SNS serialized JSON Message only shows "default"

Question

Hi,
I have a lambda that inserts a message into a SNS Topic. The topic then gets pushed to a subscribed SQS queue, and triggers a lambda to process and send out an SES email.

**ISSUE**: After the message goes through SNS and SQS and arrives at the lambda trigger, the "**Message**" property does not contain the full serialized JSON string, it gets cut/formatted. I've tried many variations of the below, including this conversation that **goes back to *2014*** here: https://github.com/aws/aws-sdk-js/issues/262

**Topic Message Parameters being inserted into SNS:**

var params = {
    TopicArn: "...",
    MessageStructure: "json",
    Message: JSON.stringify({
      default: "I am the default",
      info: JSON.stringify({data: { message: "hello 123"} })
    }),
    MessageGroupId: "PID-112"
  };

**MESSAGE BODY AFTER GOING THROUGH SNS/QUEUE:**

Records: [
    {
      messageId: '...',
      receiptHandle: '...',
      body: '{
' +
        '  "Type" : "Notification",
' +
        '  "MessageId" : "...",
' +
        '  "TopicArn" : "arn:aws:sns:...",
' +
        '  "Message" : "I am the default",
' +
        '  "Timestamp" : "2022-07-07...",
' +
        '  "UnsubscribeURL" : "...' +
        '}',
      attributes: [Object],
      messageAttributes: {},
      eventSource: 'aws:sqs',
      eventSourceARN: 'arn:aws:sqs:...',
    }
  ]

Thanks,
TS

Accepted Answer

The `Message` property can be a text to send a message to all transport protocols, or a json to send different text for each transport protocol when you set the property `MessageStructure` to json. See the [Publish API](https://docs.aws.amazon.com/sns/latest/api/API_Publish.html).

If you don't define a property for a specific protocol, the information in the `default` property is used. As you are sending to SQS, only the information in the `default` property is being sent and the `info` property doesn't map to any transport protocol, so it isn't sent.

For your use case, don't sent the `MessageStructure` and remove the in object JSON.stringify, as:
```javascript
var params = { TopicArn: "arn:aws:sns:us-east-1:321363201397:sendNotification.fifo", Message: JSON.stringify({ default: "I am the default", info: {data: { message: "hello 123"} } }), MessageGroupId: "PID-112" };
```

SNS serialized JSON Message only shows "default"

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