def update_stack(params)
      unless stack_exists?(@stack_name)
        puts "Cannot update a stack because the #{@stack_name} does not exists."
        return
      end
      exist_unless_updatable(stack_status(@stack_name))

      message = "Updating #{@stack_name} stack"
      error = nil
      if @options[:noop]
        message = "NOOP #{message}"
      else
        diff.run if @options[:diff]
        preview.run if @options[:preview]
        are_you_sure?(:update)

        if @options[:change_set] # defaults to this
          message << " via change set: #{preview.change_set_name}"
          change_set_update
        else
          standard_update(params)
        end
      end
      puts message unless @options[:mute] || error
    end
def update_stack(params)
      unless stack_exists?(@stack_name)
        puts "Cannot update a stack because the #{@stack_name} does not exists."
        return
      end
      exist_unless_updatable(stack_status(@stack_name))

      message = "Updating #{@stack_name} stack"
      error = nil
      if @options[:noop]
        message = "NOOP #{message}"
      else
        diff.run if @options[:diff]
        preview.run if @options[:preview]
        are_you_sure?(:update)

        if @options[:change_set] # defaults to this
          message << " via change set: #{preview.change_set_name}"
          change_set_update
        else
          standard_update(params)
        end
      end
      puts message unless @options[:mute] || error
    end
aws cloudformation update-stack --stack-name prod-hi-123456789 --parameters file://output/params/prod-hi-123456789.json --template-body file://output/prod-hi.json