SQS + S3 Message Bus Adapter

DRY Castore MessageQueue definition using AWS SQS and AWS S3.

This adapter works like the SQS Message Queue Adapter (it actually uses it under the hood), excepts that entry sizes are checked before publishing messages to EventBridge. If they are over the 256KB limit, they are written on a s3 bucket instead, and a message is sent containing a pre-signed URL, as recommended by AWS.

Do not forget to set a lifecycle configuration on your s3 bucket to delete the written objects after the presigned URL has expired to avoid high s3 bills! 🤑

📥 Installation

``bash


npm

npm install @castore/message-queue-adapter-sqs-s3

yarn

yarn add @castore/message-queue-adapter-sqs-s3
`

This package has @castore/core, @aws-sdk/client-sqs (above v3), @aws-sdk/client-s3 (above v3) and @aws-sdk/s3-request-presigner (above v3) as peer dependencies, so you will have to install them as well:

`bash


npm

npm install @castore/core @aws-sdk/client-sqs @aws-sdk/client-s3 @aws-sdk/s3-request-presigner

yarn

yarn add @castore/core @aws-sdk/client-sqs @aws-sdk/client-s3 @aws-sdk/s3-request-presigner
`

👩‍💻 Usage

`ts
import { SQSClient } from '@aws-sdk/client-sqs';
import { S3Client } from '@aws-sdk/client-s3';

import { SQSS3MessageBusAdapter } from '@castore/message-queue-adapter-sqs-s3';

const sqsClient = new SQSClient({});
const s3Client = new S3Client({});

const messageQueueAdapter = new SQSS3MessageQueueAdapter({
queueUrl: 'https://sqs.us-east-1.amazonaws.com/111122223333/my-super-queue',
sqsClient,
s3BucketName: 'my-bucket-name',
s3Client,
// 👇 Optional s3 prefix for temporary data
s3Prefix: 'temporary-storage/',
// 👇 Optional s3 presignature expiration in seconds (defaults to 900)
s3PreSignatureExpirationInSec: 3600
});

// 👇 Alternatively, provide a getter
const messageQueueAdapter = new SQSS3MessageQueueAdapter({
queueUrl: () => process.env.MY_QUEUE_URL,
s3BucketName: () => process.env.MY_BUCKET_NAME
...
});

const appMessageQueue = new NotificationMessageQueue({
...
messageQueueAdapter
})
`

This will directly plug your MessageQueue to SQS and S3 🙌

🤔 How it works

You can read the SQS Message Queue Adapter documentation for regular cases.

When an entry is oversized, its Detail is saved as a JSON object in the provided s3 bucket. It's key is a concatenation of the constructor s3Prefix option, the eventStoreId and aggregateId of the event and the current timestamp:

`ts
const key = 'temporary-storage/POKEMONS/pikachu1/2020-01-01T00:00:00.000Z';
`

If the event is a notification or state-carrying event, the version is also added to the mix:

`ts
// 👇 Date is suffixed by the version
const key = 'temporary-storage/POKEMONS/pikachu1/2020-01-01T00:00:00.000Z#3';
`

On the listeners side, you can use the SQSS3MessageBusMessage TS type to type your argument, and the parseMessage util to fetch the message if it has been uploaded to S3 (it passes it through otherwise):

On the worker side, you can use the SQSS3MessageQueueMessage TS type to type your argument, and the parseBody util to fetch the message if it has been uploaded to S3 (it passes it through otherwise):

`ts
import {
SQSS3MessageQueueMessage,
parseBody,
} from '@castore/message-queue-adapter-sqs-s3';

const appMessagesWorker = async ({ Records }: SQSS3MessageQueueMessage) => {
for (const { body } of Records) {
// 🙌 Correctly typed!
const recordBody = await parseBody(body);
}
};
`

Note that parseBody uses fetch under the hood, so you will have to provide it if your version of node doesn't:

`ts
import fetch from 'node-fetch';

import {
SQSS3MessageQueueMessage,
parseBody,
} from '@castore/message-queue-adapter-sqs-s3';

const appMessagesWorker = async ({ Records }: SQSS3MessageQueueMessage) => {
for (const { body } of Records) {
// 🙌 Correctly typed!
const recordBody = await parseBody(body, { fetch });
}
};
`

🔑 IAM

The publishMessage method requires the sqs:SendMessage IAM permission on the provided SQS queue, as well as the s3:putObject and s3:getObject IAM permissions on the provided s3 bucket at the desired keys (e.g. my-bucket-name/temporary-storage/*).

The parseBody` util doesn't require any permission as the messageURL is pre-signed.