Add a postgres database container.

- Set environemnt variables for Postgresql database in the compose file
- Set environment variables for uwsgi in the compose file
- Check if the postgresql container is up and accepting connections before
  running any actual services.

core/Dockerfile

@@ -4,7 +4,9 @@ MAINTAINER Abhilash Raj
 
 # Install the latest master branch of the mailman directly
 # from the Gitlab.
-RUN pip install git+https://gitlab.com/mailman/mailman.git
+RUN apt-get update && apt-get install -y postgresql-client \
+    && pip install git+https://gitlab.com/mailman/mailman.git \
+	               psycopg2
 
 ADD assets/run.sh /opt/run.sh
 
@@ -17,4 +19,4 @@ WORKDIR /opt/mailman
 
 EXPOSE 8001
 
-CMD /opt/run.sh
+CMD ["/opt/run.sh"]

core/assets/run.sh

@@ -1,4 +1,5 @@
 #! /bin/bash
+set -e
 
 # Check if the configuration file is present.
 if [[ ! -e /opt/mailman/mailman.cfg ]]; then
@@ -6,6 +7,30 @@ if [[ ! -e /opt/mailman/mailman.cfg ]]; then
 	exit 1
 fi
 
+if [[ ! -e /opt/mailman/mailman-hyperkitty.cfg ]]; then
+	echo "/opt/mailman/mailman-hyperkitty.cfg configuration file not found..."
+	echo "Hyperkitty will not be enabled or will not work properly..."
+fi
+
+# Check if the master lock exists for the mailman.
+# It means that that either some other mailman process is running or
+# the last time mailman did not exit clean.
+if [[ -e /opt/mailman/core/var/locks/master.lck ]]; then
+	echo "The mailman's master lock file still exists at /opt/mailman/core/var/locks/master.lck"
+	echo "Please remove the lock file before trying to run this container again."
+	exit 1
+fi
+
+# Check if the database is available yet. Do not start the container before the
+# postgresql boots up.
+until psql $DATABASE_URL -c '\l'; do
+  >&2 echo "Postgres is unavailable - sleeping"
+  sleep 1
+done
+
+>&2 echo "Postgres is up - continuing"
+
+
 # Run mailman using the pidproxy command which spawns off mailman
 # and forwards any signal you send it to the master runner in mailman.
 /opt/pidproxy.py /opt/mailman/var/master.pid mailman -C /opt/mailman/mailman.cfg start --force