pull the files back.
scp -r <username>#<server>:output/ ./

Shell Script to redirect to different directory and create a list file

src_dir="/export/home/destination"
list_file="client_list_file.txt"
file=".csv"
echo "src directory="$src_dir
echo "list_file="$list_file
echo "file="$file
cd /export/home/destination
touch $list_file
x=`ls *$file | sort >$list_file`
if [ -s $list_file ]
then
echo "List File is available, archiving now"
y=`tar -cvf mystuff.tar $list_file`
else
echo "List File is not available"
fi
The above script is working fine and it's supposed to create a list file of all .csv files and tar's it.
However I am trying to do it from a different directory while running the script, so it should go to the destination directory and makes a list file with all the .csv in destination directory and make a .tar from the list file(i.e archive the list file)
So i am not sure what to change
there are a lot of tricks in filename handling. the one thing you should know is file naming under POSIX sucks. commands like ls or find may not return the expected result(but 99% of the time they will). so here is what you have to do to get the list of files truely:
for file in $src_dir/*.csv; do
echo `basename $file` >> $src_dir/$list_file
done
tar cvf $src_dir/mystuff.tar $src_dir/$list_file
maybe you should learn bash in a serious manner and try to google first before you asking question in SO next time.
http://www.gnu.org/software/bash/manual/html_node/index.html#SEC_Contents
http://tldp.org/HOWTO/Bash-Prog-Intro-HOWTO.html

Create a detailed self tracing log in bash

I know you can create a log of the output by typing in script nameOfLog.txt and exit in terminal before and after running the script, but I want to write it in the actual script so it creates a log automatically. There is a problem I'm having with the exec >>log_file 2>&1 line:
The code redirects the output to a log file and a user can no longer interact with it. How can I create a log where it just basically copies what is in the output?
And, is it possible to have it also automatically record the process of files that were copied? For example, if a file at /home/user/Deskop/file.sh was copied to /home/bckup, is it possible to have that printed in the log too or will I have to write that manually?
Is it also possible to record the amount of time it took to run the whole process and count the number of files and directories that were processed or am I going to have to write that manually too?
My future self appreciates all the help!
Here is my whole code:
#!/bin/bash
collect()
{
find "$directory" -name "*.sh" -print0 | xargs -0 cp -t ~/bckup #xargs handles files names with spaces. Also gives error of "cp: will not overwrite just-created" even if file didn't exist previously
}
echo "Starting log"
exec >>log_file 2>&1
timelimit=10
echo "Please enter the directory that you would like to collect.
If no input in 10 secs, default of /home will be selected"
read -t $timelimit directory
if [ ! -z "$directory" ] #if directory doesn't have a length of 0
then
echo -e "\nYou want to copy $directory." #-e is so the \n will work and it won't show up as part of the string
else
directory=/home/
echo "Time's up. Backup will be in $directory"
fi
if [ ! -d ~/bckup ]
then
echo "Directory does not exist, creating now"
mkdir ~/bckup
fi
collect
echo "Finished collecting"
exit 0
To answer the "how to just copy the output" question: use a program called tee and then a bit of exec magic explained here:
redirect COPY of stdout to log file from within bash script itself
Regarding the analytics (time needed, files accessed, etc) -- this is a bit harder. Some programs that can help you are time(1):
time - run programs and summarize system resource usage
and strace(1):
strace - trace system calls and signals
Check the man pages for more info. If you have control over the script it will be probably easier to do the logging yourself instead of parsing strace output.

bash: check if remote file exists using scp

I am writing a bash script to copy a file from a remote server, to my local machine. I need to check to see if the file is available, so I can take an alternative action if it is not there.
I know how to test if a local file exists, however, using scp complicates things a bit. Common sense tells me that one way would be to try to scp the file anyhow, and check the return code from the scp command. Is this the correct way to go about it?
If yes, how do I test the return code from the scp invocation?
using ssh + some shell code embedded in the cmd line; use this method when you need to take a decision before the file transfer will fail;
ssh remote-host 'sh -c "if [ -f ~/myfile ] ; then gzip -c ~/myfile ; fi" ' | gzip -dc > /tmp/pkparse.py
if you want to transfer directories you may want to "tar"-it first
if you want to use scp you can check the return code like this:
if scp remote-host:~/myfile ./ >&/dev/null ; then echo "transfer OK" ; else echo "transfer failed" ; fi
it really depends on when its important for you to know if the file is there or not; before the transfer starts (use ssh+sh) or after its finished.
well, since you can use scp you can try using ssh to list and see if the file is their or not before proceeding.

How can I upload (FTP) files to server in a Bash script?

I'm trying to write a Bash script that uploads a file to a server. How can I achieve this? Is a Bash script the right thing to use for this?
Below are two answers. First is a suggestion to use a more secure/flexible solution like ssh/scp/sftp. Second is an explanation of how to run ftp in batch mode.
A secure solution:
You really should use SSH/SCP/SFTP for this rather than FTP. SSH/SCP have the benefits of being more secure and working with public/private keys which allows it to run without a username or password.
You can send a single file:
scp <file to upload> <username>#<hostname>:<destination path>
Or a whole directory:
scp -r <directory to upload> <username>#<hostname>:<destination path>
For more details on setting up keys and moving files to the server with RSYNC, which is useful if you have a lot of files to move, or if you sometimes get just one new file among a set of random files, take a look at:
http://troy.jdmz.net/rsync/index.html
You can also execute a single command after sshing into a server:
From man ssh
ssh [...snipped...] hostname [command] If command is specified, it is
executed on the remote host instead of a login shell.
So, an example command is:
ssh username#hostname.example bunzip file_just_sent.bz2
If you can use SFTP with keys to gain the benefit of a secured connection, there are two tricks I've used to execute commands.
First, you can pass commands using echo and pipe
echo "put files*.xml" | sftp -p -i ~/.ssh/key_name username#hostname.example
You can also use a batchfile with the -b parameter:
sftp -b batchfile.txt ~/.ssh/key_name username#hostname.example
An FTP solution, if you really need it:
If you understand that FTP is insecure and more limited and you really really want to script it...
There's a great article on this at http://www.stratigery.com/scripting.ftp.html
#!/bin/sh
HOST='ftp.example.com'
USER='yourid'
PASSWD='yourpw'
FILE='file.txt'
ftp -n $HOST <<END_SCRIPT
quote USER $USER
quote PASS $PASSWD
binary
put $FILE
quit
END_SCRIPT
exit 0
The -n to ftp ensures that the command won't try to get the password from the current terminal. The other fancy part is the use of a heredoc: the <<END_SCRIPT starts the heredoc and then that exact same END_SCRIPT on the beginning of the line by itself ends the heredoc. The binary command will set it to binary mode which helps if you are transferring something other than a text file.
You can use a heredoc to do this, e.g.
ftp -n $Server <<End-Of-Session
# -n option disables auto-logon
user anonymous "$Password"
binary
cd $Directory
put "$Filename.lsm"
put "$Filename.tar.gz"
bye
End-Of-Session
so the ftp process is fed on standard input with everything up to End-Of-Session. It is a useful tip for spawning any process, not just ftp! Note that this saves spawning a separate process (echo, cat, etc.). It is not a major resource saving, but it is worth bearing in mind.
The ftp command isn't designed for scripts, so controlling it is awkward, and getting its exit status is even more awkward.
Curl is made to be scriptable, and also has the merit that you can easily switch to other protocols later by just modifying the URL. If you put your FTP credentials in your .netrc, you can simply do:
# Download file
curl --netrc --remote-name ftp://ftp.example.com/file.bin
# Upload file
curl --netrc --upload-file file.bin ftp://ftp.example.com/
If you must, you can specify username and password directly on the command line using --user username:password instead of --netrc.
Install ncftpput and ncftpget. They're usually part of the same package.
Use this to upload a file to a remote location:
#!/bin/bash
#$1 is the file name
#usage:this_script <filename>
HOST='your host'
USER="your user"
PASSWD="pass"
FILE="abc.php"
REMOTEPATH='/html'
ftp -n $HOST <<END_SCRIPT
quote USER $USER
quote PASS $PASSWD
cd $REMOTEPATH
put $FILE
quit
END_SCRIPT
exit 0
The command in one line:
ftp -in -u ftp://username:password#servername/path/to/ localfile
#/bin/bash
# $1 is the file name
# usage: this_script <filename>
IP_address="xx.xxx.xx.xx"
username="username"
domain=my.ftp.domain
password=password
echo "
verbose
open $IP_address
USER $username $password
put $1
bye
" | ftp -n > ftp_$$.log
Working example to put your file on root...see, it's very simple:
#!/bin/sh
HOST='ftp.users.qwest.net'
USER='yourid'
PASSWD='yourpw'
FILE='file.txt'
ftp -n $HOST <<END_SCRIPT
quote USER $USER
quote PASS $PASSWD
put $FILE
quit
END_SCRIPT
exit 0
There isn't any need to complicate stuff. This should work:
#/bin/bash
echo "
verbose
open ftp.mydomain.net
user myusername mypassword
ascii
put textfile1
put textfile2
bin
put binaryfile1
put binaryfile2
bye
" | ftp -n > ftp_$$.log
Or you can use mput if you have many files...
If you want to use it inside a 'for' to copy the last generated files for an everyday backup...
j=0
var="`find /backup/path/ -name 'something*' -type f -mtime -1`"
# We have some files in $var with last day change date
for i in $var
do
j=$(( $j + 1 ))
dirname="`dirname $i`"
filename="`basename $i`"
/usr/bin/ftp -in >> /tmp/ftp.good 2>> /tmp/ftp.bad << EOF
open 123.456.789.012
user user_name passwd
bin
lcd $dirname
put $filename
quit
EOF # End of ftp
done # End of 'for' iteration
echo -e "open <ftp.hostname>\nuser <username> <password>\nbinary\nmkdir New_Folder\nquit" | ftp -nv

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