Auto Scaling examples using SDK for Ruby

require 'aws-sdk-autoscaling'
require 'logger'

# AutoScalingManager is a class responsible for managing AWS Auto Scaling operations
# such as listing all Auto Scaling groups in the current AWS account.
class AutoScalingManager
  def initialize(client)
    @client = client
    @logger = Logger.new($stdout)
  end

  # Gets and prints a list of Auto Scaling groups for the account.
  def list_auto_scaling_groups
    paginator = @client.describe_auto_scaling_groups
    auto_scaling_groups = []
    paginator.each_page do |page|
      auto_scaling_groups.concat(page.auto_scaling_groups)
    end

    if auto_scaling_groups.empty?
      @logger.info('No Auto Scaling groups found for this account.')
    else
      auto_scaling_groups.each do |group|
        @logger.info("Auto Scaling group name: #{group.auto_scaling_group_name}")
        @logger.info("  Group ARN:             #{group.auto_scaling_group_arn}")
        @logger.info("  Min/max/desired:       #{group.min_size}/#{group.max_size}/#{group.desired_capacity}")
        @logger.info("\n")
      end
    end
  end
end

if $PROGRAM_NAME == __FILE__
  autoscaling_client = Aws::AutoScaling::Client.new
  manager = AutoScalingManager.new(autoscaling_client)
  manager.list_auto_scaling_groups
end