gofrendiasgard / balasan-kelinci

rabbitmq, koa

Balasan sang Kelinci

Proof of concept, using Koa as API Gateway that encapsulate pub/sub messaging system using RabbitMQ

Why

I want to have microservices which is literally decoupled from each others. Thus, the API Gateway doesn't have to know the location of other services. All communication are handled by the messaging system.

However, this introduce a new problem as most clients are already built to handle request/reply protocol.

The Approach

I make 2 services. resepsionis, that act as API Gateway, and koki that act as internal service.

Whenever the resepsionis got any http request from client, it will publish a message Es teh dua to pesanMakanan queue.

koki listen to pesanMakanan queue and publish the reply (i.e: Es teh dua maPuluhRebu which is literally goban) to pesananDiterima queue.

Still in the same request handler, resepsionis listen to the pesananDiterima queue and yield the message as http response.

Thus, koki and resepsionis doesn't have to know each other. Furthermore, the client doesn't have to implement pub/sub mechanism by itself (i.e: the old-school AJAX Jquery will serve well).

Try it

• Invoke npm install
• Create pesanMakanan and pesananDiterima queue in your rabbitMq. (I use this connection string: amqp://root:toor@localhost:5672, but feel free to change it).
• Run koki by invoking node koki.js
• Run resepsionis by invoking resepsionis.js
• Open browser/postman, send any http request to http://localhost:3000, and you will get Es teh dua maPuluhRebu which is literally goban