Demostrate how to use the popular Node web framework Express.js to deploy a Serverless REST API. This means you can use your existing code + the vast Express.js ecosystem and benefits of Serverless.

We'll install the serverless-http framework

$ npm install --save express serverless-http

The serverless-http package is a handy piece of middleware that handles the interface between your Node.js application and the specifics of API Gateway.

Let's create an index.js file that has our application code:

// index.js const serverless = require('serverless-http'); const express = require('express') const app = express() app.get('/', function (req, res) { res.send('Hello World!') }) module.exports.handler = serverless(app);

To get this application deployed, let's create a serverless.yml in our working directory:

# serverless.yml functions: app: handler: index.handler events: - http: ANY / - http: 'ANY {proxy+}'

This is a pretty basic configuration. We've created one function, app, which uses the exported handler from our index.js file. Finally, it's configured with some HTTP triggers.

We've used a very broad path matching so that all requests on this domain are routed to this function. All of the HTTP routing logic will be done inside the Express application.