New Docker, Rails, Postgres app in one bash script

rails_docker_starter.sh

#This script will create the required Dockerfile, docker-compose.yml, Gemfile, etc. and create a new rails app (using postgres)
#BEWARE! It will overwrite any existing files in the folder including Dockerfile, docker-compose.yml, and README.md
#the databses will be called "myapp_development", and "myapp_test"
cat << EOF > Dockerfile
FROM ruby:latest
#USER $USER

#make sure we don't get tripped up by any inherited proxies
#RUN unset HTTP_PROXY
#RUN unset HTTPS_PROXY

#NOTE!!!!!! If you're behind a proxy, you'll need to set it explicitly like so
#ENV http_proxy=http://myproxy.com:80
#ENV https_proxy=http://myproxy.com:80

RUN apt-get update && apt-get install -y build-essential libpq-dev nodejs vim man postgresql-client


#install latest nodejs to support autoprefixer
RUN curl -sL https://deb.nodesource.com/setup_12.x | bash -
RUN apt-get install -y nodejs

ENV APP_HOME /myapp
RUN mkdir \$APP_HOME
WORKDIR \$APP_HOME

RUN gem install rails

ADD Gemfile* \$APP_HOME/

RUN bundle install
EOF


#create our Gemfile
cat << EOF > Gemfile
source 'https://rubygems.org'
gem 'rails', '5.2.1'
EOF

#I guess we need one of these before we build...
touch Gemfile.lock

# four our database files
mkdir -p tmp/db

#create our docker-compose
cat << EOF > docker-compose.yml
version: '3'
services:
  db:
    image: postgres
    volumes:
      - ./tmp/db:/var/lib/postgresql/data
  web:
    build: .
    command: bundle exec rails s -p 3000 -b '0.0.0.0'
    volumes:
      - .:/myapp
    ports:
      - "3000:3000"
    depends_on:
      - db
EOF

#create the rails site...and populate our Gemfile with the stuff needed by rails
docker-compose run web rails new . --force --database=postgresql

#On linux systems (where Docker must run as root), you'll need to open up permissions on the files created.
#!!!
#sudo chmod -R 777 .

#now build everything (since we now have the right gems in the gemfile)
docker-compose build

#tweak the database config to point to our db container
cat << EOF > config/database.yml
default: &default
  adapter: postgresql
  encoding: unicode
  host: db
  username: postgres
  password:
  pool: 5

development:
  <<: *default
  database: myapp_development


test:
  <<: *default
  database: myapp_test
EOF

#start it up (in the background using &)
docker-compose up &

#wait for the db to appear...
sleep 5

#create the database(s)
docker-compose run web rake db:create


#throw in a Procfile for heroku
cat << EOF > Procfile
#Procfile for heroku
#see https://devcenter.heroku.com/articles/procfile
web: bundle exec rails server -p \$PORT
EOF


#visit!
open http://localhost:3000

#To gracefully shut down, use "docker-compose down"

#to allow web console use from a docker host, add this to env/development.rb
#config.web_console.whitelisted_ips = ['10.0.0.0/8', '172.16.0.0/12', '192.168.0.0/16']