Sqs-quooler NPM

SQS Quooler

:walking::walking::walking::walking: An abstraction of Amazon's SQS SDK. It provides an easier to use interface than that of Amazon's SDK.

Installation

npm install --save sqs-quooler

Usage

Connecting to the queue

Note aws-sdk still needs to be imported. SQS Quooler is just a wrapper.

const { SQS, Credentials } = require('aws-sdk')
const { Queue } = require('sqs-quooler')

const sqs = new SQS({
  region: 'your aws region',
  endpoint: 'your aws endpoint',
  // Credentials can be used with YOPA as below
  // credentials: new Credentials({
  //   accessKeyId: 'x',
  //   secretAccessKey: 'x',
  // }),
})

const myQueue = new Queue({
  sqs,
  endpoint: 'your aws endpoint + queue name',
  concurrency: 1, // MaxNumberOfMessages
})

Pushing items to the queue

myQueue.push (data: any) : Promise

Data sent via .push will be stringified before it's sent to SQS.

myQueue.push({
  data: 'test',
})

Removing items from the queue

myQueue.remove (message: object) : Promise

Message object should have a ReceiptHandle property, to identify the message.

myQueue.remove({
  ...
  ReceiptHandle: 'receipt handle',
  ...
})

Changing message visibility

myQueue.changeMessageVisibility (parameters: object) : Promise

Parameters object should have a ReceiptHandle property, to identify the message, and a VisibilityTimeout property to determine in how many seconds the item will return to the queue.

myQueue.changeMessageVisibility({
  ...
  ReceiptHandle: 'receipt handle',
  VisibilityTimeout: 0, // returns immediately to the queue
  ...
})

Retrieving items from the queue

myQueue.startProcessing (handler: function, options: object) : Promise

Handler function should accept 2 arguments, the first one being the parsed message Body value, and the second one being the whole message object. It will be called once for every message found in the queue (depending on the queue's concurrency).

The options object is optional and accept the following properties:

keepMessages (boolean): To avoid deleting the message after processing it. Default is false.
messageAttributesNames (string array): The value which will be sent to the receiveMessage SQS method at the MessageAttributeNames property. Default value is ['All'].
attributeNames (string array): A list of attributes that need to be returned along with each message, within the Attributes property. Default value is ['All'].

After the handler returns (if it returns a Promise, SQS Quooler will wait for it to resolve), the item is automatically deleted from the queue. If your handler throws an error, or returns a rejected Promise, the item will not be removed from the queue.

myQueue.startProcessing((body, message) => {
  // body: {
  //   data: 'test',
  // }

  // message: {
  //   Body: '{"data":"test"}',
  //   ReceiptHandle: 'receipt handle',
  //   MessageAttributes: {
  //     custom_attribute: {
  //       StringValue: 'custom_attribute value',
  //       StringListValues: [],
  //       BinaryListValues: [],
  //       DataType: 'String'
  //     }
  //   }
  //   ...
  // }
})