Restore local DB with backup from S3

Restore Local

# frozen_string_literal: true

require 'rubygems/package'
require 'zlib'

namespace :maintenance do
  desc 'Restore local with remote backup'
  task restore_local: :environment do
    lambda do
      return unless Rails.env.development?

      logger      = Logger.new(STDOUT)
      db_config   = Rails.configuration.database_configuration[Rails.env]

      Bundler.with_unbundled_env do
        logger.info "=================================================="
        logger.info "Getting DB from S3"
        logger.info "=================================================="
        
        `unset NODE_OPTIONS`

        logger.info "[1/11] Downloading latest backup onto disk"
        downloaded_file_path = download_from_s3
        tmp_dir              = Rails.root.join('tmp','backups','latest').to_s

        logger.info "[2/11] Unzipping archive"
        Dir.mkdir(tmp_dir) unless File.exists?(tmp_dir)

        unzip_file(downloaded_file_path, tmp_dir)

        return unless downloaded_file_path.present?

        logger.info "[3/11] Set env to development"
        `bin/rails db:environment:set RAILS_ENV=development`

        logger.info "[4/11] Drop databases"
        Rake::Task['db:drop'].invoke

        logger.info "[5/11] Re-create databases"
        Rake::Task['db:create'].invoke

        logger.info "[6/11] Mounting backup on local database"
        `pg_restore --clean --verbose --no-acl --no-owner -h localhost -d #{db_config["database"]} -F d #{tmp_dir}`

        logger.info "[7/11] Cleaning up downloads"
        `rm #{downloaded_file_path}`
        `rm -rf #{tmp_dir}`

        logger.info "[8/11] DB Migrate"
        `bin/rails db:migrate`
        Rake::Task['dev:reset_passwords'].invoke

        logger.info "[9/11] Reset Passwords"
        Rake::Task['features:seed'].invoke
        Flipper.features.each(&:enable)

        logger.info "[10/11] Remove Card Authorizations"
        Wallet::CardAuthorization.destroy_all
        BankAccount.destroy_all

        logger.info "[11/11] Masking Data"
        Rake::Task['dev:mask_data'].invoke

        logger.info "DONE 🔥"
      end
    end.call
  end

  private

  def download_from_s3
    bucket    = Aws::S3::Bucket.new("ubuntu-rewards-production-database-backups")
    items     = []
    bucket.objects.each {|o| items << o }

    latest    = items.sort_by {|c| c.last_modified }.last
    file_path = Rails.root.join('tmp', 'backups', 'latest.tar.gz')

    return file_path if File.exists?(file_path)

    return file_path.to_s if latest.download_file(file_path, { mode: 'auto' })
      
    false
  end

  def unzip_file (file, destination)
    tar_long_link = '././@LongLink'
    tar_gz_archive = file

    Gem::Package::TarReader.new( Zlib::GzipReader.open tar_gz_archive ) do |tar|
      dest = nil
      tar.each do |entry|
        if entry.full_name == tar_long_link
          dest = File.join destination, entry.read.strip
          next
        end
        dest ||= File.join destination, entry.full_name
        if entry.directory?
          File.delete dest if File.file? dest
          FileUtils.mkdir_p dest, :mode => entry.header.mode, :verbose => false
        elsif entry.file?
          FileUtils.rm_rf dest if File.directory? dest
          File.open dest, "wb" do |f|
            f.print entry.read
          end
          FileUtils.chmod entry.header.mode, dest, :verbose => false
        elsif entry.header.typeflag == '2' #Symlink!
          File.symlink entry.header.linkname, dest
        end
        dest = nil
      end
    end
  end
end