imicros-transporter

Two way transporter for Moleculer services

• actions/responses and registry messages non-persistent via NATS
• events persistent via kafka

Installation

$ npm install imicros-transporter --save

Requires installation of the additional modules nats and kafkajs

Usage

const { KafkaNats } = require("imicros-transporter");

const transporterSettings = {
    kafka: {
        brokers: ["192.168.2.124:9092"]
        /* optional: additional settings
        ssl: null,                           // refer to kafkajs documentation
        sasl: null,                          // refer to kafkajs documentation
        retry: {
             initialRetryTime: 100,          // default 100
             retries: 8                      // default 8
        }
        */
    },
    nats: {
        url: "nats://192.168.2.124:4222"
        /* optional: additional settings
        user: "admin",
        pass: "1234"
        */
    }
};
kafka = new ServiceBroker({ nodeID: uuid(), transporter: new KafkaNats(transporterSettings), disableBalancer: true });

Force emittung events always

If no running service has subscribed an event, it will not be emitted in the current moleculer version.

To force to emit always - also if no one is listening, we must add a small middleware:

const { KafkaNats } = require("imicros-transporter");
const { EventsMiddleware } = require("imicros-transporter");

kafka = new ServiceBroker({ nodeID: uuid(), transporter: new KafkaNats(transporterSettings), disableBalancer: true, middlewares: [EventsMiddleware] });