(aws-core): Aspects are not visited if added via module

[joshskinner-vertex]

What is the problem?

We have been migrating to CDK v2 and noticed our Aspects were not visited during a cdk synth. Tracking it down, we found that Aspects are visited if they are added in the app code but remain unvisited if added in library code.

Reproduction Steps

Overview of Steps

• create mylib and myapp projects in each CDK Framework version
• see expected output in a CDK v1 (1.116.0) project set
• see unexpected output in a migrated CDK v2 (2.12.0) project set

myapp (v1)

./v1/myapp/bin/myapp.ts

import 'source-map-support/register';
import * as cdk from '@aws-cdk/core';
import { MyStack } from '../lib/myapp-stack';

const app = new cdk.App();
new MyStack(app);

./v1/myapp/lib/myapp-stack.tst

import * as cdk from '@aws-cdk/core';
import {
  MyAspect, MyLibStack
} from "mylib";

export class MyStack extends MyLibStack {
  constructor(scope: cdk.Construct) {
    super(scope);
    cdk.Aspects.of(this).add(new MyAspect(this, 'MyStack'));
  }
}

mylib (v1)

./v1/mylib/lib/index.ts

import * as cdk from '@aws-cdk/core';

export class MyLibStack extends cdk.Stack {
  constructor(scope: cdk.Construct) {
    super(scope);
    cdk.Aspects.of(this).add(new MyAspect(this, 'MyLibStack'));
  }
}

export class MyAspect implements cdk.IAspect {
    private readonly whoami: string;

    public constructor(scope: cdk.Construct, whoami: string) {
      this.whoami = whoami;
      console.log(this.whoami + ' MyAspect constructor: ' + scope.node.path);
    }
  
    public visit(node: cdk.IConstruct): void {
      console.log(this.whoami + ' visit: ' + node.node.path);
    }
}

Expected output of cdk synth -q:

MyLibStack MyAspect constructor: Default
MyStack MyAspect constructor: Default
MyLibStack visit: Default
MyStack visit: Default

myapp (v2)

./v2/myapp/bin/myapp.ts

import 'source-map-support/register';
import * as cdk from 'aws-cdk-lib';
import { MyStack } from '../lib/myapp-stack';

const app = new cdk.App();
new MyStack(app);

./v2/myapp/lib/myapp-stack.tst

import * as cdk from 'aws-cdk-lib';
import {
  MyAspect, MyLibStack
} from "mylib";
import { Construct } from 'constructs';

export class MyStack extends MyLibStack {
  constructor(scope: Construct) {
    super(scope);
    cdk.Aspects.of(this).add(new MyAspect(this, 'MyStack'));
  }
}

mylib (v2)

./v2/mylib/lib/index.ts

import * as cdk from 'aws-cdk-lib';
import { Construct, IConstruct } from 'constructs';

export class MyLibStack extends cdk.Stack {
  constructor(scope: Construct) {
    super(scope);
    cdk.Aspects.of(this).add(new MyAspect(this, 'MyLibStack'));
  }
}

export class MyAspect implements cdk.IAspect {
    private readonly whoami: string;

    public constructor(scope: Construct, whoami: string) {
      this.whoami = whoami;
      console.log(this.whoami + ' MyAspect constructor: ' + scope.node.path);
    }
  
    public visit(node: IConstruct): void {
      console.log(this.whoami + ' visit: ' + node.node.path);
    }
}

Unexpected output of cdk synth -q:

MyLibStack MyAspect constructor: Default
MyStack MyAspect constructor: Default
MyStack visit: Default

What did you expect to happen?

Expected to see identical output from the cdk synth -q commands of the v1 and v2 apps.

For both projects, specifically,

MyLibStack MyAspect constructor: Default
MyStack MyAspect constructor: Default
MyLibStack visit: Default
MyStack visit: Default

What actually happened?

The following message was not seen.

MyLibStack visit: Default

Meaning, the Aspect added to the Stack in the library code was not visited during the cdk synth

CDK CLI Version

2.12.0 (build c9786db)

Framework Version

2

Node.js Version

v14.17.1

OS

Mac OSX 12.1

Language

Typescript

Language Version

~3.9.7

Other information

For these reproducible steps, I used cdk init lib --language typescript and cdk init app --language typescript to generate the both sets of projects. I then edited the v1 projects to use CDK v1 by changing the package.json dependencies, removing the node_modules folders, migrating the code itself, and running yarn build and link. I can provide the entire directory structure if it would help.

[RichiCoder1]

I've also run into this. Worth noting too that I think this wasn't introduced with v2 but at some point later into v2's lifecycle. This was working after we migrated to v2, but broke at some point during a v2 upgrade.

[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.