pablitovicente / nats-cluster

Simple NATS Cluster

Quick demo on how to use NATS Streams with NodeJS

Prerequisites

• Docker
• NodeJS 16+

Setup

• docker-compose up and wait for Nats to start
• cd setup && ./build_and_run.sh to create the stream (in a real world scenario this is done by the application)
• npm i -g pm2 (if you want to stress test)

How to run?

• start multiple producers to fill the stream pm2 start producer/producer.mjs && pm2 scale producer 10 (each producer publishes 20000 messages with delivery ack)
  • this will start 10 producers and keep running forever
  • you can stop the producers with pm2 stop producer
• start a worker (or multiple on different terminals) node worker/worker.mjs
• you can also start workers with pm2 pm2 start workers/worker.mjs && pm2 scale worker 5 && pm2 logs

You can also look at debug output by running NATS toolbox container

• docker run --network docker-compose-nats_nats --rm -it natsio/nats-box:latest
• then nats sub debug --server nats-1

Architecture

TODO

• refactor the NodeJS code to be a bit less hacky
• provide a more complex stream and consumer structure
• dockerize everything