Passing variables to SSH [duplicate] - shell

Question

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Passing external shell script variable via ssh
(2 answers)
Variable issues in SSH
(1 answer)
Closed 1 year ago.
The following code loops through states in a array and passes a state to a server via ssh -
STATES="NY CO"
arr_states=(${STATES//' /'/ })
for i in "${arr_states[#]}"; do
state=$i
ssh -o SendEnv=state jenkins#server sh -s << 'EOF'
sudo su
cd /home/jenkins/report
psql -d db -c "$(sed 's/state_name/'"$state"'/' county.sql)" -U user
echo $state
EOF
done
The output of echo $state in the above is an empty string even if I pass it NY.
When I change the 'EOF' to EOF, the output of echo $state is the string I passed (NY). But then it says, the file county.sql does not exist.
How do I get it to recognize both the variable I pass and the file on the remote I am trying to run.

Answer 1

As an approach that doesn't require you to do any manual escaping of your code (which frequently becomes a maintenance nightmare, since it means that code needs to be changed whenever you modify where it's expected to run) -- consider defining a function, and using declare -f to ask the shell to generate code that will output that function for you.
The same can be done with variables, using declare -p. Thus, passing both a function with the remote code, and the variables that remote code needs to operate that way:
#!/usr/bin/env bash
# This is run on the remote server _as root_ (behind sudo su)
remotePostEscalationFunc() {
cd /home/jenkins/report || return
if psql -d db -U user -c "$(sed -e "s/state_name/${state}/" county.sql)"; then
echo "Success processing $state" >&2
else
rc=$?
echo "Failure processing $state" >&2
return "$rc"
fi
}
# This is run on the remote server as the jenkins user (before sudo).
remoteFunc() {
sudo su -c "$(declare -p state); $(declare -f remotePostEscalationFunc); remotePostEscalationFunc"
}
# Everything below here is run locally.
arr_states=( NY CO )
for state in "${arr_states[#]}"; do
ssh jenkins#server 'bash -s' <<EOF
$(declare -f remoteFunc remotePostEscalationFunc); $(declare -p state); remoteFunc
EOF
done

Answer 2

You were almost right with the change from 'EOF' to EOF. You are just missing a backslash (\) before $(sed. So the following should work:
arr_states=(${STATES//' /'/ })
for i in "${arr_states[#]}"; do
state=$i
ssh -o SendEnv=state jenkins#server sh -s << EOF
sudo su
cd /home/jenkins/report
psql -d db -c "\$(sed 's/state_name/'"$state"'/' county.sql)" -U user
echo $state
EOF
done