upstream-zulip/scripts/lib/warn-rabbitmq-nodename-change

#!/usr/bin/env bash

# For security reasons, we need to configure RabbitMQ to listen only
# on localhost, which we cannot do if the nodename contains the
# hostname (e.g. rabbit@zulip-host).  Containing the hostname also
# makes it brittle to hostname changes, which are (for example) common
# in containerized environments.

set -eu

# Try to find the current nodename
CURRENT=$(sh -c 'cd /usr/lib/rabbitmq/bin/ && . ./rabbitmq-env && echo $NODENAME')
if [ "$CURRENT" != "zulip@localhost" ]; then
    cat <<EOF

***** WARNING *****

We are renaming the rabbitmq server's nodename from '$CURRENT' to
'zulip@localhost', as rabbitmq is being reconfigured to listen only on
localhost.  This will also make the server more resilient to hostname
changes.  This will only affect you if you were using the rabbitmq
server for other, non-Zulip uses.

*******************

EOF

    service rabbitmq-server stop || true
fi