(aws-lambda-nodejs): NodejsFunction support EdgeFunction for Lambda@Edge

If I wish to use NodejsFunction to create a Lambda@Edge, I need to make sure that my whole stack is currently in us-east.

If there was a prop or flag on NodejsFunction props, we could easily deploy our NodeJS functions to Lambda@Edge.

Something similar likely needs to happen with other lambda helpers.

It seems someone has already made a EdgeFunction construct: https://github.com/aws/aws-cdk/pull/10500

So it could be a case of just refactoring so that there was a class that inherited from that instead of lambda.Function.

This would probably need to be done with the go/python helpers, too.

Use Case

I would like to use NodejsFunction to create lambdas that can be used with Lambda@Edge with my stack in any region.

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

---

This is a 🚀 Feature Request

[Shiroy]

I think a better implementation would be to publicly expose the bundler in aws-lambda-nodejs as a top-level component instead of keeping it package private.

https://github.com/aws/aws-cdk/blob/464cdc0baa1fc5b0634e428a9c7a15de4ca93d50/packages/%40aws-cdk/aws-lambda-nodejs/lib/bundling.ts#L40

This would allow any kind of lambda function to rely on the esbuild bundler. This would benefit

https://github.com/aws/aws-cdk/blob/464cdc0baa1fc5b0634e428a9c7a15de4ca93d50/packages/%40aws-cdk/aws-cloudfront/lib/experimental/edge-function.ts#L37

and

https://github.com/aws/aws-cdk/blob/464cdc0baa1fc5b0634e428a9c7a15de4ca93d50/packages/%40aws-cdk/aws-cloudfront/lib/function.ts#L133

As an example, the following snippet works for deploying Lambda@Edges but it relies on the Bundling component which is internal to aws-lambda-nodejs

import { Runtime } from "@aws-cdk/aws-lambda";
import * as cdk from "@aws-cdk/core";
import { Bundling } from "@aws-cdk/aws-lambda-nodejs/lib/bundling"; 
// Not OK as we rely on the package private bundler. 
// This does not provide any stability guarantee in the long run.
import * as path from "path";
import { EdgeFunction } from "@aws-cdk/aws-cloudfront/lib/experimental";

export interface PrefixRemoverProps {
    prefixToRemove: string
}

export class PrefixRemover extends cdk.Construct {
    readonly lambda: EdgeFunction
    constructor(scope: cdk.Construct, name: string, props: PrefixRemoverProps) {
        super(scope, name)

        this.lambda = new EdgeFunction(this, `${name}-prefixRemover` , {
            code: Bundling.bundle({
                runtime: Runtime.NODEJS_14_X,
                depsLockFilePath: path.join(__dirname, "src" , "package-lock.json"),
                entry: path.join(__dirname, "src", "handler.ts"),
                projectRoot: path.join(__dirname, "src"),
                define: {
                    'process.env.PREFIX_TO_REMOVE': `"${props.prefixToRemove}"`
                },
                forceDockerBundling: true
            }),
            runtime: Runtime.NODEJS_14_X,
            handler: "index.handler"
        });
    } 
}

[hugomallet]

Cannot import Bundling with CDK v2 :

Error [ERR_PACKAGE_PATH_NOT_EXPORTED]: Package subpath './aws-lambda-nodejs/lib/bundling.js' is not defined by "exports"