Rails docker

docker-compose.yml

version: '3'
services:
  db:
    image: postgres:latest
    ports:
      - "5432"
    environment:
      POSTGRES_PASSWORD: whatever
  web:
    build: .
    volumes:
      - .:/my_app
    depends_on:
      - db
    links:
      - db
    environment:
      RACK_ENV: development
      RAILS_ENV: development
      DB_HOST: db
      DB_USERNAME: postgres
      DB_PASSWORD: whatever
    command: bundle exec rails s -p 3000 -b '0.0.0.0'
    ports:
      - "3000:3000"

Dockerfile

FROM ruby:2.4.1

RUN apt-get update -qq && apt-get install -y build-essential

# install nodejs : https://nodejs.org/en/download/package-manager/#debian-and-ubuntu-based-linux-distributions
RUN curl -sL https://deb.nodesource.com/setup_7.x | bash - && apt-get install -y nodejs

# for postgresql
RUN apt-get install -y libpq-dev

# set env, encoding change might be necessary for some projects
ENV LANG C.UTF-8
ENV LC_ALL C.UTF-8
ENV LANGUAGE C.UTF-8

# create app directory
ENV APP_HOME /my_app
RUN mkdir $APP_HOME
WORKDIR $APP_HOME

# bundle install
ADD Gemfile* $APP_HOME/
RUN bundle install

# add required local files (example npm modules)
ADD package.json $APP_HOME/
RUN npm install
VOLUME $APP_HOME/node_modules

ADD . $APP_HOME