AWS SQS ReceiveMessageCommandOutput sometimes returns undefined Messages property

[shawngrona]

Checkboxes for prior research

• I've gone through Developer Guide and API reference
• I've checked AWS Forums and StackOverflow.
• I've searched for previous similar issues and didn't find any solution.

Describe the bug

When polling, the ReceiveMessageCommandOutput returns undefined for Messages property

Similar issue was described here and fixed/resolved #1394

SDK version number

@aws-sdk/package-name@version, ...

Which JavaScript Runtime is this issue in?

Node.js

Details of the browser/Node.js/ReactNative version

v18

Reproduction Steps

const input = {
        QueueUrl: queueUrl,
        MaxNumberOfMessages: 10,
        WaitTimeSeconds: 2,
      };
const result = await client.send(new ReceiveMessageCommand(input));

Observed Behavior

Actual response:

{
  '$metadata': {
    httpStatusCode: 200,
    requestId: '883ab113-c9bc-5e0f-8508-ef098c0f28cf',
    extendedRequestId: undefined,
    cfId: undefined,
    attempts: 1,
    totalRetryDelay: 0
  }
}

Expected Behavior

Expected response:

{
  '$metadata': {
    httpStatusCode: 200,
    requestId: '883ab113-c9bc-5e0f-8508-ef098c0f28cf',
    extendedRequestId: undefined,
    cfId: undefined,
    attempts: 1,
    totalRetryDelay: 0
  },
 Messages: []
}

Possible Solution

No response

Additional Information/Context

Messages is a required property on the response

[aBurmeseDev]

Hi @shawngrona - thanks for reaching out and sorry to hear that you're seeing this behavior.

I wasn't able to reproduce the reported behavior running the code below. While I'm further investigating, can you quickly verify if this happens intermittently or continuously since you mentioned sometimes it returns undefined Messages? Also please note that Messages is not required property on the response but is expected to return when there's a list of messages and the service sends back 200 response.

code example for receiveMessage

import { SQSClient, ReceiveMessageCommand } from "@aws-sdk/client-sqs";
const client = new SQSClient({
    region: 'us-west-1',
});
const input = { 
  QueueUrl: "https://sqs.us-west-1.amazonaws.com/...", 
  MaxNumberOfMessages: 1,
  WaitTimeSeconds: 10,
  VisibilityTimeout: 5,
};
try {
    const command = new ReceiveMessageCommand(input);
    const response = await client.send(command);
    console.log(response);
} catch (error) {
    console.log(error);
};

Try this code with both sendMessage and receiveMessage

const client = new SQSClient({
    region: 'us-west-1',
});
const receiveCommand = new ReceiveMessageCommand ({ 
    QueueUrl: "https://sqs.us-west-1.amazonaws.com/...", // required
    MaxNumberOfMessages: 1,
    WaitTimeSeconds: 10,
    VisibilityTimeout: 5,
});
const sendCommand = new SendMessageCommand ({
    QueueUrl: "https://sqs.us-west-1.amazonaws.com/...", // required
    MessageBody: "sending SQS message via JS SDK"
})
await client.send(sendCommand)
const response = await client.send(receiveCommand);
console.log(response);

Hope that helps but please let me know if issue persists!
John

[shawngrona]

thanks @aBurmeseDev!

I should have mentioned I'm in a loop when this happens - for example lets say there is only one message in the queue, the first call responds with Messages property the second call succeeds with 200 but Messages is undefined

async doRead(queueUrl, region) {
    const client = new SQSClient({
      region,
      endpoint: queueUrl,
    });
    let gotAll = false;
    let messages = [];
    while (!gotAll) {
      const input = {
        QueueUrl: queueUrl,
        MaxNumberOfMessages: 10,
        WaitTimeSeconds: 2,
        VisibilityTimeout: 10,
      };
      const result = await client.send(new ReceiveMessageCommand(input));
      if (result.Messages.length < 1) {
        gotAll = true;
      } else {
        messages = messages.concat(
          result.Messages.map((message) => ({
            body: JSON.parse(message.Body),
            messageId: message.MessageId,
            receiptHandle: message.ReceiptHandle,
          })),
        );
      }
    }
    return messages;
  }

[aBurmeseDev]

Apologies this fell off my radar. Looking at your code, I think the root cause could be that result.Messages might be undefined when the queue is empty. Here's modified code with proper handling of undefined Messages.

async doRead(queueUrl, region) {
    const client = new SQSClient({
      region,
      endpoint: queueUrl,
    });
    let gotAll = false;
    let messages = [];
    
    while (!gotAll) {
      const input = {
        QueueUrl: queueUrl,
        MaxNumberOfMessages: 10,
        WaitTimeSeconds: 2,
        VisibilityTimeout: 10,
      };
      
      const result = await client.send(new ReceiveMessageCommand(input));
      
      // Check if Messages exists and has items
      if (!result.Messages || result.Messages.length === 0) {
        gotAll = true;
      } else {
        messages = messages.concat(
          result.Messages.map((message) => ({
            body: JSON.parse(message.Body),
            messageId: message.MessageId,
            receiptHandle: message.ReceiptHandle,
          })),
        );
      }
    }
    return messages;
  }

[deepprakash345]

Hey @aBurmeseDev,
I am facing a similar issue. I am also trying to fetch messages in a batch size of 10 in a loop. In the first iteration i get 10 msgs but in the next iteration i don't receive any messages. I can see that there are more than 1k msgs in my sqs.

One observation, if i put a wait statement of around 20 secs in between each iteration of the loop then it seems to work. Does this sdk has some limit of calls in a certain time duration pre-built in its implementation.