What is the AWS way to add stage with @aws-cdk/aws-apigatewayv2 and @aws-cdk/aws-lambda-nodejs

[Albert-Gao]

Googled so hard, finally figured out a way, want to verify if this is the idiomatic AWS way,

basically, I want to do something like: for an API Gateway route "/hello", connect it with lambda handler hello, and deploy dev/stage/prod version according to the environment variable, and the dev/stage version of hello could be different (if I changed the handler implementation before deploying), basically, just like what serverless framework does.

import * as core from "@aws-cdk/core";
import * as apigatewayv2 from "@aws-cdk/aws-apigatewayv2";
import * as lambdaNode from "@aws-cdk/aws-lambda-nodejs";
import * as lambda from "@aws-cdk/aws-lambda";
import * as logs from "@aws-cdk/aws-logs";
import { LambdaProxyIntegration } from "@aws-cdk/aws-apigatewayv2-integrations";
import * as core from "@aws-cdk/core";

export class Lambda extends core.Construct{
  constructor(
    scope: core.Construct,
    id: string
  ) {
    super(scope, id, props);

    const stage = process.env.STAGE

    // create Http API with stage
    const api = new apigatewayv2.HttpApi(
      this,
      `Api${stage}`,
      {
        createDefaultStage: false,
      }
    );

    api.addStage("greening-stage", {
      stageName: stage,
      autoDeploy: true,
    });

    // create lambda with stage
    const handler = new lambdaNode.NodejsFunction(
      this,
      `hello${stage}`,
      {
        functionName: `hello${stage}`,
        entry: "lambda/hello.ts",
        handler: "handler",
        runtime: lambda.Runtime.NODEJS_14_X,
      }
    );

    // link API and lambda together
    api.addRoutes({
      path: "/hello",
      methods: [apigatewayv2.HttpMethod.GET],
      integration: new LambdaProxyIntegration({
           handler,
      }),
    });
  }
}

when deploy,

• for dev: STAGE=dev cdk synthesize then STAGE=dev cdk deploy
• for stage: STAGE=stage cdk synthesize then STAGE=stage cdk deploy

It created 2 versions of API gateway linked to 2 versions of lambda, all works fine

is this the suggested way? I found a handler.currentVersion.addVersion() method, but seems it needs to assign to a handler with different id, but if the id is different, this is a new resource, why should I bother use this addVersion in the 1st place? So, a bit confused here

this is simplified code, in my app, I pass the process.env.STAGE from the props parameter, and use this flow, even though it works, I found a problem with this approach, so, when I run cdk stack, App-stage will not show up, but App-dev, maybe because I set the stage default to dev.

this problem cause me wonder: am I doing it right? What am I missing here.