Why is exit my status valid in command line but not within bash script? (Bash) - bash

Question

There are a few layers here, so bear with me.
My docker-container ssh -c"echo 'YAY!'; exit 25;" command executes echo 'YAY!'; exit 25; in my docker container. It returns:
YAY
error: message=YAY!
, code=25
I need to know if the command within the container was successful, so I append the following to the command:
docker-container ssh -c"echo 'YAY!'; exit 25;" >&1 2>/tmp/stderr; cat /tmp/stderr | grep 'code=' | cut -d'=' -f2 | { read exitStatus; echo $exitStatus; }
This sends the stderr to /tmp/stderr and, with the echo $exitStatus returns:
YAY!
25
So, this is exactly what I want. I want the $exitStatus saved to a variable. My problem is, I am placing this into a bash script (GIT pre-commit) and when this exact code is executed, the exit status is null.
Here is my bash script:
# .git/hooks/pre-commit
if [ -z ${DOCKER_MOUNT+x} ];
then
docker-container ssh -c"echo 'YAY!'; exit 25;" >&1 2>/tmp/stderr; cat /tmp/stderr | grep 'code=' | cut -d'=' -f2 | { read exitStatus; echo $exitStatus; }
exit $exitStatus;
else
echo "Container detected!"
fi;

Answer 1

That's because you're setting the variable in a pipeline. Each command in the pipeline is run in a subshell, and when the subshell exits the variable are no longer available.
bash allows you to run the pipeline's last command in the current shell, but you also have to turn off job control
An example
# default bash
$ echo foo | { read x; echo x=$x; } ; echo x=$x
x=foo
x=
# with "lastpipe" configuration
$ set +m; shopt -s lastpipe
$ echo foo | { read x; echo x=$x; } ; echo x=$x
x=foo
x=foo
Add set +m; shopt -s lastpipe to your script and you should be good.
And as Charles comments, there are more efficient ways to do it. Like this:
source <(docker-container ssh -c "echo 'YAY!'; exit 25;" 2>&1 1>/dev/null | awk -F= '/code=/ {print "exitStatus=" $2}')
echo $exitStatus