A complete Alpine docker-compose Rails workflow with PostgreSQL and Redis

docker-compose.yml

version: "3"

services:
  database:
    image: postgres:11-alpine
    volumes:
      - postgres-data:/var/lib/postgresql/data

  redis:
    image: redis:5-alpine
    volumes:
      - redis-data:/data

  web:
    build:
      context: .
      args:
        WITHOUT_BUNDLE: "yes"
    environment:
      REDIS_URL: redis://redis/
      DB_HOST: database
    ports:
      - "3000:3000"
    volumes:
      - bundle-cache:/usr/local/bundle
      - .:/opt/app
    depends_on:
      - database
      - redis

volumes:
  bundle-cache:
  postgres-data:
  redis-data:

Dockerfile

FROM ruby:2.6-alpine

# Additional runtime facilities provided by the OS.
RUN apk add --no-cache libxml2 libxslt postgresql-libs tzdata
# Tell bundler how to use the OS.
RUN gem install bundler -v '~> 1.17' && \
        bundle config build.nokogiri --use-system-libraries
WORKDIR /opt/app
RUN mkdir -p tmp/pids tmp/cache

ARG WITHOUT_BUNDLE="no"
ARG WITHOUT_GROUPS="development test"

COPY Gemfile Gemfile.lock ./
# A single layer of the bundle installation. If we perform the bundle
# install, it is assumed to be final, so we rip out the development
# libraries.
RUN apk add --no-cache --virtual .bundler-installdeps \
          build-base git libxml2-dev libxslt-dev postgresql-dev && \
        if [ $WITHOUT_BUNDLE = 'no' ]; then \
          bundle install --jobs=3 --retry=3 --without=$WITHOUT_GROUPS && \
          rm -rf /usr/local/bundle/cache && \
          apk del .bundler-installdeps; \
        fi

COPY . ./

ENTRYPOINT ["bundle", "exec"]
CMD ["rails", "server", "-b", "0.0.0.0"]
EXPOSE 3000

Makefile

.PHONY: build build-release bundle bundle-install bundle-update console db-setup db-migrate \
	down exec-shell logs up

default: bundle-install

build: # Build the docker image.
	docker-compose build

build-release: # Build the docker image.
	docker build --no-cache -t example-rails-app .

bundle: bundle-install # Alias of bundle-install

bundle-install: build # Install with bundler
	docker-compose run --rm --entrypoint bundle web install --jobs=3 --retry=3

bundle-update: build # Update with bundler
	docker-compose run --rm --entrypoint bundle web update

console: # Start a rails console
	docker-compose run --rm web rails c

db-setup: # Run rake db:setup
	docker-compose run --rm web rake db:setup

db-migrate: # Run rake db:migrate
	docker-compose run --rm web rake db:migrate

down: # Bring all services down
	docker-compose down

exec-shell: # Exec a shell in the running web container.
	docker-compose exec web sh

logs: # Show the logs from the running containers.
	docker-compose logs

up: # Bring all services up
	docker-compose up -d

That helps me a lot, thanks!