ref(database): add data container to speed same-host maintenance

Author: Gabriel Monroy

deisctl/units/deis-database.service

@@ -4,10 +4,12 @@ Description=deis-database
 [Service]
 EnvironmentFile=/etc/environment
 TimeoutStartSec=20m
+ExecStartPre=/bin/sh -c "docker inspect deis-database-data >/dev/null 2>&1 || docker run --name deis-database-data -v /var/lib/postgresql ubuntu:14.04 /bin/true"
 ExecStartPre=/bin/sh -c "IMAGE=`/run/deis/bin/get_image /deis/database` && docker history $IMAGE >/dev/null || docker pull $IMAGE"
-ExecStart=/bin/sh -c "IMAGE=`/run/deis/bin/get_image /deis/database` && docker start -a deis-database >/dev/null || docker run --name deis-database -p 5432:5432 -e EXTERNAL_PORT=5432 -e HOST=$COREOS_PRIVATE_IPV4 $IMAGE"
+ExecStartPre=/bin/sh -c "docker inspect deis-database >/dev/null 2>&1 && docker rm -f deis-database >/dev/null 2>&1 || true"
+ExecStart=/bin/sh -c "IMAGE=`/run/deis/bin/get_image /deis/database` && docker run --name deis-database --volumes-from=deis-database-data -p 5432:5432 -e EXTERNAL_PORT=5432 -e HOST=$COREOS_PRIVATE_IPV4 $IMAGE"
 ExecStopPost=-/bin/bash -c "nsenter --pid --uts --mount --ipc --net --target $(docker inspect --format='{{ .State.Pid }}' deis-database) sudo service postgresql stop"
-ExecStopPost=-/usr/bin/docker stop deis-database
+ExecStopPost=-/usr/bin/docker rm -f deis-database
 Restart=on-failure
 RestartSec=5