aws_ecs_patterns: ApplicationLoadBalancedFargateService does not allow multiple services to connect to the same load balancer

[bytesnz-doc]

Describe the bug

(Reopening of #24975)

The ApplicationLoadBalancedFargateService and ApplicationLoadBalancedServiceBase classes do not allow for multiple services to be created against the same load balancer. An example repo is https://gitlab.com/bytesnz/fargate-services-fail/-/blob/main/index.ts#L47 based off https://github.com/aws-samples/aws-cdk-examples/tree/main/typescript/application-load-balancer. The cause is a hardcoded name for the listener of PublicListener.

Regression Issue

• Select this option if this issue appears to be a regression.

Last Known Working CDK Version

No response

Expected Behavior

ApplicationLoadBalancedFargateService and ApplicationLoadBalancedServiceBase classes use a unique name for the listener and cdk synth generates that stack correctly and stack is able to be deployed

Current Behavior

cdk synth throws an error

/projects/node_modules/constructs/src/construct.ts:430
      throw new Error(`There is already a Construct with name '${childName}' in ${typeName}${name.length > 0 ? ' [' + name + ']' : ''}`);
            ^
Error: There is already a Construct with name 'PublicListener' in ApplicationLoadBalancer [NZTCSLoadBalancer]
    at Node.addChild (/projects/node_modules/constructs/src/construct.ts:430:13)
    at new Node (/projects/node_modules/constructs/src/construct.ts:71:17)
    at new Construct (/projects/node_modules/constructs/src/construct.ts:482:17)
    at new Resource (/projects/node_modules/aws-cdk-lib/core/lib/resource.js:1:1309)
    at new BaseListener (/projects/node_modules/aws-cdk-lib/aws-elasticloadbalancingv2/lib/shared/base-listener.js:1:1721)
    at new ApplicationListener (/projects/node_modules/aws-cdk-lib/aws-elasticloadbalancingv2/lib/alb/application-listener.js:1:3663)
    at ApplicationLoadBalancer.addListener (/projects/node_modules/aws-cdk-lib/aws-elasticloadbalancingv2/lib/alb/application-load-balancer.js:1:6005)
    at new ApplicationLoadBalancedServiceBase (/projects/node_modules/aws-cdk-lib/aws-ecs-patterns/lib/base/application-load-balanced-service-base.js:1:4013)
    at new ApplicationLoadBalancedFargateService (/projects/node_modules/aws-cdk-lib/aws-ecs-patterns/lib/fargate/application-load-balanced-fargate-service.js:1:864)
    at new BackEnd (/projects/src/stacks/backEnd.ts:79:23)

Reproduction Steps

1. Clone the repo https://gitlab.com/bytesnz/fargate-services-fail
2. Install node dependencies
3. Try to synth or deploy with CDK

Possible Solution

I was wondering if the id could be something like id + 'Listener' instead of 'PublicListener'. Can do a PR for, but there are a few other ids that might need the same treatment.

Additional Information/Context

No response

CDK CLI Version

2.175.1

Framework Version

2.175.1

Node.js Version

22

OS

Ubuntu

Language

TypeScript

Language Version

5.1.6

Other information

No response

[pahud]

Yes, this is a high level L3 construct which is opinionated and may not fit all use cases.

We should explore if we could gracefully build this feature upon the existing construct and not adding breaking changes.

We welcome PRs and please help us prioritize with 👍