Can GroupServices header1.. or param1... be given variables

For example:
header1: value1
but what I would like to do is:
header1: @{REMOTE_HOST}

When I try to do this it complains about the @ sign
Can environment variables or header variables from the request be passed as header1 …etc?

I also tried ${REMOTE_HOST} but that doesn’t complain but passes “${REMOTE_HOST}” and not the value of REMOTE_HOST

Sorry, but in what context? Could you please share your ROR version, ES version, the complete settings file and state your requirement? Please edit your original post to include these things, rather than replying.