def parse_event(sqs_message)
    JSON.parse(sqs_message.body) => Hash => parsed_sqs_body
    parsed_sqs_body["Message"] => String => raw_sns_message

    JSON.parse(raw_sns_message) => Hash => parsed_sns_message
    parsed_sns_message["AutoScalingGroupName"] => String => asg
    parsed_sns_message["EC2InstanceId"] => String => instance_id
    parsed_sns_message["Event"] => String => event

    Environment.where(autoscaling_group: asg).pick(:environment_name) => String => environment_name

    [ event, { environment_name: environment_name, instance_id: instance_id } ]
  rescue NoMatchingPatternError
    nil
  rescue JSON::ParserError => e
    Rails.logger.error "Failed to parse message: #{e.message}"
    nil
  end