fastify-socket.io enables the use of Socket.io in a Fastify application.

Supports Fastify versions 3.x

npm i fastify-socket.io socket.io

Require fastify-socket.io and register it as any other plugin, it will add a io decorator.

const fastify = require('fastify')()

fastify.register(require('fastify-socket.io'), {
  // put your options here
})

fastify.get('/', (req, reply) => {
  fastify.io.emit('hello')
})

fastify.listen(3000)

For more details see examples

You can use it as is without passing any option, or you can configure it as explained by Socket.io doc.

The plugin also adds an onClose hook which closes the socket server when the fastify instance is closed.

From v4 types will no longer be included in the plugin package but will need to be installed separately:

npm i -D types-fastify-socket.io

This is necessary to allow, eventually, the developer to be able to define custom types and make use of the socket.io new types system (doc).

The code is a port for Fastify of socket.io.

Licensed under MIT.
socket.io license