setup `monit` on home assistant

.gitignore

setupMonit.conf

setupMonit

# See https://community.home-assistant.io/t/monit-for-monitoring-ha-including-restart-and-more/353252

# SCRIPT PATHS
MYDIR=$(realpath $(dirname 0))
CONFFILE="${MYDIR}/setupMonit.conf"

# CONFIGURATIONS DEFINITIONS, OVERRIDE BY ADDING LOCAL setupMonit.conf
# Host and port for HA,
#  `curl http://homeassistant:8123` gives home page
#  `curl http://homeassistant:8123/api/` gives '401: Unauthorized' (not ... Forbidden):
#
# or set to other working host, sometimes pubic host works `curl https://publichaurl`
#  update protocol http to https if needed
#  (Testing https, also tests the nginx proxy)

HA_HTTP_HOST=homeassistant
HA_HTTP_PORT=8123
PROTOCOL=http
# Otherwise, define HA_HTTP_HOST to empty value

EMAILLOGIN="YOUREMAILLOGIN"
EMAILPASSWORD="YOUREMAILPASSWORD"
MAILSERVER=YOURMAILSERVER


# Read user settings overriding examples above
[ -r "$CONFFILE" ] && . $CONFFILE

# Script (adjust some variables to correspond to your setup):

mkdir -p /etc/monit.d

# change line with uncomment include of monit.d
sed -i 's@#\(\s*include\s*/etc/monit.d\)@\1@' /etc/monitrc
sed -i 's@set log syslog@set log /var/log/monit.log@' /etc/monitrc

if [ "$HA_HTTP_HOST" != "" ] ; then
  cat > /etc/monit.d/ha <<EOHA
  check host ha with address $HA_HTTP_HOST
    # with pidfile PATHTOPIDFILE
    if failed
       port $HA_HTTP_PORT protocol $PROTOCOL
       # Expect unauthorized, shows that the server is up
       # Could check status if API key provided.
       #and request /api/ with content = "401: Unauthorized" with timeout 20 seconds
       and request / with timeout 20 seconds
       then
         exec "/usr/bin/ha core restart"
    group ha
EOHA
fi


# RESTART HA when CPU LOAD is high for 10 minutes
cat > /etc/monit.d/checkload <<EOCPUHIGH
check system homeassistant.local
  if loadavg (1min) per core > 1.5 for 10 cycles then alert
  if loadavg (1min) per core > 1.5 for 15 cycles then exec "/usr/bin/ha core restart"
EOCPUHIGH

# Its possible to set up mail alerts.
# Example for server using TLS on port 587:



cat > /etc/monit.d/mailserver <<EOMS
set mailserver
      $MAILSERVER port 587 username "$EMAILLOGIN" password "$EMAILPASSWD" using tlsv1
EOMS

monit
monit reload
sleep 1
monit summary