DEV Community

Cover image for Compare Raw and Wrapped Amazon SNS Messages in Amazon SQS
miruky
miruky

Posted on Edited on

Compare Raw and Wrapped Amazon SNS Messages in Amazon SQS

#aws #sns #sqs #tutorial

Introduction

Hi, I'm miruky.

An Amazon SNS subscription to Amazon SQS can deliver either an SNS notification envelope or the published message body itself. The Raw message delivery setting controls that boundary, and the consumer sees a materially different payload even though both queues receive the same publish.

This Console run connects one Standard topic to two Standard queues. One subscription keeps raw delivery disabled, while the other enables it; a single synthetic JSON message then produces a wrapped body in one queue and the unchanged message in the other.

The exercise uses one SNS publish and a few SQS requests. Current SNS and SQS request pricing and free-tier terms are linked below.

1. Create one topic and two queues

Use the English AWS Console in United States (N. Virginia). The topic, queues, subscriptions, publish, and receives remain in us-east-1.

The English AWS Console shows United States (N. Virginia) before the messaging resources are created.

The header confirms United States (N. Virginia) while the SNS Console is in English. This fixes the Region shared by the topic, subscriptions, queues, and messages.

Open Amazon SNS, choose Topics, and search for miruky-oxsoiimhavlbcyhm. Confirm that no exact match exists, then start creating a Standard topic with that name. Leave delivery-status logging unconfigured so the run does not create a logging role or publish delivery logs.

The SNS creation form shows the generated topic name and Standard type before creation.

The form shows miruky-oxsoiimhavlbcyhm and Standard before the topic is created. Delivery-status logging remains unconfigured for this exercise.

In Amazon SQS, search for the exact names miruky-wpmasjamumxmwsaj and miruky-uqlprtivfyrjaxtz, and stop if either already exists. Otherwise, create both as Standard queues. Keep their default delivery settings and SQS-managed server-side encryption.

The SQS queue list shows the two generated Standard queue names.

The queue list shows miruky-wpmasjamumxmwsaj and miruky-uqlprtivfyrjaxtz as Standard queues. Use miruky-wpmasjamumxmwsaj for wrapped delivery and miruky-uqlprtivfyrjaxtz for raw delivery.

The wrapped-delivery queue will retain the SNS envelope. The raw-delivery queue will receive only the published message body.

2. Subscribe both queues, then change one attribute

Open miruky-wpmasjamumxmwsaj, choose Actions, then Subscribe to Amazon SNS topic. Select miruky-oxsoiimhavlbcyhm from the same-account topic list and save. Repeat for miruky-uqlprtivfyrjaxtz.

Creating the subscriptions from the SQS Console also manages the required queue policy statement. The policy identifies the destination queue and the SNS topic allowed to send to it.

Return to the SNS topic and open its subscriptions. Leave raw delivery disabled for the subscription whose endpoint ARN ends with miruky-wpmasjamumxmwsaj. For the subscription whose endpoint ends with miruky-uqlprtivfyrjaxtz, store the raw-delivery attribute as true and save the change. Check the queue name at the end of each endpoint ARN so you change the intended subscription.

The cropped subscription editor shows raw message delivery enabled before the publish.

The editor shows Enable raw message delivery selected for the raw-target subscription. The wrapped-target subscription remains at its disabled default.

The setting applies to later deliveries. Configure both subscriptions before publishing so the two bodies come from the same SNS message.

3. Prove the comparison starts with an empty queue

Before publishing, open miruky-wpmasjamumxmwsaj, choose Send and receive messages, and complete one polling cycle. Expect zero messages at this point.

The wrapped-delivery queue has no message before the controlled SNS publish.

The receive area remains empty after the polling cycle. This negative control rules out an older queue message before the comparison begins.

4. Publish one controlled JSON message

Choose Publish message on the topic. Leave the subject empty, use identical payloads for all delivery protocols, and enter this message body:

{"orderId":"order-001","status":"ready"}
Enter fullscreen mode Exit fullscreen mode

Enter that JSON on one line so whitespace cannot change the escaped wrapped value. Do not add message attributes. Raw delivery to SQS supports at most ten message attributes, and SNS discards a raw-delivery message with more than ten as a client-side error; attributes are outside this comparison.

The SNS publish form shows the fixed two-field JSON in the identical-payload editor.

The form shows Identical payload for all delivery protocols. and the exact {"orderId":"order-001","status":"ready"} body. The subject and message-attribute inputs are empty for this publish. The single-line body fixes the escaped value expected in the wrapped message.

Choose Publish message and wait for the success confirmation. One publish should fan out to both queue subscriptions.

SNS confirms the publish without exposing the generated message identifier.

The Console reports that the message was published successfully. The generated message ID is omitted from the screenshot.

5. Compare the two SQS bodies

Open miruky-wpmasjamumxmwsaj, choose Send and receive messages, and poll. With raw delivery disabled, the SQS body is an SNS notification JSON document. The original payload appears as a string in the envelope's Message member:

"Message": "{\"orderId\":\"order-001\",\"status\":\"ready\"}"
Enter fullscreen mode Exit fullscreen mode

The Message value is a JSON string inside the larger SNS notification envelope. The complete body also carries an SNS notification type, a message ID, topic ARN, timestamp, signature, certificate URL, and unsubscribe URL. The screenshot shows only the Message field; the other envelope fields are omitted.

A tightly cropped wrapped-message excerpt shows only the escaped fixed Message field.

The cropped excerpt shows Message with the escaped {"orderId":"order-001","status":"ready"} value. The backslashes escape the quotation marks within the JSON string.

Now poll miruky-uqlprtivfyrjaxtz. With raw delivery enabled, SNS strips its metadata and sends the published body as-is:

{"orderId":"order-001","status":"ready"}
Enter fullscreen mode Exit fullscreen mode

The raw-delivery queue body equals the original two-field JSON message.

The raw queue body is exactly {"orderId":"order-001","status":"ready"}. The displayed body text matches the original SNS publish.

The raw queue has no outer Type, TopicArn, Message, signature, or unsubscribe URL fields. Its consumer can parse the order object directly, while the wrapped consumer must parse the SNS envelope and then parse the escaped Message string.

Both destinations are Standard queues, so this comparison proves the body contract, not exactly-once delivery. Standard queues can deliver a duplicate or occasionally change message order; a production consumer still needs idempotent handling regardless of the raw-delivery setting.

Wrap-up

One SNS publish reached both SQS queues. The wrapped SQS body was an SNS notification envelope; the raw SQS body was the original two-field JSON.

Raw delivery reduces envelope parsing when a consumer needs only the published payload. Wrapped delivery retains SNS metadata that can matter to consumers, so the choice belongs in the subscription contract rather than being treated as a cosmetic Console setting.

Thanks for reading this far.

See you in the next one.

Disclosure: This article was written with AI assistance and independently verified against the linked primary sources and observed results.

References

Top comments (0)