autoconfigure email

.woodpecker.yml

@@ -8,14 +8,10 @@ pipeline:
     - latest
     build_args:
     - EMAIL=${MONIT_EMAIL}
-    - EMAIL_FROM=${MONIT_EMAIL_FROM}
-    - ALPINE_VERSION=${ALPINE_VERSION}
     - BASE_IMAGE=alpine
     username: sutty
     secrets:
     - docker_password
-    - monit_email
-    - monit_email_from
     cache_from: registry.nulo.in/sutty/monit:${ALPINE_VERSION}
     docker:
       purge: false

Dockerfile

@@ -6,13 +6,10 @@ FROM ${BASE_IMAGE}:${ALPINE_VERSION} as build
 ARG EMAIL
 ARG EMAIL_FROM
 
-RUN apk add --no-cache tzdata monit
+RUN apk add --no-cache tzdata
 
 COPY ./monitrc /etc/monitrc
 RUN chmod 600 /etc/monitrc
-RUN sed -re "s/@@EMAIL@@/${EMAIL}/" -i /etc/monitrc
-RUN sed -re "s/@@EMAIL_FROM@@/${EMAIL_FROM}/" -i /etc/monitrc
-RUN monit -t
 
 FROM ${BASE_IMAGE}:${ALPINE_VERSION}
 ARG ALPINE_VERSION
@@ -37,6 +34,8 @@ RUN install -dm 2750 -o root -g root /var/lib/monit
 COPY --from=build /etc/monitrc /etc/monitrc
 COPY ./nsupdate.sh /usr/local/bin/nsupdate
 COPY ./whatsmyip6.sh /usr/local/bin/whatsmyip6
+COPY ./email.sh /usr/local/bin/email
+COPY ./email.conf /etc/email.conf
 
 # Allow access to the web GUI
 EXPOSE 2812

email.conf

@@ -0,0 +1,9 @@
+set mailserver postfix port 25 using hostname @@HOSTNAME@@
+
+set alert @@EMAIL@@
+
+set mail-format {
+  from: Monit <@@EMAIL_FROM@@>
+  subject: $SERVICE@$HOST
+  message: $ACTION $SERVICE -- $DATE -- $HOST: $DESCRIPTION.
+}

email.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+set -e
+
+test ! -f /etc/monit.d/email.conf || exit 0
+
+test -n "${EMAIL}"
+test -n "${EMAIL_FROM}"
+
+sed -re "s/@@EMAIL@@/${EMAIL}/" \
+     -e "s/@@EMAIL_FROM@@/${EMAIL_FROM}/" \
+     -e "s/@@HOSTNAME@@/${EMAIL_FROM#*@}/" \
+     /etc/email.conf > /etc/monit.d/email.conf
+
+monit -t
+monit reload

monitrc

@@ -5,23 +5,21 @@ set pidfile /run/monit.pid
 set idfile /var/lib/monit/id
 set statefile /var/lib/monit/state
 set eventqueue basedir /var/lib/monit/events slots 100
-set mailserver postfix
 set limits { programoutput: 1 MB }
-set alert @@EMAIL@@
 
 set httpd port 2812
   allow localhost
   allow 172.0.0.0/8
+  allow "fd00:acab::/32"
 
 check program nsupdate
   with path "/usr/local/bin/nsupdate"
   every 1 cycle
   if status = 0 then unmonitor
 
-set mail-format {
+check program email
-  from: Monit <@@EMAIL_FROM@@>
+  with path "/usr/local/bin/email"
-  subject: $SERVICE@$HOST
+  every 1 cycle
-  message: $ACTION $SERVICE -- $DATE -- $HOST: $DESCRIPTION.
+  if status = 0 then unmonitor
-}
 
 include /etc/monit.d/*.conf