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Seeking help with a curl command in a bash script - SOLVED (lemmy.thewooskeys.com)

submitted 1 week ago* (last edited 1 week ago) by [email protected] to c/[email protected]

23 comments fedilink hide all child comments

I've got this command in a bash script:

TEST=$(curl -o /dev/null -s -k -w "%{http_code}" -u "${USERNAME}:${PASSWORD}" "${URL}/dashboard/")
echo "${TEST}" #debug

When the script runs, the output is "000".

When I run the same curl command from the shell, the output is "200" (which is correct, since the URL is valid).

I verified that the USERNAME, PASSWORD, and URL vars are being passed to the subshell.

I'd appreciate it if you could point out what I'm doing wrong here. :)

UPDATE: This has been solved.

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[–] [email protected] 2 points 1 week ago (3 children)

I stumbled on a possible cause, but more background is necessary to explain.

The script actually creates an ssh tunnel (to the Traefik host) and then does the curl. So the code is like:

SSH_CMD="ssh -N -L ${LOCAL_PORT}:127.0.0.1:${REMOTE_PORT} ${REMOTE_USER}@${REMOTE_HOST}"
$SSH_CMD &
SSH_PID=$!
SSH_RESULT=$?

TEST=$(curl -o /dev/null -s -k -w "%{http_code}" -u "${USERNAME}:${PASSWORD}" "${URL}/dashboard/")
echo "${TEST}" #debug

What I learned is that when i run the script, the tunnel is successfully created but the curl fails; but then if I run the script again a second tunnel is created and the curl works fine.

[–] rwdf 1 points 1 week ago* (last edited 1 week ago) (1 children)

Ah, I see. ~~I guess they get different contexts or something?~~ (Edit: I re-read your post and this does not make any sense :)) What if you chain the ssh command and the curl using &&?

[–] [email protected] 1 points 1 week ago

I'm not sure how to chain these 2 commands with &&, because the SSH command is being put in the background with &.

This doesn't work:

SSH_CMD="ssh -N -L ${LOCAL_PORT}:127.0.0.1:${REMOTE_PORT} ${REMOTE_USER}@${REMOTE_HOST}"
$SSH_CMD & && TEST=$(curl -o /dev/null -s -k -w "%{http_code}" -u "${USERNAME}:${PASSWORD}" "${URL}/dashboard/")
SSH_PID=$!
SSH_RESULT=$?
echo $TEST

Perhaps I don't need it in the background - the goal was to establish the tunnel and then continue with the script without it hanging until the ssh command is canceled.

[–] [email protected] 1 points 1 week ago (1 children)

Try to add -f to ssh command

[–] [email protected] 2 points 1 week ago (1 children)

That seems to have done it!

Running the ssh -f... instead of ssh.... & seems to work first time and every time.

It makes it so SSH_PID=$! doesn't work, but I used pgrep -f <ssh command> instead.

Thanks!

[–] [email protected] 1 points 1 week ago

You are very welcome! That was the hypothesis, that ssh doesn’t go into background as you want it to, since it works for the second run, but tunnel is there after the first.

[–] rwdf 1 points 1 week ago

Are you trying to reach a URL on the same host you're ssh-ing to? That would create some interesting effects.

Especially since it works the second time it could mean that the second time you're actually on the host and ssh-ing to the host itself and then curling localhost.