What is the problem?

As of CDKv2, the CustomResourceProvider class significantly changed its API. In v1, you separately instantiated a Lambda function, then created a CustomResourceProvider via CustomResourceProvider.fromLambda(). In v2, CustomResourceProvider now wraps the Lambda on your behalf, and you specify a code directory to bundle. This is done because an __entrypoint__.js is injected into that bundle, that wraps your custom Lambda code. __entrypoint__.js is generated from packages/@aws-cdk/core/lib/custom-resource-provider/nodejs-entrypoint.ts. Line 41 requires your Lambda handler and line 42 calls it. Currently however the only argument being passed is the event.

This breaks any CustomResourceProvider handlers that rely on properties or methods from the context object that is normally an argument for Lambda handlers.

Reproduction Steps

1. Write a CustomResourceProvider with Lambda code referencing context (e.g. context.getRemainingTimeInMillis()).
2. Write a resource using that CustomResourceProvider.
3. Deploy your CDK stack.
4. The Lambda will error with a TypeError: Cannot read property 'getRemainingTimeInMillis' of undefined and the stack will rollback.

What did you expect to happen?

I expected my stack to deploy successfully as it did with CDKv1.

What actually happened?

Custom resource Lambda threw TypeError: Cannot read property 'getRemainingTimeInMillis' of undefined and stack rollback or fails to deploy.

CDK CLI Version

2.1.0

Framework Version

No response

Node.js Version

16.13.1

OS

Windows 10

Language

Typescript

Language Version

4.5.4

Other information

This restricts other packages from migrating to CDKv2, such as https://github.com/udondan/aws-cloudformation-custom-resource.