Put backpressure between producers and workers

import { Duration, Stack, StackProps } from 'aws-cdk-lib';
import * as apigateway from 'aws-cdk-lib/aws-apigateway';
import * as athena from 'aws-cdk-lib/aws-athena';
import * as bedrock from 'aws-cdk-lib/aws-bedrock';
import * as budgets from 'aws-cdk-lib/aws-budgets';
import * as cloudfront from 'aws-cdk-lib/aws-cloudfront';
import * as origins from 'aws-cdk-lib/aws-cloudfront-origins';
import * as cloudtrail from 'aws-cdk-lib/aws-cloudtrail';
import * as cloudwatch from 'aws-cdk-lib/aws-cloudwatch';
import * as dynamodb from 'aws-cdk-lib/aws-dynamodb';
import * as ecs from 'aws-cdk-lib/aws-ecs';
import * as patterns from 'aws-cdk-lib/aws-ecs-patterns';
import * as events from 'aws-cdk-lib/aws-events';
import * as targets from 'aws-cdk-lib/aws-events-targets';
import * as glue from 'aws-cdk-lib/aws-glue';
import * as iam from 'aws-cdk-lib/aws-iam';
import * as kms from 'aws-cdk-lib/aws-kms';
import * as lambda from 'aws-cdk-lib/aws-lambda';
import * as sources from 'aws-cdk-lib/aws-lambda-event-sources';
import * as s3 from 'aws-cdk-lib/aws-s3';
import * as secretsmanager from 'aws-cdk-lib/aws-secretsmanager';
import * as sqs from 'aws-cdk-lib/aws-sqs';
import { Construct } from 'constructs';

export class PatternStack extends Stack {
  constructor(scope: Construct, id: string, props?: StackProps) {
    super(scope, id, props);

    const dlq = new sqs.Queue(this, 'DeadLetterQueue');
    const queue = new sqs.Queue(this, 'WorkQueue', {
      visibilityTimeout: Duration.seconds(90),
      deadLetterQueue: { queue: dlq, maxReceiveCount: 5 },
    });
    const worker = new lambda.Function(this, 'Worker', {
      runtime: lambda.Runtime.NODEJS_20_X,
      handler: 'index.handler',
      code: lambda.Code.fromAsset('worker'),
      reservedConcurrentExecutions: 10,
    });
    worker.addEventSource(new sources.SqsEventSource(queue, { batchSize: 10, reportBatchItemFailures: true }));
  }
}