lambda.ts

import type { APIGatewayProxyEventV2, APIGatewayProxyResultV2, Context } from 'aws-lambda'

// AWS Lambda Function Urls are reusing types from APIGateway
// but many fields are not used or filled with default values
// see: https://docs.aws.amazon.com/lambda/latest/dg/urls-invocation.html
// It would be nice to have types with only the used fields and add them to:
// https://github.com/DefinitelyTyped/DefinitelyTyped/tree/master/types/aws-lambda
type LambdaFunctionUrlEvent = APIGatewayProxyEventV2
type LambdaFunctionUrlResult = APIGatewayProxyResultV2

// Note: think of enhancing logging with structure (JSON) and metrics
// - @atombrenner/log-json: https://github.com/atombrenner/npm-log-json
// - pino: https://github.com/pinojs/pino
// - https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch_Embedded_Metric_Format.html
// - @aws-lambda-powertools/metrics: https://docs.powertools.aws.dev/lambda/typescript/latest/core/metrics/#getting-started

export async function handler(
  event: LambdaFunctionUrlEvent,
  context: Context,
): Promise<LambdaFunctionUrlResult> {
  console.log(context.functionName)
  console.log(`${event.requestContext.http.method} ${event.rawPath}`)
  return {
    statusCode: 200,
    headers: { 'content-type': 'application/json' },
    body: JSON.stringify(event, null, 2),
  }
}