Docker dev environment for Ruby on Rails

docker-compose.yml

version: '3.2'
services:
  db:
    image: postgres

  web:
    build: .
    volumes:
      - type: bind
        source: .
        target: /app
    ports:
      - "3000:3000"
    depends_on:
      - db
    command:
      - ./run.sh

Dockerfile

# Ruby on Rails Development Environment
FROM ruby:2.5.0

# Set up Linux
RUN apt-get update
RUN apt-get install -y build-essential inotify-tools libpq-dev nodejs postgresql-client

WORKDIR /app
EXPOSE 3000

run.sh

#!/bin/sh
set -e

# Ensure the app's dependencies are installed
echo "bundle install --without=production..."
bundle install --without=production

# Wait for Postgres to become available.
echo "Checking for Postgres..."
until psql -h db -U "postgres" -c '\q' 2>/dev/null; do
  >&2 echo "Postgres is unavailable - sleeping"
  sleep 1
done
echo "Postgres is available: continuing with database setup..."

# Potentially Set up the database
echo "bundle exec rake db:setup..."
bin/rails db:setup

# Start the web server
echo "bin/rails s -p 3000 -b '0.0.0.0'..."
bin/rails s -p 3000 -b '0.0.0.0'