build script for terraform deploys

build.rb

#!/usr/bin/env ruby

require 'optparse'
require 'fileutils'
require 'open3'

options = {
  parallelism: 10,
  init: false
}

OptionParser.new do |parser|
  parser.banner = 'Usage: build [options] TARGET'
  parser.on('-i', '--init', 'Run terraform init (default false)')
  parser.on('-p', '--parallelism [PARALLELISM]', 'Run terraform apply with PARALLELISM, (default 10)', Integer)
  parser.on('-v', '--vault', 'wrap with aws-vault (default false)')
  parser.on('-t', '--tag IMAGE_TAG', 'Run terraform apply with supplied IMAGE_TAG)')
end.parse!(into: options)

raise OptionParser::MissingArgument, 'TARGET' if ARGV.empty?

FileUtils.cd('terraform/docker')

vault = options[:vault] ? "aws-vault exec #{ARGV[0]} --" : ''

env_vars = {
  'TF_VAR_github_token' => ENV['BUNDLE_GITHUB__COM'] || `op read "<some 1pass cred>"`
}

env_vars.merge!('<some project>_image_tag' => options[:tag]) if options[:tag]

if options[:init]
  FileUtils.rm_rf(['.terraform', 'terraform.lock.hcl'])
  cmd = [vault, 'terraform init'].join(' ')
  puts "running: '#{cmd}'"
  Open3.popen3(env_vars, cmd) do |_stdin, stdout, stderr, wait_thread|
    stdout_reader = Thread.new { stdout.each { |line| puts line } }
    stderr_reader = Thread.new { stderr.each { |line| puts line } }
    stdout_reader.join
    stderr_reader.join
    wait_thread.join
  end
end

cmd = [vault, "terraform apply -auto-approve -parallelism=#{options[:parallelism]}"].join(' ')

puts "running: '#{cmd}'"
Open3.popen3(env_vars, cmd) do |_stdin, stdout, stderr, wait_thread|
  stdout_reader = Thread.new { stdout.each { |line| puts line } }
  stderr_reader = Thread.new { stderr.each { |line| puts line } }
  stdout_reader.join
  stderr_reader.join
  wait_thread.join
end