Allow to register multiple instances of Redis client.

[darkgl0w]

🚀 Feature Proposal

Allow to register multiple instances of Redis client.

Motivation

This feature will make it easier to use Redis features such as Pub/Sub with fastify-redis.

Example

We register 2 different clients giving each one a distinct namespace:

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

fastify
  .register(require('fastify-redis'), {
    host: '127.0.0.1',
    namespace: 'subscriber'
  })
  .register(require('fastify-redis'), {
    client: redis,
    namespace: 'publisher'
  })

// ...

Then we can do something like this in our application :

// ...
const channel = 'fastifyIsAwesome'

fastify.redis.subscriber.subscribe(channel, (error, count) => {
  if (error) {
    throw new Error(error)
  }

  console.log(`Subscribed to ${count} channel. Listening for updates on the '${channel}' channel.`)
})

fastify.redis.subscriber.on('message', (channel, message) => {
  console.log(`We received the following message from '${channel}': ${message}`)
})

fastify.redis.publisher.publish(channel, 'hello');

// We would have a console output like this :

// Subscribed to 1 channel. Listening for updates on the 'fastifyIsAwesome' channel.
// We received the following message from 'fastifyIsAwesome': hello
// We received the following message from 'fastifyIsAwesome': world