varnish-backend-conf.rb

varnish-backend-conf.rb

require 'rubygems'
require 'aws-sdk'

AWS.config(
  access_key_id: 'ACCESSKEY',
  secret_access_key: 'SECRETKEY',
  auto_scaling_endpoint: 'autoscaling.eu-west-1.amazonaws.com',
  ec2_endpoint: 'ec2.eu-west-1.amazonaws.com'
)

ec2 = AWS::AutoScaling.new

instances = ec2.groups.flat_map do |group|
  if group.name == 'prod-group'
    group.auto_scaling_instances.map do |instance|
      AWS::EC2::Instance.new(instance.id).private_ip_address
    end
  end
end

nodes_num = 0

instances.each do |instance|
  puts "backend node#{nodes_num.to_s} {
    .host = \"#{instance}\";
    .port = \"8080\";
    .probe = healthcheck;
  }\n"
  nodes_num += 1
end

puts 'director cluster random {'
(0..nodes_num-1).each { |i| puts "{ .backend = node#{i}; .weight = 1; }" }
puts '}'