#!/usr/bin/env bash
# Start a real RabbitMQ broker with no Docker and no root.
#
# RabbitMQ is an Erlang application, so an Erlang runtime and epmd on the path are the whole
# dependency. Point ERL_ROOT at an Erlang installation and RABBITMQ_HOME at an unpacked
# rabbitmq-server-generic-unix tarball. Ubuntu 22.04 ships Erlang 24, whose newest compatible
# broker is 3.10.25; 3.11 and later need Erlang 25.
#
# The one non-obvious step is starting epmd yourself: rabbitmq-server's own attempt to start it
# fails in a container without a resolvable hostname, and the failure surfaces as a forty-line
# Erlang crash dump ending in {'EXIT',nodistribution}.
set -eu
: "${ERL_ROOT:?set ERL_ROOT to an Erlang installation directory}"
: "${RABBITMQ_HOME:?set RABBITMQ_HOME to an unpacked rabbitmq-server-generic-unix directory}"

export PATH="$ERL_ROOT/bin:$ERL_ROOT/erts-"*/bin":$PATH"
export RABBITMQ_MNESIA_BASE="${RABBITMQ_MNESIA_BASE:-/tmp/rmq/data}"
export RABBITMQ_LOG_BASE="${RABBITMQ_LOG_BASE:-/tmp/rmq/log}"
export RABBITMQ_NODENAME="${RABBITMQ_NODENAME:-rabbit@localhost}"
export HOME="${HOME:-/tmp/rmq}"
mkdir -p "$RABBITMQ_MNESIA_BASE" "$RABBITMQ_LOG_BASE"

epmd -daemon 2>/dev/null || true
sleep 1
setsid nohup "$RABBITMQ_HOME/sbin/rabbitmq-server" > /tmp/rmq/boot.log 2>&1 < /dev/null &
for _ in $(seq 1 60); do
  if (echo > /dev/tcp/127.0.0.1/5672) 2>/dev/null; then echo "broker ready on 5672"; exit 0; fi
  sleep 1
done
echo "broker did not start; see /tmp/rmq/boot.log" >&2
exit 1