(ecs): add a service extension interface to ECS services

[misterjoshua]

I'd like ECS services to have an extension interface similar to TaskDefinition.addExtension and ITaskDefinitionExtension.

Use Case

I want to create packaged sets of modifications for ECS services. For instance, I may have a standard set of service discovery options or scaling policies that I want to apply to a service. I would like the option to create these packaged modifications in a way that works on either or both of Fargate and EC2 services.

Proposed Solution

Add an IServiceExtension interface and an addExtension method to BaseService. Users could then implement an IServiceExtension and provide it as a parameter to the service's addExtension method.

class MyStandardScaling implements ecs.IFargateServiceExtension, ecs.IEc2ServiceExtension {
  extend(service: ecs.FargateService | ecs.Ec2Service): void {
    service.autoScaleTaskCount({
      maxCapacity: 100,
      minCapacity: 2,
    }).scaleOnCpuUtilization('Target40', {
      targetUtilizationPercent: 40,
    });
  }
}

service.addExtension(new MyStandardScaling());

Other

• 👋 I may be able to implement this feature request
• ⚠️ This feature might incur a breaking change

---

This is a 🚀 Feature Request

[SoManyHs]

Closing as per comment in #13235

[github-actions]

⚠️COMMENT VISIBILITY WARNING⚠️

Comments on closed issues are hard for our team to see.
If you need more assistance, please either tag a team member or open a new issue that references this one.
If you wish to keep having a conversation with other community members under this issue feel free to do so.