Building Microservices Protocols and Autonomous Systems using Muon

Currently, this is source code oriented. For a real system, it would be expected to split these into their own repositories and work in a more artifact oriented way.

Start up

Pre-requisites

You need the following installed and working :-

Java, 8+
Node/ NPM, recommend 6.8
Docker
Docker Compose
Make

It is recommended to install the Muon cli, which is an npm module

npm install -g muon-cli

Startup

This runs up the entire system. It uses docker-compose for orchestrating the processes.

make

You can use docker-compose directly to stop different services to enable local development.

Eg, to perform ui dev, you would run make and then run

docker-compose stop ui

Then, you can start the ui service in your IDE, running against the rabbit server that the environment runs up and has against the local environment.

Data Flows

There are two primary event data flows. Product Creation and Basket maintenance

Product data is added via the event (this is the standard Muon event schema)

{
	"event-type": "ProductAdded",
	"schema": "http://www.simplicityitself.io/mucon/product/1",
	"stream-name": "products",
	"service-id": "creating-service",
	"payload": {
		"product-name": "First Data",
		"product-id": "123456789",
		"description": "Hello World"
	}
}

You can add a product using the muon cli

muon event '{ "event-type": "ProductAdded", "schema": "http://www.simplicityitself.io/mucon/product/1","stream-name": "products","service-id": "creating-service","payload": {"product-name": "First Data","product-id": "123456789","description": "Hello World"}}'

Baskets are updated with the following event

{
	"event-type": "BasketProductModified",
	"schema": "http://www.simplicityitself.io/mucon/basket/1",
	"stream-name": "basket",
	"service-id": "creating-service",
	"payload": {
		"user-id": "123",
		"product-id": "123456789",
		"quantity-added": 3
	}
}

You can add an item to a users basket, by emitting the event

muon event '{"event-type": "BasketProductModified","schema": "http://www.simplicityitself.io/mucon/basket/1","stream-name": "basket","service-id": "creating-service","payload": {"user-id": "123", "product-id": "123456789","quantity-added": 3}}'

The quantity-added field is expected to also be negative.

You can add these

Services

This consists of a few services, implementing the very basics of an online shop, with supporting infrastructure services.

Support

Running are :-

RabbitMQ - for communication and discovery
Photon - For event persistence
Molecule - a management web UI

To interact with the running services, you can use the Muon CLI

> export MUON_URL=amqp://muon:microservices@localhost (1)
> muon discover      (2)


> muon introspect product-page   (3)
> muon event            (4)

Set the discovery location to tbe the AMQP server running here
Execute a discovery, see what’s running locally. (also muon disco, muon d etc)
Introspect the service product-page. See what capabilities it has
Emit an event. This is persisted into the local event store, Photon.

Application Services

The actual application is made up of several cooperating services, fronted by a very simple Muon.js + React user interface.

Product Search

Reads all product creation events, pushes them into an internal elastic search instance and presents a search interface on top of them using rpc.

muon rpc rpc://product-search/search '{"text":"blue"}'

This services also has a basic 'continuous search' facility, using the reactive stream protocol

muon stream stream://product-search/search '{"text":"blue"}'

You will receive an update whenever a new product event is read in (your search may not actually change).

Product Page microservice

A service that is able to run fully autonomously to render the product page in the shop. Contains full product specs, cross sell and active basket size counts.

UI

A simple React JS UI using Muon.js imported as a minified JS file

Muon.js can also be used when imported as a NPM module and run through webpack or browserify

muoncore/muon-intro