restyped-api-gateway-lambda-proxy-async

RESTyped API Gateway Lambda Proxy Wrapper

API Gateway Lambda Proxy route wrappers for declaring type-safe APIs with RESTyped. Also supports async route functions.

WIP

Probably not ready to use yet.

Usage

npm install restyped-api-gateway-lambda-proxy-async

It's just like normal express, except you'll need to provide a RESTyped API definition file for the API you want to use, and return a Promise with your response value in order to activate type-checking.

import { APIGatewayEvent, APIGatewayEventRequestContext, ProxyCallback } from '@types/aws-lambda'
import RestypedRouter from 'restyped-api-gateway-lambda-proxy-async'
import {MyAPI} from './MyAPI' // <- Your API's RESTyped definition

// Lambda function body.
export function(
  event: APIGatewayEvent,
  context: APIGatewayEventRequestContext,
  callback: ProxyCallback) {

const router = RestypedRouter<MyAPI>(event, context, callback);

// You'll get a compile error if you declare a route that doesn't exist in your API definition.
router.post('/posts', async (req, res) => {
  // Error if you try to access body properties that don't exist in your API definition.
  const {title, author, body} = req.body
  //     ^ string  ^ string  ^ number

  const postId = await Post.create(title, author, body)

  // Error if you don't return the response type defined in your API definition.
  return res({
    body: postId
  });

}

Error handling and status codes

Error handling

You can throw from inside your async function and your thrown error will be passed to next(err).

Status codes

Use express directly to send responses with status codes. Don't forget to return after you res.send().

router.get('/posts/{id}', async (req, res) => {
  const {id} = req.params
  const post = await Post.get(id)

  if (!post) {
    return res({
      statusCode: 404
    })
  }

  return res({
    body: Post
  })
})