Dockerfile and docker-compose for Rails Development

docker-compose.yml

version: '3.7'
services:
  rails: &rails
    build:
      context: .
      dockerfile: ./dockerfiles/Dockerfile-dev
      args:
        RUBY_VERSION: '3.0.0'
        BUNDLER_VERSION: '2.2.3'
        uid: $uid
        gid: $gid
        PORT: $PORT
    environment: &environment
      REDIS_URL: $REDIS_URL
      PORT: $PORT
    ports:
      - $PORT:$PORT

  dev: &dev
    <<: *rails
    tty: true
    stdin_open: true
    command: bundle exec rails s -p 3000 -b '0.0.0.0'
    tty: true
    stdin_open: true
    user: $uid:$gid
    working_dir: '/var/www'
    restart: on-failure
    volumes:
      - type: bind
        source: ./
        target: /var/www
    ports:
      - $PORT:$PORT
    environment:
      RAILS_ENV: "development"
      DB_DEV_HOST: "db_dev"
      REDIS_URL: $REDIS_URL  
      POSTGRES_USER: $POSTGRES_USER
    depends_on:
      - db_dev
      - redis
      - sidekiq

  test: &test
    <<: *dev
    working_dir: '/var/www'
    user: $uid:$gid
    environment:
      REDIS_URL: 'redis://redis:6379/0'
      RAILS_ENV: "test"
      CODECOV: 'true'
    depends_on:
      - redis

  redis:
    image: redis

  sidekiq:
    build: 
      context: .
      dockerfile: ./dockerfiles/Dockerfile-dev
    depends_on:
      - 'db_dev'
      - 'redis'
    command: bundle exec sidekiq
    volumes:
      - type: bind
        source: ./
        target: /var/www
    environment:
      REDIS_URL_SIDEKIQ: $REDIS_URL 

  db: &db
    image: postgres:latest
    restart: always
    ports:
      - 5432:5432

  db_dev:
    <<: *db
    environment:
      POSTGRES_USER: "postgres"
      POSTGRES_DATABASE: "maildigest_development"
      POSTGRES_HOST_AUTH_METHOD: trust

Dockerfile-dev

ARG RUBY_VERSION
FROM ruby:$RUBY_VERSION

ARG BUNDLER_VERSION
ARG uid
ARG gid
ARG PORT
ARG REDIS_URL

# set some env variables
ENV REDIS_URL=${REDIS_URL}
ENV PORT=${PORT}

# The qq is for silent output in the console
RUN apt-get update -qq && \
  apt-get install -y build-essential openssl libssl-dev nodejs less vim libsasl2-dev

#RUN  curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - &&\
#  tee /etc/apt/sources.list.d/yarn.list &&\
#  apt-get update -qq && apt-get install -y yarn

# Creating a user to overcome the fact that on Linux
# Docker runs as a daemon with root permissions and
# takes ownership of your mounted folder
RUN groupadd -g $gid webuser && \
  useradd -l -ms /bin/bash -u $uid -g $gid webuser

# Sets the path where the app is going to be installed

ENV WORK_ROOT /var
ENV RAILS_ROOT $WORK_ROOT/www/
ENV LANG C.UTF-8
ENV GEM_HOME $WORK_ROOT/bundle
ENV BUNDLE_BIN $GEM_HOME/gems/bin
ENV PATH $GEM_HOME/bin:$BUNDLE_BIN:$PATH

RUN gem install bundler -v $BUNDLER_VERSION && \
  mkdir -p $RAILS_ROOT && mkdir -p /var/www/tmp

# This is given by the Ruby Image.
# This will be the de-facto directory that
# all the contents are going to be stored.
RUN chown -R $uid:$gid $GEM_HOME &&\
  bundle config --path=$GEM_HOME

WORKDIR $RAILS_ROOT

# We are copying the Gemfile first, so we can install
# all the dependencies without any issues
# Rails will be installed once you load it from the Gemfile
# This will also ensure that gems are cached and onlu updated when
# they change.
COPY Gemfile ./
COPY Gemfile.lock ./

RUN chown -R webuser:webuser $RAILS_ROOT

USER webuser
# Installs the Gem File.
RUN bundle install

# We copy all the files from the current directory to our
# /app directory
# Pay close attention to the dot (.)
# The first one will select ALL The files of the current directory,
# The second dot will copy it to the WORKDIR!
COPY . $RAILS_ROOT