queue aws HowTo

How To: Using @quatrain/queue-aws

This guide highlights specific features of the SQS adapter.

Table of Contents

1. Long Polling
2. Message Deletion

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1. Long Polling

When you call listen() using the SQS adapter, it automatically utilizes long polling (up to 20 seconds) to reduce the number of empty API requests and lower costs.

import { Queue } from '@quatrain/queue'

async function consume() {
    const queue = Queue.getAdapter('sqs')
    
    // This will open a long-polling connection to the specified queue URL
    await queue.listen('MyQueueTopic', async (msg) => {
        console.log('Received SQS message:', msg)
        return true
    })
}

2. Message Deletion

In SQS, messages must be explicitly deleted using their ReceiptHandle after processing. The listen() wrapper handles this automatically: if your handler returns true (or a truthy value, or resolves successfully), the adapter will send the DeleteMessageCommand for you. If it throws an error, the message remains hidden until the visibility timeout expires, after which it becomes available again.