Setup a basic configuration for postfix and dovecot

Dockerfile

@@ -1,11 +1,14 @@
 FROM debian:jessie
 
-RUN apt-get update \
+RUN export DEBIAN_FRONTEND=noninteractive \
+ && apt-get update \
  && apt-get install -y --no-install-recommends \
-      postfix dovecot-imapd dovecot-sqlite \ # basics
-      dovecot-sieve dovecot-managesieved \ # filters
-      dovecot-antispam spamassassin clamav \ # additional utilities
-      supervisord \ # glue
+      postfix dovecot-imapd dovecot-sqlite \
+      dovecot-sieve dovecot-managesieved \
+      dovecot-antispam spamassassin clamav \
+      supervisor \
  && apt-get clean
 
 ADD config /etc/
+
+CMD ["/usr/bin/supervisord"]

config/supervisor/supervisord.conf

@@ -0,0 +1,8 @@
+[supervisord]
+nodaemon = true
+
+[program:postfix]
+command = /usr/lib/postfix/master -d
+
+[program:dovecot]
+command = /usr/sbin/dovecot -c /etc/dovecot/dovecot.conf -F