AWS CloudFormation Template dumper

cfn-template-dump.rb

# This script will look for cloudformation stacks on your account and download all the templates for you!
# Author: Gabriel Lett Viviani <http://github.com/gabriellett>
# Make sure you have aws-cli installed and configured on your machine,.

require 'json'
require 'optparse'

options = {}
OptionParser.new do |opts|
  opts.banner = "Usage: cfn-template-dump.rb [options]"

  opts.on('-p', '--profile NAME', 'AWS Profile, defaults to the credentials already set on the machine') { |v| options[:profile] = v }
  opts.on('-r', '--region REGION', 'AWS Region, if none is passed, will search on all regions') { |v| options[:region] = v }
end.parse!

stock_command_sufix = ""
stock_command_sufix += " --profile #{options[:profile]}" if options[:profile]

regions = []

if options[:region]
  regions << options[:region]
else
  regions_result = JSON.parse(`aws ec2 describe-regions`)
  regions_result["Regions"].each do |r|
    regions << r["RegionName"]
  end
end

regions.each do |r|

  puts "Looking for stacks on #{r} ... \n\n"

  stack_list = JSON.parse(`aws cloudformation list-stacks #{stock_command_sufix} --region #{r}`)
  stack_list["StackSummaries"].each do |s|

    stack_status = s['StackStatus']
    stack_name = s['StackName']

    if !stack_status.start_with?('DELETE')
      print "  Creating json for #{stack_name}... "
      template_body = JSON.parse(`aws cloudformation get-template --stack-name #{stack_name} #{stock_command_sufix} --region #{r}`)
      File.open("templates/#{stack_name}.json", 'w') do |f|
        f.write(JSON.pretty_generate(template_body['TemplateBody']))
      end
      puts "Done!"
    end
  end
end