LambdalithとSingle purpose Lambdaは1つのAPI Gatewayで共存できる

import {
  aws_apigateway,
  aws_lambda,
  aws_lambda_nodejs,
  aws_logs,
  RemovalPolicy,
  Stack,
  StackProps,
} from 'aws-cdk-lib';
import { Construct } from 'constructs';

export class LambdalithAndSinglePurposeLambdaStack extends Stack {
  constructor(scope: Construct, id: string, props?: StackProps) {
    super(scope, id, props);

    const monolithLambda = new aws_lambda_nodejs.NodejsFunction(
      this,
      'MonolithLambda',
      {
        architecture: aws_lambda.Architecture.ARM_64,
        entry: 'src/lambdalith/entry-point.ts',
        runtime: aws_lambda.Runtime.NODEJS_20_X,
        bundling: {
          forceDockerBundling: false,
        },
      },
    );

    const singlePurposeLambda = new aws_lambda_nodejs.NodejsFunction(
      this,
      'SinglePurposeLambda',
      {
        architecture: aws_lambda.Architecture.ARM_64,
        entry: 'src/single-purpose-lambda/dog.ts',
        runtime: aws_lambda.Runtime.NODEJS_20_X,
        bundling: {
          forceDockerBundling: false,
        },
      },
    );

    /**
     * REST API を作成
     */
    const logGroup = new aws_logs.LogGroup(
      this,
      'MonolithSinglePurposeTogetherAccessLogs',
    );
    const restApi = new aws_apigateway.RestApi(
      this,
      'MonolithSinglePurposeTogether',
      {
        defaultIntegration: new aws_apigateway.LambdaIntegration(
          monolithLambda,
        ), // Lambdalithの設定
        defaultCorsPreflightOptions: {
          allowOrigins: aws_apigateway.Cors.ALL_ORIGINS,
          allowMethods: aws_apigateway.Cors.ALL_METHODS,
          allowHeaders: aws_apigateway.Cors.DEFAULT_HEADERS,
        },
        cloudWatchRole: true,
        cloudWatchRoleRemovalPolicy: RemovalPolicy.DESTROY,
        deployOptions: {
          accessLogDestination: new aws_apigateway.LogGroupLogDestination(
            logGroup,
          ),
          accessLogFormat: aws_apigateway.AccessLogFormat.clf(),
        },
      },
    );
    restApi.root.addProxy(); // Lambdalithの設定
    restApi.root
      .addResource('animals')
      .addResource('dog')
      .addMethod(
        'GET',
        new aws_apigateway.LambdaIntegration(singlePurposeLambda, {
          proxy: true,
        }),
      ); // Single purpose Lambdaの設定
  }
}

import { injectLambdaContext, Logger } from "@aws-lambda-powertools/logger";
import serverlessExpress from "@codegenie/serverless-express";
import middy from "@middy/core";
import cors from "cors";
import express, { Request, Response } from "express";

const app = express();
app.use(cors());
app.use(express.json());
const logger = new Logger();

app.get(
  "/animals/cat",
  async (req: Request, res: Response): Promise<void> => {
    logger.info(req.path);
    const response = {
      statusCode: 200,
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ animal: "cat" }),
    }

    res.header(response.headers);
    res.status(response.statusCode).send(response.body);
  },
);

export const handler = middy(serverlessExpress({ app })).use(
  injectLambdaContext(logger),
);

import { APIGatewayProxyEvent, APIGatewayProxyResult } from 'aws-lambda';

export const handler = async (
  event: APIGatewayProxyEvent,
): Promise<APIGatewayProxyResult> => {
  console.log(event);
  return {
    statusCode: 200,
    body: JSON.stringify({ animal: 'dog' }),
  };
};

curl https://sampleid.execute-api.ap-northeast-1.amazonaws.com/prod/animals/dog
{"animal":"dog"}

curl https://sampleid.execute-api.ap-northeast-1.amazonaws.com/prod/animals/cat
{"animal":"cat"}