fastify-server-session

A Fastify plugin to maintain state on the server

Usage no npm install needed!

<script type="module">
  import fastifyServerSession from 'https://cdn.skypack.dev/fastify-server-session';
</script>

README

fastify-server-session

This is a plugin for Fastify that facilitates keep state for clients between requests via server-side storage.

Requirements:

Installation:

npm install fastify-server-session fastify-cookie fastify-caching

Example

Server Side Storage

Using this implementation the sessions will be stored in memory on the Fastify instance making the server stateful. This is not recommended for production. It will not share state among multiple instances of the same application.

const fastify = require('fastify')()
fastify
  .register(require('fastify-cookie'))
  .register(require('fastify-caching'))
  .register(require('fastify-server-session'), {
    secretKey: 'some-secret-password-at-least-32-characters-long',
    sessionMaxAge: 900000, // 15 minutes in milliseconds
    cookie: {
      domain: '.example.com',
      path: '/'
    }
  })

fastify.get('/one', (req, reply) => {
  req.session.foo = 'foo'
  reply.send()
})

fastify.get('/two', (req, reply) => {
  reply.send({foo: req.session.foo})
})

Remote Cache Store

fastify-caching offers the connectivity to a remote store as shown below with ioredis and abstract-cache. See fastify-caching documentation for other storage capabilities.

// This example requires the following packages to be installed
// - ioredis
// - abstract-cache

const IORedis = require('ioredis')
const redis = new IORedis({host: '127.0.0.1'})
const abcache = require('abstract-cache')({
  useAwait: true,
  driver: {
    name: 'abstract-cache-redis',
    options: {client: redis}
  }
})
const fastify = require('fastify')()
fastify
  .register(require('fastify-cookie'))
  .register(require('fastify-caching'), {cache: abcache})
  .register(require('fastify-server-session'), {
    secretKey: 'some-secret-password-at-least-32-characters-long',
    sessionMaxAge: 900000, // 15 minutes in milliseconds
    cookie: {
      domain: '.example.com',
      path: '/'
    }
  })

fastify.get('/one', (req, reply) => {
  req.session.foo = 'foo'
  reply.send()
})

fastify.get('/two', (req, reply) => {
  reply.send({foo: req.session.foo})
})

Note: In the previous example the sessionMaxAge value will set the Redis TTL of the session key.

Options

The plugin accepts an options object with the following properties:

  • secretKey (Default: undefined): this is a required property that must be a string with a minimum of 32 characters.
  • sessionCookieName (Default: sessionid): a string to name the cookie sent to the client to track the session.
  • sessionMaxAge (Default: 1800000): a duration in milliseconds for which the sessions will be valid.
  • cookie: an options as described in the cookie module's documentation. The default value is:
    • domain: undefined
    • expires: same as sessionMaxAge
    • httpOnly: true
    • path: undefined
    • sameSite: true

TypeScript

To use type checking on session object you can use the declaration:

declare module 'fastify' {
  interface FastifyRequest {
    session: {
      foo: string;
      bar: number;
    };
  }
}

License

MIT License