[#install-compose]
= Docker Compose install

Docker compose is a popular way to define multi-container applications using a 
infrastructure as code approach. 

If you personally prefer to use `docker compose`, then here is a sample to get
you started;

[source,yaml]
.`docker-compose.yml`
----
services:
  olivetin:
    container_name: olivetin
    image: jamesread/olivetin
    volumes:
      - OliveTin-config:/config # replace host path or volume as needed
    ports: 
      - "1337:1337"
    restart: unless-stopped


volumes:
  OliveTin-config:
    external: false
----

include::partial$install/post_container.adoc[]

[#compose-docker-socket]
== Controlling other docker containers from a Docker Compose install of OliveTin

If you want OliveTin running in a container to control other Docker containers, pass the Docker socket into the service and give the container process membership in the same numeric `docker` group that owns the socket on the host.

On many Linux installs, Docker Engine creates a `docker` group automatically; see https://docs.docker.com/engine/install/linux-postinstall/#manage-docker-as-a-non-root-user[Manage Docker as a non-root user] in the Docker documentation.

=== Find the `docker` group GID on the host

On the Docker host, read the `docker` group numeric ID (third field of the output):

[source,bash]
----
getent group docker
----

If that command prints nothing, create the group or finish Docker post-install steps first, then retry.

=== Add the socket mount and `group_add` in Compose

In `docker-compose.yml`, bind-mount the socket and add `group_add` with that GID (as a string is fine). Replace the example GID with the value from your host:

[source,yaml]
.`docker-compose.yml` including Docker socket access without running as root
----
services:
  olivetin:
    container_name: olivetin
    image: jamesread/olivetin
    volumes:
      - /docker/OliveTin:/config # replace host path or volume as needed
      - /var/run/docker.sock:/var/run/docker.sock
    group_add:
      - "992" # <1>
----
<1> Replace `992` with the GID from `getent group docker` on the machine where Compose runs. The number is not portable between hosts.

This keeps the default container user while allowing access to `/var/run/docker.sock`, which is usually tighter than running the whole service as `root`.

See xref:action_examples/containers.adoc[containers] for `docker run`, `--privileged`, and other options if you cannot use a `docker` group on the host.

== Running the OliveTin container as a different user in Compose

If you need the service to run as a specific Unix user in Compose for reasons other than Docker socket access, set `user` explicitly, for example:

[source,yaml]
----
services:
  olivetin:
    container_name: olivetin
    image: jamesread/olivetin
    user: "1000:1000"
    ...
----

For Docker socket access from Compose, prefer <<compose-docker-socket,`group_add` with the host `docker` group GID>> instead of `user: root`.


NOTE: xref:troubleshooting/puid-pgid.adoc[PUID and PGID are not used] by the official OliveTin container image.

[#docker-compose-traefik]
== Using Traefik with Docker Compose 

Traefik is a popular reverse proxy that seems to be used a lot in people's
Docker compose setups. See the xref:reverse-proxies/traefik.adoc[Traefik + Docker Compose] page for more details.


