Merge branch 'dev' into 'master'

## Deployment

At first time, you must deploy `gitlab-runner-registrar` to configure and register a new runner instance. Then, deploy `gitlab-runner` (launching default deployment jobs) to receive jobs to run.

First time, you must deploy `gitlab-runner-registrar` service to configure and register a new runner instance. This action creates a configuration file into a shared volume, ready for `gitlab-runner` to use.

Then, deploy `gitlab-runner` (launching default-named deployment jobs) to start receiving jobs to run.

## Delete old runners

Service will try to unregister old version of same runner being registered, before creating the new one.

When runners name change, you must delete old registrations manually. Go to a running gitlab-runner container shell and execute one of the following commands:

When runners name change, you must delete old registrations manually. Go to a running `gitlab-runner` container shell and execute one of the following commands:

```sh

# Remove one runner, by GitLab instance URL and runner token

# Remove all runners

gitlab-runner unregister --all-runners

```

## Environment isolation

This service is configured to work with `docker` executor. By default, your CI jobs will run in a Docker container launched at the host system of `gitlab-runner` service, sharing the same Docker daemon and resources (networks, volumes...) with host and other CI jobs running concurrently.

In some use cases this is a desired behaviour, because you need local resources from host or it's local network.

To achieve isolation from host's Docker environment (and other CI jobs running concurrently), you should use `dind` (docker-in-docker) as a service, applied to your CI job at `.gitlab-ci.yml`. This way, launched container cannot see any external resources.

IMAGE_TAG=alpine

CONFIG_FILE=/etc/gitlab-runner/config.toml

LISTEN_ADDRESS=:9252

CONCURRENT=3

REGISTRAR_LOG_LEVEL=info

LOG_LEVEL=warn

CI_SERVER_URL=https://gitlab.com/

REGISTRATION_TOKEN=changeme

REGISTER_NON_INTERACTIVE=true

REGISTER_LOCKED=false

REGISTER_RUN_UNTAGGED=true

REGISTER_MAXIMUM_TIMEOUT=7200

RUNNER_NAME=redmic-gitlab-runner

RUNNER_TAG_LIST=custom-runner

RUNNER_LIMIT=0

DOCKER_IMAGE=alpine:latest

DOCKER_PRIVILEGED=true

DOCKER_OOM_KILL_DISABLE=false

DOCKER_DISABLE_CACHE=false

DOCKER_NETWORK_MODE=gitlab-net

DOCKER_SHM_SIZE=1000000000

  gitlab-runner-registrar:

    image: ${IMAGE_NAME}:${IMAGE_TAG}

    entrypoint: /bin/sh

    command: >

      -c "

        gitlab-runner unregister --name \"${RUNNER_NAME}\";

        gitlab-runner register"

    command:

      - -c

      - |

        gitlab-runner unregister --name $$(echo "$${RUNNER_NAME}");

        gitlab-runner register;

        sed -i "$$(echo s/concurrent.*/concurrent = $${CONCURRENT}/)" $$(echo "$${CONFIG_FILE}")

    environment:

      CONFIG_FILE:

      CONCURRENT:

      LOG_LEVEL: ${REGISTRAR_LOG_LEVEL}

      CI_SERVER_URL:

      REGISTRATION_TOKEN:

      REGISTER_NON_INTERACTIVE:

      REGISTER_LOCKED:

      REGISTER_RUN_UNTAGGED:

      REGISTER_MAXIMUM_TIMEOUT:

      RUNNER_NAME:

      RUNNER_TAG_LIST:

      RUNNER_LIMIT:

      RUNNER_ENV:

      DOCKER_IMAGE:

      DOCKER_PRIVILEGED:

      DOCKER_OOM_KILL_DISABLE:

      DOCKER_DISABLE_CACHE:

      DOCKER_VOLUMES:

      DOCKER_NETWORK_MODE:

    image: ${IMAGE_NAME}:${IMAGE_TAG}

    environment:

      CONFIG_FILE:

      LISTEN_ADDRESS:

      LOG_LEVEL:

    networks:

      gitlab-net:

      metric-net:

    volumes:

      - /var/run/docker.sock:/var/run/docker.sock

      - config-vol:/etc/gitlab-runner

    name: ${GITLAB_NET_NAME}

    driver: ${GITLAB_NET_DRIVER}

    external: true

  metric-net:

    name: ${METRIC_NET_NAME:-metric-net}

    driver: ${METRIC_NET_DRIVER:-overlay}

    external: true