TechKids Edu Rabbit Queue

User guide

Connect

import { connect as tkQueueConnect } from 'tk-queue';
const queueUri = `amqp://${rabbitConfig.USERNAME}:${rabbitConfig.PASSWORD}@${rabbitConfig.HOST}:${rabbitConfig.PORT}`
tkQueueConnect(queueUri);

Producer

import { RbProducer } from 'tk-queue';
// Initialize
const rbUserProducer = RbProducer('user');

// Send message when connection is ready
rbUserProducer.send('upsert', <new user data>);

Consumer

// Initialize
import { RbConsumer } from 'tk-queue';

const rbUserConsumer = new RbConsumer(
  "tk-lm",
  "user",
  (data) => new Promise((resolve, reject) => {
    // Upsert user here
    resolve();
  }),
  (_id) => new Promise((resolve, reject) => {
    // Delete user here
    resolve();
  })

// Listen when connection is ready
rbUserConsumer.listen();

Note

Queue design:

• Some keywords:
  • A producer is a user application that sends messages.
  • A queue is a buffer that stores messages.
  • A consumer is a user application that receives messages.
  • An exchange is a very simple thing. On one side it receives messages from producers and the other side it pushes them to queues.
• Each service occupies one and only one queue, (e.g. tk-lm-service, tk-hr-service, tk-crm,...)
• Each resource occupies one and only one exchange, (e.g. course, user, registration,...), has only one producer and multi consumer.
• Related tutorial about how all that things work together: Read

Message format:

• type: Operation type (e.g. upsert, delete)
• data: The udpated data

If there is problem with message in queue, the team should treat it as very critical issuse, thus stop whatever they are doing to fix it

Developer guide

Develop

index.ts: The whole lib

Publish

• Change version in package.json file:

{
  "name": "tk-queue",
  "version": "x.x.x",
  ...
}

• Build npm run build

• Publish npm publish