How to pass a command which contains special characters through SSH? - regex

Question

I would like to run the following command from Jenkins:
ssh -i ~/.ssh/company.pem -o StrictHostKeyChecking=no user#$hostname "supervisorctl start company-$app ; awk -v app=$app '$0 ~ "program:company-"app {p=NR} p && NR==p+6 && /^autostart/ {$0="autostart=true" ; p=0} 1' /etc/supervisord.conf > $$.tmp && sudo mv $$.tmp /etc/supervisord.conf”
This is one of the last steps of a job which creates a CloudFormation stack.
Running the command from the target server's terminal works properly.
In this step, I'd like to ssh to each one of the servers (members of ASG's within the new stack) and search and replace a specific line as shown above in the /etc/supervisord.conf, basically setting one specific service to autostart.
When I run the command I get the following error:
Usage: awk [POSIX or GNU style options] -f progfile [--] file ...
Usage: awk [POSIX or GNU style options] [--] 'program' file ...
I've tried escaping the double quotes but got the same error, any idea what I'm doing wrong?

Answer 1

You are running in to this issue due to the way the shell handles nested quotes. This is a use case for a HERE DOCUMENT or heredoc - A HERE DOCUMENT allows you to write multi-line commands passed through bash without worrying about quotes. The structure is as follows:
$ ssh -t user#server.com <<'END'
command |\
command2 |\
END
<--- Oh yeah, the -t is important to the ssh command as it lets the shell know to behave as if being used interactively, and will avoid warnings and unexpected results.
In your specific case, you should try something like:
$ ssh -t -i ~/.ssh/company.pem -o StrictHostKeyChecking=no user#$hostname <<'END'
supervisorctl start company-$app |\
awk -v app=$app '$0 ~ \"program:company-\"app {p=NR} p && NR==p+6 \
&& /^autostart/ {$0="autostart=true" ; p=0} 1' \
/etc/supervisord.conf > $$.tmp && sudo mv $$.tmp /etc/supervisord.conf
END
Just a note, since I can't be sure about your desired output of the command you are running, be advised to keep track of your own " and ' marks, and to escape them accordingly in your awk command as you would at an interactive terminal. I notice the "'s around program:company and I am confused a bit by them If they are a part of the pattern in the string being searched they will need to be escaped accordingly. P.S.