NexusCS

Fastify

JavaScript libraries
Fastify lets you create HTTP servers in Node.js with good performance. This guide targets fastify v0.28.x.

Getting started

Introduction

Fastify lets you create HTTP servers in Node.js with good performance. This guide targets fastify v0.28.x.

Hello world

const fastify = require('fastify')()

fastify.get('/', (req, reply) => {
  reply.send({ hello: 'world' })
})

fastify.listen(3000, err => {
  if (err) throw err
  const port = fastify.server.address().port
  console.log(`server listening on ${port}`)
})

Plugins

app.js

fastify.register(require('./route'))

route.js

function (fastify, opts, next) {
  fastify.get('/', (req, reply) => {
    reply.send({ hello: 'world' })
  })

  next()
})

Compose your app functionality into plugins. Plugins are simply functions.

See: Plugins

Routes

Writing routes

fastify.route({
  method: 'GET',
  url: '/',
  schema: { ··· },
  handler: (req, reply) => { ··· }
  beforeHandler: (req, reply, done) => { ··· }
})

Shorthand declarations

fastify.get(path, [options], handler)
fastify.head(···)
fastify.post(···)
fastify.put(···)
fastify.delete(···)
fastify.options(···)
fastify.patch(···)

Async/await

fastify.get('/', options, async (req, reply) => {
  return data
  // or
  reply.send(data)
})

When using async functions, you can either return data or use reply.send.

Request/reply

Request

request.query
request.body
request.params
request.headers
request.req  // Node.js core
request.log.info('hello')

See: Request

Reply

Response headers

reply.code(404)
reply.header('Content-Type', 'text/html')
reply.type('text/html')

Redirects

reply.redirect('/foo')
reply.redirect(302, '/foo')

Sending

reply.send(payload)
reply.sent // → true|false

See: Reply

JSON schema

Define a JSON schema

const schema = {
  querystring: {
    name: { type: 'string' },
    excitement: { type: 'integer' }
  },
  response: {
    200: {
      type: 'object',
      properties: {
        hello: { type: 'string' }
      }
    }
  }
}

Pass it to the route

fastify.get('/', { schema }, (req, reply) => {
  ···
})

or (same as above)

fastify.route({
  method: 'GET',
  url: '/',
  schema,
  handler: (req, reply) => { ··· }
})

By defining a JSON schema, you get validation and improved performance.

See: Validation and serialization

Plugins

With function

fastify.register(
  require('./route'),
  err => { if (err) throw err }
)

route.js

module.exports = (fastify, options, next) => {
  fastify.get('/', ···)
  next()
}

See: Register

Multiple

fastify.register([
  require('./another-route'),
  require('./yet-another-route')
], opts, (err) => {
  if (err) throw err
})

You can pass arrays to register().

Register with prefix

fastify.register(
  require('./route'),
  { prefix: '/v1' }
)

This prefixes all routes in that module.

Helmet

const helmet = require('fastify-helmet')

fastify.register(helmet)

See: fastify-helmet

fastify-plugin

const fp = require('fastify-plugin')

module.exports = fp((fastify, opts, next) => {
  // your plugin code
  fastify.decorate('utility', () => {})

  next()
}, '0.x')

Allows you to limit Fastify versions via semver, and allows you not make a new Fastify scope.

See: fastify-plugin

Decorators

Middleware

Middleware

fastify.use(require('cors')())
fastify.use(require('dns-prefetch-control')())
fastify.use(require('frameguard')())
fastify.use(require('hide-powered-by')())
fastify.use(require('hsts')())
fastify.use(require('ienoopen')())
fastify.use(require('x-xss-protection')())

Compatible with Express and Restify middlewares. (Don't use these middleware, these are covered by fastify-helmet.)

See: Middlewares

Template rendering

point-of-view

const fastify = require('fastify')()

fastify.register(require('point-of-view'), {
  engine: {
    ejs: require('ejs')
  }
})

fastify.get('/', (req, reply) => {
  reply.view('/templates/index.ejs', { text: 'text' })
})

Support ejs, pug, handlebars and marko.

See: point-of-view

Options

fastify.register(require('point-of-view'), {
  engine: {
    ejs: require('ejs')
  },
  templates: '/templates',
  options: {}
})

templates lets you update the templates folder. options are options passed onto the template engines.