Roger Rabbit

Roger Rabbit is a module that makes the process of consuming and publishing messages in message brokers easier. It is a wrapper for amqplib.

Install

npm install @klicksite/roger-rabbit --save

Documentation

Broker

Broker expect to receives a rabbitMQ connection string and broker options. Example:

// broker.js
const Broker = require('roger-rabbit');

const broker = new Broker('amqp://guest:guest@localhost:5672');

module.exports = broker;

broker.init

Use broker.init to initialize broker, creating connections and channels based on broker options. Example:

// main.js
const broker = require('./broker');

(async() => {
  await broker.init();
})();

broker.assertExchanges

Use broker.assertExchanges to create or check exchanges. It expects to receive an array of exchanges (exchange options). Example:

const broker = require('./broker');

const exchanges = [
  { name: 'user_events', type: 'direct' },
  { name: 'repo_events', type: 'topic', options: { durable: true } },
  { name: 'commit_events', type: 'fanout' },
];

(async() => {
  await broker.assertExchanges(exchanges);
})();

broker.consume

broker.consume expects to receive an object with queue and array of bindings and callback. Example:

const broker = require('./broker');

const queue = {
  name: 'queue.name',
  options: {
    durable: true,
  },
};

const bindings = [
  { exchange: 'user_events', routingKey: 'user_events.routingKey' },
  { exchange: 'repo_events', routingKey: 'repo_events.routingKey' },
];

(async() => {
  await broker.consume({ queue, bindings }, (message, /* fields */) => {
    // do something
    // throw an error to reject message
  });
})();

broker.publish

broker.publish expects to receive exchange, routing key, message and publish options. Example:

const options = { persistent: true };

broker.publish({
    exchange: 'user_events',
    routingKey: 'user_events.routingKey',
    message: { message: 'message' },
    options,
  })

broker.channels

Use broker.channels to get channels. Examples:

const broker = require('./broker');
let context;
let channel;

//consumer
context = 'consumer';
channel = broker.channels[context].default;

//publisher
context = 'publisher';
channel = broker.channels[context].default; // or broker.channels[context].confirmation;

Broker options

| Option | Description | Required | Default | | ------------------------|---------------------------------------------|-----------|---------| | channelMax | number max of channels (max 3) | no | 3 | | publisher | publisher object | no | _ | | publisher.default | create publish channel without confirmation | no | true | | publisher.confirmation | create publish channel with confirmation | no | false | | consumer | consumer object | no | _ | | consumer.default | create consume channel | no | true | | prefetch | channel prefetch count | no | 1 |

Exchange options

| Option | Description | Default | | --------|-----------------------------------------------------------------------------------------------------------------|-------------------------| | type | direct, topic, fanout | empty string (deafault) | | name | exchange name | null | | options | options used in assertExchange | null |

Queue options

| Option | Description | Default | | --------|-----------------------------------------------------------------------------------------------------------|---------| | name | queue name | null | | options | options used in assertQueue | null |

Binding options

| Option | Description | Default | | -----------|------------------|---------| | exchange | exchange name | null | | routingKey | routing key name | null |