def sns?
      json_body.is_a?(Hash) && (%w[Message Type TopicArn MessageId] - json_body.keys).empty?
    end
def sns?
      json_body.is_a?(Hash) && (%w[Message Type TopicArn MessageId] - json_body.keys).empty?
    end
Just because a message was recieved via SQS, doesn't mean it was originally broadcast via SNS
 @return [Boolean] Was the message broadcast via SNS?