README

fastify-redis

Fastify Redis connection plugin; with this you can share the same Redis connection in every part of your server.

Under the hood ioredis is used as client, the options that you pass to register will be passed to the Redis client.

Install

npm i fastify-redis --save

Usage

Add it to your project with register and you are done! You can access the Redis client via fastify.redis. The client is automatically closed when the fastify instance is closed.

'use strict'

const fastify = require('fastify')()

fastify.register(require('fastify-redis'), { host: '127.0.0.1' })
// or
fastify.register(require('fastify-redis'), { url: 'redis://127.0.0.1', /* other redis options */ })

fastify.get('/foo', (req, reply) => {
  const { redis } = fastify
  redis.get(req.query.key, (err, val) => {
    reply.send(err || val)
  })
})

fastify.post('/foo', (req, reply) => {
  const { redis } = fastify
  redis.set(req.body.key, req.body.value, (err) => {
    reply.send(err || { status: 'ok' })
  })
})

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

You may also supply an existing Redis client instance by passing an options object with the client property set to the instance. In this case, the client is not automatically closed when the Fastify instance is closed.

'use strict'

const fastify = require('fastify')()
const redis = require('redis').createClient({ host: 'localhost', port: 6379 })

fastify.register(require('fastify-redis'), { client: redis })

Note: by default, fastify-redis will not automatically close the client connection when the Fastify server shuts down. To opt-in to this behavior, register the client like so:

fastify.register(require('fastify-redis'), {
  client: redis,
  closeClient: true
})

Registering multiple Redis client instances

By using the namespace option you can register multiple Redis client instances.

'use strict'

const fastify = require('fastify')()
const redis = require('redis').createClient({ host: 'localhost', port: 6379 })

fastify
  .register(require('fastify-redis'), {
    host: '127.0.0.1',
    port: 6380,
    namespace: 'hello'
  })
  .register(require('fastify-redis'), {
    client: redis,
    namespace: 'world'
  })

// Here we will use the `hello` named instance
fastify.get('/hello', (req, reply) => {
  const { redis } = fastify

  redis.hello.get(req.query.key, (err, val) => {
    reply.send(err || val)
  })
})

fastify.post('/hello', (req, reply) => {
  const { redis } = fastify

  redis['hello'].set(req.body.key, req.body.value, (err) => {
    reply.send(err || { status: 'ok' })
  })
})

// Here we will use the `world` named instance
fastify.get('/world', (req, reply) => {
  const { redis } = fastify

  redis['world'].get(req.query.key, (err, val) => {
    reply.send(err || val)
  })
})

fastify.post('/world', (req, reply) => {
  const { redis } = fastify

  redis.world.set(req.body.key, req.body.value, (err) => {
    reply.send(err || { status: 'ok' })
  })
})

fastify.listen(3000, function (err) {
  if (err) {
    fastify.log.error(err)
    process.exit(1)
  }
})

Redis streams (Redis 5.0 or greater is required)

fastify-redis supports Redis streams out of the box.

'use strict'

const fastify = require('fastify')()

fastify.register(require('fastify-redis'), {
  host: '127.0.0.1',
  port: 6380
})

fastify.get('/streams', async (request, reply) => {
  // We write an event to the stream 'my awesome fastify stream name', setting 'key' to 'value'
  await fastify.redis.xadd(['my awesome fastify stream name', '*', 'hello', 'fastify is awesome'])

  // We read events from the beginning of the stream called 'my awesome fastify stream name'
  let redisStream = await fastify.redis.xread(['STREAMS', 'my awesome fastify stream name', 0])

  // We parse the results
  let response = []
  let events = redisStream[0][1]

  for (let i = 0; i < events.length; i++) {
    const e = events[i]
    response.push(`#LOG: id is ${e[0].toString()}`)

    // We log each key
    for (const key in e[1]) {
      response.push(e[1][key].toString())
    }
  }

  reply.status(200)
  return { output: response }
  // Will return something like this :
  // { "output": ["#LOG: id is 1559985742035-0", "hello", "fastify is awesome"] }
})

fastify.listen(3000, function (err) {
  if (err) {
    fastify.log.error(err)
    process.exit(1)
  }
})

NB you can find more information about Redis streams and the relevant commands here and here.

Redis connection error

Majority of errors are silent due to the ioredis silent error handling but during the plugin registration it will check that the connection with the redis instance is correctly estabilished. In this case you can receive an ERR_AVVIO_PLUGIN_TIMEOUT error if the connection can't be estabilished in the expected time frame or a dedicated error for an invalid connection.

Acknowledgements

This project is kindly sponsored by:

License

Licensed under MIT.

Usage no npm install needed!