Add docker swarm mode support (#176)

* add docker swarm mode support

Signed-off-by: Pierre DEMAGNY <pdemagny@printoclock.com>

* use official prod-web image, respect project's standard directory layout & update readme accordingly.

Signed-off-by: Pierre DEMAGNY <pdemagny@printoclock.com>

README.md

@@ -139,6 +139,27 @@ docker-compose up -d
 ```
 See the [offical Upgrade Guide](http://docs.mattermost.com/administration/upgrade.html) for more details.
 
+## Installation using Docker Swarm Mode
+
+The following instructions deploy Mattermost in a production configuration using docker swarm mode on one node.
+Running containerized applications on multi-node swarms involves specific data portability and replication handling that are not covered here.
+
+### Requirements
+
+* [docker] (1.12.0+)
+
+### Swarm Mode Installation
+
+First, create mattermost directory structure on the docker hosts:
+```
+mkdir -p /var/lib/mattermost/{cert,config,data,logs}
+```
+
+Then, fire up the stack in your swarm:
+```
+docker stack deploy -c contrib/swarm/docker-stack.yml mattermost
+```
+
 ## Known Issues
 
 * Do not modify the Listen Address in Service Settings.

contrib/swarm/docker-stack.yml

@@ -0,0 +1,78 @@
+# This file allow you to run mattermost within your docker swarm mode cluster
+# for more informations check: https://docs.docker.com/engine/swarm/
+#
+# use latest compose v3.3 file format for optimal compatibility with latest docker release and swarm features.
+# see https://docs.docker.com/compose/compose-file/compose-versioning/#version-3
+# and https://docs.docker.com/compose/compose-file/compose-versioning/#version-33
+# and https://docs.docker.com/compose/compose-file/compose-versioning/#upgrading
+
+version: '3.3'
+
+services:
+    db:
+        # use official mattermost prod-db image
+        image: mattermost/mattermost-prod-db:latest
+        ports:
+            - "5432"
+        networks:
+            - mm-network
+        volumes:
+            # use a named-volume for data persistency
+            - mm-dbdata:/var/lib/postgresql/data
+            - /etc/localtime:/etc/localtime:ro
+        environment:
+            POSTGRES_USER: mmuser
+            POSTGRES_PASSWORD: mmuser_password
+            POSTGRES_DB: mattermost
+            # uncomment the following to enable backup
+            # AWS_ACCESS_KEY_ID=XXXX
+            # AWS_SECRET_ACCESS_KEY=XXXX
+            # WALE_S3_PREFIX=s3://BUCKET_NAME/PATH
+            # AWS_REGION=us-east-1
+        deploy:
+            restart_policy:
+                condition: on-failure
+    app:
+        # use official mattermost prod-app image
+        image: mattermost/mattermost-prod-app:latest
+        ports:
+            - "8065"
+        networks:
+            - mm-network
+        volumes:
+            - /var/lib/mattermost/config:/mattermost/config:rw
+            - /var/lib/mattermost/data:/mattermost/data:rw
+            - /var/lib/mattermost/logs:/mattermost/logs:rw
+            - /etc/localtime:/etc/localtime:ro
+        environment:
+            DB_HOST: db
+            DB_PORT_NUMBER: 5432
+            MM_USERNAME: mmuser
+            MM_PASSWORD: mmuser_password
+            MM_DBNAME: mattermost
+            # in case your config is not in default location
+            # MM_CONFIG=/mattermost/config/config.json
+        deploy:
+            restart_policy:
+                condition: on-failure
+    web:
+        # use official mattermost prod-web image
+        image: mattermost/mattermost-prod-web:latest
+        ports:
+            - "80:80"
+            - "443:443"
+        networks:
+            - mm-network
+        volumes:
+            # This directory must have cert files
+            - /var/lib/mattermost/cert:/cert:ro
+            - /etc/localtime:/etc/localtime:ro
+        deploy:
+            restart_policy:
+                condition: on-failure
+
+networks:
+    mm-network:
+
+volumes:
+    mm-dbdata: