Dockfile Rails 6

docker-compose.yml

version: '3'
services:
  web:
    build: .
    command: bash -c "rm -f tmp/pids/server.pid && bundle exec rails s -p 3000 -b '0.0.0.0' && bundle exec clockwork ./config/clock.rb"
    volumes:
      - .:/wfh-tracker
    ports:
      - "3000:3000"
    environment:
      - RAILS_ENV=development

Dockerfile

FROM ruby:2.6.0
RUN printf "deb http://archive.debian.org/debian/ jessie main\ndeb-src http://archive.debian.org/debian/ jessie main\ndeb http://security.debian.org jessie/updates main\ndeb-src http://security.debian.org jessie/updates main" > /etc/apt/sources.list
RUN apt-get update -qq && apt-get install -y nodejs


ENV APP_PATH=/wfh-tracker
RUN mkdir $APP_PATH
WORKDIR $APP_PATH
COPY Gemfile "${APP_PATH}/Gemfile"
COPY Gemfile.lock "${APP_PATH}/Gemfile.lock"
RUN bundle install

COPY . /app


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

# Start the main process. 
# Keep reading to see why we commented this line out!
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 /app/tmp/pids/server.pid

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