Docker: Move configuration back to a dedicated folder to allow proper…

… host mounting (fixes #34)

Dockerfile

@@ -1,8 +1,8 @@
 FROM alpine:latest
 WORKDIR /opt/kelvin
-VOLUME /opt/kelvin
+VOLUME /etc/opt/kelvin
 
 RUN apk --no-cache add ca-certificates tzdata && update-ca-certificates
 COPY dist/kelvin-linux-amd64-v* /opt/kelvin/
 
-ENTRYPOINT /opt/kelvin/kelvin -enableWebInterface 2>&1 | tee /var/log/kelvin.log
+ENTRYPOINT /opt/kelvin/kelvin -enableWebInterface -configuration=/etc/opt/kelvin/config.json 2>&1 | tee /var/log/kelvin.log

README.md

@@ -82,7 +82,8 @@ As an alternative to manual installation you can also pull the official [docker
 - Start a container via ```docker run -d -e TZ=Europe/Berlin -p 8080:8080 stefanwichmann/kelvin``` (replace Europe/Berlin with your local [timezone](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones))
 - ```docker ps``` should now report your running container
 - Run ```docker logs {CONTAINER_ID}``` to see the kelvin output (You can get the valid ID from ```docker ps```)
-- To adjust the configuration you should use the web interface running at ```http://{DOCKER_HOST_IP}:8080/```. As an alternative log into your container via ```docker exec -it {CONTAINER_ID} /bin/sh``` and edit the file ```/opt/kelvin/config.json```. After changing the configuration you have to restart Kelvin through the web interface or by ```docker restart {CONTAINER_ID}```.
+- To adjust the configuration you should use the web interface running at ```http://{DOCKER_HOST_IP}:8080/```.
+- If you want to keep your configuration over the lifetime of your container, you can map the folder ```/etc/opt/kelvin/``` to your host filesystem. If you alter the configuration you have to restart Kelvin through the web interface or by running ```docker restart {CONTAINER_ID}```.
 
 # Configuration
 Kelvin will create it's configuration file `config.json` in the current directory and store all necessary information to operate in it. By default it is fully usable and looks like this: