[SOLVED] How can I have a custom restart script for runit?

How can I have a custom restart script for runit?

I'm using runit to manage an HAProxy and want to do a safe restart to reload a configuration file (specifically: haproxy -f /etc/haproxy/haproxy.cfg -sf $OLD_PROCESS_ID). I figure that I could run sv restart haproxy and tried to add a custom script named /etc/service/haproxy/restart, but it never seems to execute. How do I have a special restart script? Is my approach even good here? How do I reload my config with minimal impact using runit?

Solution

HAProxy runit service script

/etc/service/haproxy/run

#!/bin/sh
#
# runit haproxy
#

# forward stderr to stdout for use with runit svlogd
exec 2>&1

PID_PATH=/var/run/haproxy/haproxy.pid
BIN_PATH=/opt/haproxy/sbin/haproxy
CFG_PATH=/opt/haproxy/etc/haproxy.cfg

exec /bin/bash <<EOF
$BIN_PATH -f $CFG_PATH -D -p $PID_PATH

trap "echo SIGHUP caught; $BIN_PATH -f $CFG_PATH -D -p $PID_PATH -sf \\\$(cat $PID_PATH)" SIGHUP
trap "echo SIGTERM caught; kill -TERM \\\$(cat $PID_PATH) && exit 0" SIGTERM SIGINT

while true; do # Iterate to keep job running.
  sleep 1 # Wake up to handle signals
done
EOF

Graceful reload that keeps things up and running.

sv reload haproxy

Full stop and start.

sv restart haproxy

This solution was inspired by https://gist.github.com/gfrey/8472007