Concourse CI inside Docker compose v2

docker-compose.yml

version: '2'
services:
  concourse-db:
    image: postgres:9.5
    volumes: ['database:/database']
    environment:
      POSTGRES_DB: concourse
      POSTGRES_USER: concourse
      POSTGRES_PASSWORD: changeme
      PGDATA: /database
    restart: on-failure:10

  concourse-web:
    image: concourse/concourse
    command: web
    ports: ['8080:8080']
    volumes: ['web-keys:/concourse-keys']
    depends_on: [keys, concourse-db]
    extra_hosts: ['dockerhost:$DOCKERHOST']
    environment:
      CONCOURSE_BASIC_AUTH_USERNAME: colthreepv
      CONCOURSE_BASIC_AUTH_PASSWORD: allthewin
      CONCOURSE_EXTERNAL_URL: http://dockerhost:8080
      CONCOURSE_POSTGRES_DATA_SOURCE: |-
        postgres://concourse:changeme@concourse-db:5432/concourse?sslmode=disable
    dns:
      - 8.8.8.8
      - 8.8.4.4
    restart: on-failure:10

  concourse-worker:
    image: concourse/concourse
    privileged: true
    command: worker
    depends_on: [keys]
    volumes: ['worker-keys:/concourse-keys']
    environment:
      CONCOURSE_TSA_HOST: concourse-web
      CONCOURSE_GARDEN_ADDRESS: concourse-worker
      CONCOURSE_BAGGAGECLAIM_ADDRESS: concourse-worker
      CONCOURSE_GARDEN_FORWARD_ADDRESS: concourse-worker
      CONCOURSE_BAGGAGECLAIM_FORWARD_ADDRESS: concourse-worker
      CONCOURSE_GARDEN_DNS_SERVER: 8.8.8.8
    dns:
      - 8.8.8.8
      - 8.8.4.4
    restart: on-failure:10

  keys:
    build: .
    volumes:
      - web-keys:/keys/web
      - worker-keys:/keys/worker

volumes:
  database:    { external: { name: concourse-db } }
  web-keys:    { external: { name: concourse-web-keys } }
  worker-keys: { external: { name: concourse-worker-keys } }

Dockerfile

FROM alpine:latest

RUN apk update && apk upgrade && \
    apk add --no-cache \
    openssh

RUN mkdir -p /keys/web /keys/worker

CMD ssh-keygen -t rsa -f /keys/web/tsa_host_key -N '' && \
  ssh-keygen -t rsa -f /keys/web/session_signing_key -N '' && \
  ssh-keygen -t rsa -f /keys/worker/worker_key -N '' && \
  cp /keys/worker/worker_key.pub /keys/web/authorized_worker_keys && \
  cp /keys/web/tsa_host_key.pub /keys/worker

run-command.sh

docker volume create --name concourse-db
docker volume create --name concourse-web-keys
docker volume create --name concourse-worker-keys
DOCKERHOST=192.168.56.51 docker-compose up

Ha! It works! if you add the line:

      CONCOURSE_GARDEN_DNS_SERVER: 8.8.8.8

@deitch... thanks for the pointers. It worked for me. Just for others that stumble on this as well (+ future me ;)), this should go in the environment section of the concourse-worker

...
  concourse-worker:
    image: concourse/concourse
    privileged: true
    command: worker
    volumes: ["./keys/worker:/concourse-keys"]
    environment:
      CONCOURSE_TSA_HOST: concourse-web
      CONCOURSE_GARDEN_DNS_SERVER: 8.8.8.8

this works!
i tried before with adding dns config to concourse-worker, but looks like concourse-web also needs it.

... maybe the extra worker envs did the trick:

      CONCOURSE_GARDEN_ADDRESS: concourse-worker
      CONCOURSE_BAGGAGECLAIM_ADDRESS: concourse-worker
      CONCOURSE_GARDEN_FORWARD_ADDRESS: concourse-worker
      CONCOURSE_BAGGAGECLAIM_FORWARD_ADDRESS: concourse-worker

using "regular" volume mounts (no volume containers).

👍