Skalavel

Skalavel is a typescript framework to create complete and scalables (skalavel) web applications.

Create a simple project

To create a simple project use the skalavel npm package:

mkdir my-skalavel-app
cd my-skalavel-app
npm init -y
npm install skalavel

Now create a file named index.js:

// Import the necesary classes.
// - Server - Create a server
// - Router - Create a router in the server
// - Controller - Create a web controller
// - controllerLoader - Load a controller for the router, this is a function
// - log - An instance of the Log class to print with colours format
const { Server, Router, Controller, controllerLoader, log } = require('skalavel');

// Create a controller class named MainController, it has two methods
// the first method respond with a html response, and the second method
// respond with a json response.
class MainController extends Controller {
  html() {
    this.htmlRes('<h1>Hello, Skalavel!</h1>');
  }

  json() {
    this.jsonRes({ json: true });
  }
}

// Create the server and the router instances
const server = new Server();
const router = new Router();

// Now create the routes and load the MainController, calling the html method
// and the json method, the routes has the same names of the methods
router.get('/', controllerLoader(MainController, 'home')); // home, because the method of controller is named "home"
router.get('/json', controllerLoader(MainController, 'json')); // json, because the method of controller is named "json"

// Load the router in the server
server.setRouter(router);

// Listen the server, and print with colours using the log skalavel library, pass
// the port, and then a callback.
const PORT = 8000;

server.listen(PORT, () => {
  log.success(`Server is listening successfully on port ${PORT}`);
});

Explaining

In this example, we view a lot of concepts:

• Server

With the server you must create a http server, the main proposite of the server, is load the router, and listen the application in a specified port.

• Router

The router create the routes for the server. The router is manually integrated with the server (use the Server.setRouter method). To load the controllers use the controllerLoader function as this:

router.get('/get', controllerLoader(MyController, 'getRoute'));
router.post('/post', controllerLoader(MyController, 'postRoute'));
router.put('/put', controllerLoader(MyController, 'putRoute'));
router.delete('/delete', controllerLoader(MyController, 'deleteRoute'));

The methods of the router are:

• get (parameters: url, callback)
• post (parameters: url, callback)
• put (parameters: url, callback)
• delete (parameters: url, callback)

The internal methods of the router are:

• _createRoute (parameters: method, url, callback)

The internal properties of the router are:

• _register (The routes register)

• log (Log)

The log contains a methods for show pretty printed logs (with colours), the methods of the log library are:

• success (green)

• error (red & exit with statuscode 1)

• warning (yellow)

• info (blue)

• Controller - controllerLoader

The Controller class contains a methods for create a web controller, the controllerLoader, process the Controller _register and pass it to the router, the router validate the _register object, and pass it to the server, rendering your response. The methods of the Controller class are:

• htmlRes - Send a html response
• jsonRes - Send a json response
• redirect - Redirect to a passed url

Methods arguments:

• htmlRes: (response: string, statuscode: number)
• jsonRes: (response: string, statuscode: number)
• redirect (url: string)

The internal methods are:

• _rawRes - Send a raw or custom response, parameters: (response: string, headers: object, statuscode: number)

The internal data are:

• req - The http req object (express.Request)
• _register - The controller history register, it's processed by the controller loader

The controllerLoader, receive this parameters:

• Controller (skalavel.Controller) - A class extending the skalavel.Controller class.
• method (string) - The method to execute (in string format) of the Controller parameter

Using skalavel with typescript

To use skalavel with typescript, see the following steps:

• Setup a typescript project

mkdir ~/my-skalavel-typescript-project
cd ~/my-skalavel-typescript-project
yarn init -y
yarn add -D typescript @types/node ts-node nodemon
yarn add skalavel
# Edit the package.json
vim package.json

Configure the start and the build and the dev command.

{
  "scripts": {
    "start": "node dist/index.js",
    "build": "tsc",
    "dev": "nodemon --exec ts-node dist/index.js --watch src --ext .js,.ts"
  }
}

Create a typescript project with tsc:

npx tsc --init
# Edit the tsconfig.json
vim tsconfig.json

Place this content on this:

{
  "compilerOptions": {
    "target": "es5",
    "module": "commonjs",
    "downlevelIteration": true,
    "outDir": "./dist",
    "rootDir": "./src",
    "strict": true
  },
  "exclude": ["node_modules", "**/__tests__/*"]
}

Now create a src and dist folders and edit the src/index.ts file (create it!)

mkdir src dist
touch src/index.ts
vim src/index.ts

Place this content in it file:

// Import all necesary elements
import { Server, Router, Controller, controllerLoader, log } from 'skalavel';

// Create the interface of the MainController, type anotations for controller
interface IMainController {
  html(): void;
  json(): void;
  redirection(): void;
}

// Create the `MainController` and implement `IMainController`
class MainController extends Controller implements IMainController {
  html(): void {
    this.htmlRes('<h1>Hello, World!</h1>');
  }

  json(): void {
    this.jsonRes({ json: true });
  }

  redirection(): void {
    // Redirect to /, rendering a html response
    this.redirect('/');
  }
}

// Define the app constants
const PORT: number = 8000;

// Create the server and the router
const server: Server = new Server();
const router: Router = new Router();

// Create the routes using the router and the controllerLoader
router.get('/', controllerLoader(MainController, 'html'));
router.get('/json', controllerLoader(MainController, 'json'));
router.get('/redirection', controllerLoader(MainController, 'redirection'));

// Load the router on the server
server.setRouter(router);

// Listen the server
server.listen(PORT, (): void => {
  log.success(`Server is listening on port ${PORT}`);
});

Now execute your app on develop mode:

yarn dev

Go to localhost:8000 and test this routes:

• / - Render a html response
• /json - Render a json response
• /redirection - Redirect to /

If the web browser is keep loading infinity, please report it on a issue (place your code!)

NOTE: The possibly problem is in the router, or you are visiting a not found page (the not found page (404) does not exists)

If you want to compile your application for production use this commands sequence:

yarn build
yarn start

It create a folder named dist in it exists the file index.js (the compiled code)

NOTE: Between this, all code is writed on typescript

Skalavel Tasks

The tasks are functions that executes before the server listen, to create it use the skalavel.Task class, and extend it as this:

import { Task, log } from 'skalavel';

class PrintPortTask extends Task {
  // All tasks main function is named run
  run(): void {
    log.info('The server is programmed to run in the port 8000');
  }
}

Now load it on the server, like this:

server.setTasks([PrintPortTask])

It is all, your tasks are executed before the server listen.

Thank you

Skalavel is in develop. The features to the future are:

• Middlewares
• Router
  • Get routes (with parameters)
  • Delete routes (with parameters)

This "framework" is inspired in archos.js, why I rewrite archos.js in typescript.

Skalavel is rewrited because:

• Archos.js is too unmaintainable
• Archos.js is not in npmjs
• Archos.js is not multiplatform

Now Skalavel is to manually to programming, I'm engaged to create a cli (like Archos.js cli) for skalavel, but in npm

Changelog

Version 0.1.1:

• Created a global app state named global at skalavel package
• Created a environment parser (.env parser with dotenv) named env it load's all data in the global state

Version 0.1.2:

• Added Changelog to README.md

Version 0.1.3:

• Removed testing .env file

Version 0.1.4:

• Added an option in the environment library to get a parsed dotenv value

Version 0.1.5:

• Updated README.md

Version 0.1.6:

• Fixing README.md problems

Examples

Coming soon...