Moleculer

Moleculer is a fast, modern and powerful microservices framework for Node.js. It helps you to build efficient, reliable & scalable services. Moleculer provides many features for building and managing your microservices.

Website: https://moleculer.services

Documentation: https://moleculer.services/docs

What's included

Promise-based solution (async/await compatible)
request-reply concept
support event driven architecture with balancing
built-in service registry & dynamic service discovery
load balanced requests & events (round-robin, random, cpu-usage, latency, sharding)
many fault tolerance features (Circuit Breaker, Bulkhead, Retry, Timeout, Fallback)
plugin/middleware system
support versioned services
support Streams
service mixins
built-in caching solution (Memory, MemoryLRU, Redis)
pluggable loggers (Console, File, Pino, Bunyan, Winston, Debug, Datadog, Log4js)
pluggable transporters (TCP, NATS, MQTT, Redis, NATS Streaming, Kafka, AMQP 0.9, AMQP 1.0)
pluggable serializers (JSON, Avro, MsgPack, Protocol Buffer, Thrift)
pluggable parameter validator
multiple services on a node/server
master-less architecture, all nodes are equal
parameter validation with fastest-validator
built-in metrics feature with reporters (Console, CSV, Datadog, Event, Prometheus, StatsD)
built-in tracing feature with exporters (Console, Datadog, Event, Jaeger, Zipkin)
official API gateway, Database access and many other modules...

Installation

$ npm i moleculer --save

$ yarn add moleculer

Create your first microservice

This example shows you how to create a small service with an add action which can add two numbers and how to call it.

const { ServiceBroker } = require("moleculer");

// Create a broker
const broker = new ServiceBroker();

// Create a service
broker.createService({
    name: "math",
    actions: {
        add(ctx) {
            return Number(ctx.params.a) + Number(ctx.params.b);
        }
    }
});

// Start broker
broker.start()
    // Call service
    .then(() => broker.call("math.add", { a: 5, b: 3 }))
    .then(res => console.log("5 + 3 =", res))
    .catch(err => console.error(`Error occurred! ${err.message}`));

Try it in your browser

Create a Moleculer project

Use the Moleculer CLI tool to create a new Moleculer based microservices project.

Create a new project (named moleculer-demo)

$ npx moleculer init project moleculer-demo

Open project folder
```
$ cd moleculer-demo
```
Start project
```
$ npm run dev
```
Open the http://localhost:3000/ link in your browser. It shows a welcome page which contains many information about your project & you can test the generated services.

🎉 Congratulations! Your first Moleculer-based microservices project is created. Read our documentation to learn more about Moleculer.

Official modules

We have many official modules for Moleculer. Check our list!

Supporting

Moleculer is an open source project. It is free to use for your personal or commercial projects. However, developing it takes up all our free time to make it better and better on a daily basis. If you like Moleculer framework, please support it.

Thank you very much!

For enterprise

Available as part of the Tidelift Subscription.

The maintainers of moleculer and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source dependencies you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use. Learn more.