@juniorcitizen/express-web-server

express web server implemented based on clean architecture

• HIGHLIGHT

• INSTALLATION

• USAGE

• PLUGINS AND EXTENSIONS

• ROUTER PLUGIN SYSTEM

• API

HIGHLIGHTS

• Express.js web server written in typescript

• based on clean architecture

• popular Express.js middlewares are available as plug-ins

• accept external middleware plug-ins and server extensions

• plug-in routing system

INSTALLATION

npm install --save @juniorcitizen/express-web-server

USAGE

import {
  StartWebServerUseCaseDriver as UseCaseDriver,
  StartWebServerServiceFactory as ServiceFactory,
  RouterPlugIn, // router plugin
  Morgan, // middleware plugins
} from '@juniorcitizen/express-web-server'

// factory for extending server functionalities
const serviceFactory = new ServiceFactory()

// add morgan logger plugin
const PROD_MODE = process.env.NODE_ENV==='production'
serviceFactory.plugIn(new Morgan({PROD_MODE: false}))

// add a router
const appRouter = new RouterPlugIn('/')
appRouter.addAllHandlers([middleware..., route handler...])

// add a second router
const testRouter = new RouterPlugIn('/test')
testRouter.addPostHandlers([middleware..., route handler...])

// attach testRouter to the appRouter
appRouter.attachChild(testRouter)

// attach appRouter to Express server
serviceFactory.plugIn(appRouter)

// instantiate server service
const startWebServer = new StartWebServer(serviceFactory)

// start server
startWebServer.execute({PORT: 3000})

PLUGINS AND EXTENSIONS

Available plugIns & extensions

• Response compression

• EJS templating engine

• Server-side session with Redis caching:

  • redis client: ioredis

  • redis store: connect-redis

• HTTP header security

• JSON request-body parser

• Request loggier

• favicon caching

• static-file serving

• trust proxy

• urlencoded request-body parser

• TO DO:

  • CSRF protection

  • Enforce ssl

  • HSTS protection

  • Rate-limit

  • Response throttling

  • XSS protection

How to roll your own plugIns & extensions

import EnvironmentVariables from '@juniorcitizen/environment-variables'
import {
  StartWebServer,
  StartWebServerServiceFactory as ServiceFactory,
  AbstractServicePlugIn, // extend the plugin base class
} from '@juniorcitizen/express-web-server'

// example of a global route-middleware plugIn
class MyPlugIn extends AbstractServicePlugIn {
  // dependencies can be injected
  // through the constructor
  constructor(thing, someFunction) {
    super()
    this.thing = thing
    this.someFunction = someFunction
    this._middlware = (req, res, next) => {
      this.someFunction()
      console.log(this.thing)
      next()
    }
  }
  // expose the '_middleware' private member
  // useful if this middleware is used on particular routes (non-global)
  // ***implementation of this getter is required if writing typescript***
  // ***for global middlewares, just return undefined***
  getter middleware() {
    return this._middleware
  }
  // an instance of the Express app is exposed
  // to the 'execute' method, enable middleware
  // and extension to the Express server
  // ***implementation of this method is required***
  execute(app) {
    app.use(this._middleware)
  }
}

const serviceFactory = new ServiceFactory() // service factory
// make your plug-in dependencies
const someFunction = () => {
  console.log('someFunction is executed')
}
const thing = 'I am the thing'
const myPlugIn = new MyPlugIn(thing, someFunction) // instantiate your plug-in
serviceFactory.plugIn(myPlugIn) // register your plug-in
const startWebServer = new StartWebServer(serviceFactory) // instantiate server
// setup and plug-in your routers...
// ...
// ...
startWebServer.execute({PORT: 3000}) // start server

ROUTER PLUGIN SYSTEM

to be completed... see the 'USAGE' section for example

API

to be completed... see the 'USAGE' section for example