Fastify Plugin for Google Pubsub

A plugin for Fastify to use the Google Cloud Pub/Sub Client for publishing and subscribing to topics.

Install

npm install fastify-google-pubsub

Basic Usage

After registering the plugin, publish() and subscribe() functions are added to a pubsub decorator on the fastify object. The options object on the register call needs to include all topics used by subsequent calls to publish() or subscribe(), or those calls with throw an error.

Single Topic Example

const pubsubClient = require('fastify-google-pubsub')

module.exports = async function(fastify, opts) {
  // Register the client as a plugin
  fastify.register(pubsubClient, { topics: 'topic-name']})

  // Subscribe to the topic
  const messageHandler = (message) => {
    console.log('Received Message: ', message.data.toString())
  }
  const optionalCloseHandler = () => {
    console.log('Subscription closed')
  }
  await fastify.pubsub.subscribe('topic-name', 'topic-subscription-name', messageHandler, optionalCloseHandler)

  // Publish to the same topic
  await fastify.pubsub.publish('topic-name', JSON.stringify({ message: 'contents' }), { attribute: 'value' })
}

Dual Topic Example

const pubsubClient = require('fastify-google-pubsub')

module.exports = async function(fastify, opts) {
  // Register the client as a plugin
  fastify.register(pubsubClient, { topics: ['topic-1-name', 'topic-2-name']})

  // Subscribe to the first topic
  const messageHandler = (message) => {
    console.log('Received Message: ', message.data.toString())
  }
  await fastify.pubsub.subscribe('topic-1-name', 'topic-1-subscription-name', messageHandler)

  // Publish to the second topic
  await fastify.pubsub.publish('topic-2-name', JSON.stringify({ message: 'contents' }), { attribute: 'value' })
}