Add Docker volume persistence (#159)

* Add persistence to the default Docker container

This sets a default volume of `/data` for the Docker container.
This allows for persistence when using the default SQLite database, and the option of mounting the volume to the host for backing up.

* Add -v flag description

Co-authored-by: Jesús Espino <jespinog@gmail.com>

docker/Dockerfile

@@ -21,6 +21,8 @@ ARG PGID=2000
 
 EXPOSE 8000/tcp
 
+VOLUME /data
+
 RUN addgroup -g ${PGID} focalboard && \
     adduser -H -D -u ${PUID} -G focalboard focalboard
 
@@ -29,7 +31,7 @@ WORKDIR /opt/focalboard
 COPY --from=gobuild /go/focalboard/bin/linux/focalboard-server bin/
 COPY --from=nodebuild /focalboard/webapp/pack pack/
 COPY --from=nodebuild /focalboard/LICENSE.txt LICENSE.txt
-COPY --from=nodebuild /focalboard/server-config.json config.json
+COPY --from=nodebuild /focalboard/docker/server_config.json config.json
 
 RUN chown -R ${PUID}:${PGID} /opt/focalboard
 

docker/README.md

@@ -6,9 +6,11 @@ The Dockerfile gives a quick and easy way to pull the latest Focalboard server a
 
 ```
 docker build -t focalboard .
-docker run -it -p 80:8000 focalboard
+docker run -it -v "/home/user/focalboard-data:/data" -p 80:8000 focalboard
 ```
 
+> The `-v` flag can be used to store Focalboard's database and uploaded files in a directory on the Docker host
+
 Open a browser to http://localhost to start
 
 ## Docker-Compose

docker/server_config.json

@@ -0,0 +1,16 @@
+{
+  "serverRoot": "http://localhost:8000",
+  "port": 8000,
+  "dbtype": "sqlite3",
+  "dbconfig": "/data/focalboard.db",
+  "postgres_dbconfig": "dbname=focalboard sslmode=disable",
+  "useSSL": false,
+  "webpath": "./pack",
+  "filespath": "/data/files",
+  "telemetry": true,
+  "session_expire_time": 2592000,
+  "session_refresh_time": 18000,
+  "localOnly": false,
+  "enableLocalMode": true,
+  "localModeSocketLocation": "/var/tmp/focalboard_local.socket"
+}