Methodulus

motivation

• we want microservices!
• we need a dynamic system architecture!
• we want it all!

automatic server to server connectivity using a dynamic rpc transport layer

npm i -S methodulus

Hello methodulus

This example creats a rest (express based) server using a controller class Player

it is configured to run the class code locally via an http server.

import { Player } from './controllers/player';
import { ServerConfig, ClientConfig, ConfiguredServer, MethodType, ServerType } from 'methodulus';

@ServerConfig(ServerType.Express, { port: process.env.PORT || 8020 })
@ClientConfig(Player, MethodType.Local)
class SetupServer extends ConfiguredServer {

}

new SetupServer();

the Player class

import { Body, Method, MethodConfig, MethodType, Param, Query, Verbs, MethodError, MethodResult } from 'methodulus';
import { PlayerModel } from '../models/player';


@MethodConfig('Player')
export class Player {
    @Method(Verbs.Post, '/api/player')
    public async create() {
        let p = new PlayerModel('1', 'player 1');
        await DB.Player.insert(p);
        return new MethodResult(p)
    }

    @Method(Verbs.Get, '/api/player/:player_id')
    public async read( @Param('player_id') playerId: number) {
        return await DB.Player.find({ 'Id': playerId });
    }

    @Method(Verbs.Put, '/api/player')
    public async update() {

    }


    @Method(Verbs.Delete, '/api/player')
    public delete() {

    }



}

Classes & API

ConfiguredServer

this class is the base class for the server implementation. it uses the Server & Client decorators to apply the desired configuration.

@Server(ServerType, options)

syntetic suger for MethodulusConfig.run() function.

@Client(ClassType, MethodType, resolver?)

syntetic suger for MethodulusConfig.use() function.

MethodulusConfig

configuration must complete before the server starts. configure each controller class to its desired state

let config = new MethodulusConfig()

.run(ServerType, options)

the run method determines what kind of server to run on the listening part of the application. to listen to REST request you should run ServerType.Expess and to listen to redis channel use ServerType.Redis .

ServerType

• Express
• Redis
• MQ
• Socket

.use(classType, MethodType, resolver)

the use method registers the way a class should be activated. the first parameter is a class decorated with methodulus decoratos.

MethodType

avaliable options are Local | Http | MQ | Socket | Redis

• Local run the code in the class, no proxy or transport required.

• Http run the code using an http request to a microservice.

• MQ use amqp rpc to execute the class code

• Socket directly connect to a server using websocket connection.

• Redis use redis rpc to execute the class code

Resolver

in order to access the correct service methodulus uses a resolver, which may be a literal containing the service uri or a promise returning the same.

resolvers are attached to a class, allowing the application to use different resolvers for different services.

Available servers

an instamce of methodulus can run multiple listeners in different channels. the current list is:

• express
• socketio
• amqp
• redis

here is a simple local configuration: The class Player will execute locally.

let servers = ['express']; 
let config = new MethodulusConfig(servers);
let resolver = 'http://127.0.0.1:8090';
config.run(ServerType.express, {port: process.env.PORT })
config.use(TestClass, MethodType.Local,resolver);

Server

creates an agnostic configured server.

const server = new Server(process.env.PORT);

Server methods are chainable and should e called in this order

const server = await new Server(process.env.PORT).configure(config).start();

Decorators

Class decorators

@MethodConfig

decorating a class with the decorator will turn it into a methodulus end point.

@MethodulusConfig(applicationname, [middlewares]?)

@Method

Each decorated method in the MethodConfig decorated class will become a function endpoint of the methodulus application.

@Method(Verb, route, [middlewares])

Parameter decorators

a decorated method should use the following parameter decorators to indicate the source of each argument.

@Query

@Param

@Body

@Request

@Response