AWS Serverless Express
Run serverless applications and REST APIs using your existing Node.js application framework, on top of AWS Lambda and Amazon API Gateway. The sample provided allows you to easily build serverless web applications/services and RESTful APIs using the Express framework.
Getting Started
npm install aws-serverless-express
// lambda.js
'use strict'
const awsServerlessExpress = require('aws-serverless-express')
const app = require('./app')
const server = awsServerlessExpress.createServer(app)
exports.handler = (event, context) => { awsServerlessExpress.proxy(server, event, context) }
Package and create your Lambda function, then configure a simple proxy API using Amazon API Gateway and integrate it with your Lambda function.
Quick Start/Example
Want to get up and running quickly? Check out our basic starter example which includes:
- Lambda function
- Express server
Swagger file - Serverless Application Model (SAM)/CloudFormation template
- Helper scripts to configure, deploy, and manage your application
Getting the API Gateway event object
This package includes middleware to easily get the event object Lambda receives from API Gateway
const awsServerlessExpressMiddleware = require('aws-serverless-express/middleware')
app.use(awsServerlessExpressMiddleware.eventContext())
app.get('/', (req, res) => {
res.json(req.apiGateway.event)
})
Is AWS serverless right for my app?
Benefits
- Pay for what you use
- No infrastructure to manage
- Auto-scaling with no configuration needed
- Usage Plans
- Caching
- Authorization
- Staging
- SDK Generation
- API Monitoring
- Request Validation
- Documentation
Considerations
- For apps that may not see traffic for several minutes at a time, you could see cold starts
- Cannot use native libraries (aka Addons) unless you package your app on an EC2 machine running Amazon Linux
- Stateless only
- API Gateway has a timeout of 29 seconds, and Lambda has a maximum execution time of 15 minutes.