VagrantFile for automating Kubernetes Setup

VagrantFile

# -*- mode: ruby -*-
# vi: set ft=ruby :

# Vagrantfile API/syntax version. Don't touch unless you know what you're doing!
VAGRANTFILE_API_VERSION = "2"
Vagrant.require_version ">= 1.6.0"

# K8s Master Nodes
M_NODES = ENV['M_NODES'] || 1

# K8s Minion Nodes
H_NODES = ENV['H_NODES'] || 2

# Master node Memory & CPUs
M_MEM = ENV['M_MEM'] || 512
M_CPUS = ENV['M_CPUS'] || 1

# Minion Host Memory & CPUs
H_MEM = ENV['H_MEM'] || 1024
H_CPUS = ENV['H_CPUS'] || 1

#Local Variables
master_ip_address = %Q(ifconfig | grep -oP "inet addr:\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}" | grep -oP "\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}" | tail -n 2 | head -n 1)
get_master_ip_address = ""
token = "a5f0cb.caa312d12724203d"

# Generic installer script common for server(s) & client(s)
# This expects arguments that provide runtime values
$installer = <<SCRIPT
#!/bin/bash

echo Will run the common installer script ...

# Update apt and get dependencies
sudo apt-get update
sudo apt-get install -y unzip curl wget

# Install docker and K8s
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
cat <<EOF > /etc/apt/sources.list.d/kubernetes.list
deb http://apt.kubernetes.io/ kubernetes-xenial main
EOF
apt-get update
# Install docker if you don't have it already.
apt-get install -y docker.io
apt-get install -y kubelet kubeadm kubectl kubernetes-cni

SCRIPT


$kubeadminit = <<SCRIPT
#!/bin/bash
echo Will run the kubeadm init script ...
kubeadm init --api-advertise-addresses=$1 --token=$2
SCRIPT

#Will be used in coming revisions
#$kubeadmjoin = <<SCRIPT
#!/bin/bash
#echo Will run the kubeadm join script ...
#kubeadm join --token=$1 $2
#SCRIPT

required_plugins = %w(vagrant-cachier vagrant-triggers)

required_plugins.each do |plugin|
  need_restart = false
  unless Vagrant.has_plugin? plugin
    system "vagrant plugin install #{plugin}"
    need_restart = true
  end
  exec "vagrant #{ARGV.join(' ')}" if need_restart
end


def configureVM(vmCfg, hostname, cpus, mem)

  vmCfg.vm.box = "ubuntu/xenial64"
  
  vmCfg.vm.hostname = hostname
  vmCfg.vm.network "private_network", type: "dhcp"

  
  #Adding Vagrant-cachier
  if Vagrant.has_plugin?("vagrant-cachier")
     vmCfg.cache.scope = :machine
     vmCfg.cache.enable :apt
     vmCfg.cache.enable :gem
     #To fix the apt permission issue.
     vmCfg.cache.synced_folder_opts = {owner: "_apt", group: "_apt"}
  end
  
  # Set resources w.r.t Virtualbox provider
  vmCfg.vm.provider "virtualbox" do |vb|
    vb.memory = mem
    vb.cpus = cpus
    vb.customize ["modifyvm", :id, "--cableconnected1", "on"]
  end
  
  # Script will make some directories before installation procedure
  vmCfg.vm.provision "shell", inline: $installer, privileged: true
  
  return vmCfg
end

# Entry point of this Vagrantfile
Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|


  # K8s Master related only !!
  1.upto(M_NODES.to_i) do |i|
    hostname = "master-%02d" % [i]
    cpus = M_CPUS
    mem = M_MEM
    
    config.vm.define hostname do |vmCfg|
      vmCfg = configureVM(vmCfg, hostname, cpus, mem)
      vmCfg.vm.provision :shell, inline: "echo Setting up the Master using IPAdress: $1", :args => "`#{master_ip_address}`"
      vmCfg.vm.provision :shell, inline: "echo Setting up the Master using Token: $1", :args => "#{token}"
      vmCfg.vm.provision :shell, inline: $kubeadminit, :args => "`#{master_ip_address}` #{token}", privileged: true
    end     
  end
  
  # K8s Host related only !!
  1.upto(H_NODES.to_i) do |i|
    hostname = "host-%02d" % [i]
    cpus = H_CPUS
    mem = H_MEM
    
    config.vm.define hostname do |vmCfg|
      vmCfg = configureVM(vmCfg, hostname, cpus, mem)
      
      #We want to run this only when the VM is first provisioned and get the Master IP to join the cluster
      vmCfg.vm.provision :trigger, :force => true, :stdout => true, :stderr => true do |trigger|
         trigger.fire do
            master_hostname = "master-01"
            get_ip_address = %Q(vagrant ssh #{master_hostname}  -c 'ifconfig | grep -oP "inet addr:\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}" | grep -oP "\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}" | tail -n 2 | head -n 1')       
            get_master_ip_address = `#{get_ip_address}`
            info"Getting the Master IP to join the cluster..."
            if get_master_ip_address == ""
               info"The Kubernetes Master is down, bring it up and manually run:"
               info"kubeadm --token=<token> <master_ip_address>"
               info"in order to join the cluster."
            else
               info"Setting up the Minion using IPAddress: #{get_master_ip_address}"
               info"Setting up the Minion using Token: #{token}"
               @machine.communicate.sudo("kubeadm join --token=#{token} #{get_master_ip_address.strip}")
            end  
         end
      end      
    end
  end
end