Docker Setup for workshop

docker-compose.yml

version: "3.9"
services:
  web:
    build: .
    command: bash -c "bundle && bin/dev"
    ports:
      - "3000:3000"
    volumes:
      - .:/myapp
      - gem_cache:/gems:delegated
    tty: true
    stdin_open: true
    links:
      - redis
  redis:
    image: redis:latest
    ports:
      - "6379:6379"
    volumes:
      - "redis:/data"
volumes:
  gem_cache: {}
  redis:

Dockerfile

# syntax=docker/dockerfile:1
FROM ruby:3.1.2
RUN apt-get update -qq && apt-get install -y sqlite3
WORKDIR /myapp
COPY Gemfile /myapp/Gemfile
COPY Gemfile.lock /myapp/Gemfile.lock
RUN bundle install

# Add a script to be executed every time the container starts.
COPY entrypoint.sh /usr/bin/
RUN chmod +x /usr/bin/entrypoint.sh
ENTRYPOINT ["entrypoint.sh"]
EXPOSE 3000

# Configure the main process to run when running the image
CMD ["rails", "server", "-b", "0.0.0.0"]

entrypoint.sh

#!/bin/bash
set -e

# Remove a potentially pre-existing server.pid for Rails.
rm -f /myapp/tmp/pids/server.pid

# Then exec the container's main process (what's set as CMD in the Dockerfile).
exec "$@"