Vagrant, VirtualBox, & Docker Lab

This lab will show you how to use Vagrant, VirtualBox, and Docker to automate the creations of development environments. As an example, it creates a Python / Flask / Redis development environment using Vagrant and VirtualBox to set up the Python development environment, and Docker to set up the Redis server.

By creating a Vagrantfile for all of your projects, you can provide developers with an "Instant Development Environment" the runs the same on their machine as every other machine eliminating the excuse "It Works on My Machine!"

Instant Development Environment

This all each developer needs to do to get a consistent development environment to code, debug, and test with:

git clone https://github.com/rofrano/lab-vagrant.git
cd lab-vagrant
vagrant up

Additions to Vagrantfile

The following additions were made to the Vagrantfile to auto provision a complete development environment:

Forward ports from vm to host

config.vm.network "forwarded_port", guest: 5000, host: 5000

Control the vm memory and cpus

config.vm.provider "virtualbox" do |vb|
  vb.memory = "1024"
  vb.cpus = 1
end

Set up development environment

config.vm.provision "shell", inline: <<-SHELL
  sudo apt-get update
  sudo apt-get install -y git python-pip python-dev build-essential
  sudo apt-get -y autoremove
  # Install app dependencies
  cd /vagrant
  sudo pip install -r requirements.txt
  # Prepare Redis data share
  sudo mkdir -p /var/lib/redis/data
  sudo chown vagrant:vagrant /var/lib/redis/data
  # Make vi look nice
  echo "colorscheme desert" > ~/.vimrc
SHELL

Provision Docker containers for Redis

config.vm.provision "docker" do |d|
  d.pull_images "redis:alpine"
  d.run "redis:alpine",
    args: "--restart=always -d --name redis -h redis -p 6379:6379 -v /var/lib/redis/data:/data"
end

Run the Application

Once you have used vagtant up to start the vm use:

vagrant ssh
cd /vagrant
python app.py

You should now be able to test the application with the following URL:

localhost:5000/hits

Every time you access the URL the counter should increase by one.