thomas-crane / overnight

TypeScript decorators for the ExpressJS Server.

OvernightJS

TypeScript decorators for the ExpressJS Web Server!

What is it

OvernightJS is a simple library to add TypeScript decorators for methods meant to call Express routes. It also includes a package for managing json-web-tokens and printing logs.

Features

• Define a base route using a @Controller decorator.
• Decorators to convert class methods to Express routes (@Get, @Put, @Post, @Delete etc).
• Method decorators also work with arrow functions set as class properties.
• @Middleware and @ClassMiddleware decorators.
• Add options to controllers the same as you would Express routers with @ClassOptions.
• Support for child-controllers with @ChildControllers.
• @Wrapper and @ClassWrapper decorators to wrap functions.
• Server superclass to initialize ExpressJS server and setup controllers.
• Allows for adding your own custom Router classes if you don't want to use the standard express Router.
• Easy to configure logging tool.
• Json-Web-Token management.
• Master repo includes a sample application, if you want to practice with an API calling tool such as Postman.
• Compatible with both es5 and es6.
• Fully type safe :)

Why OvernightJS

OvernightJS isn't meant to be a replacement for Express. If you're already somewhat familiar with ExpressJS, you can learn Overnight in about 10 minutes. There are some other frameworks which do add decorators for Express such as NestJS and TsExpressDecorators, but these are massive frameworks with entire websites dedicated to their documentation. OvernightJS is clean, simple, and aside from the decorators, you can interact with ExpressJS in the same way you would any other Node application.

Table of Contents

• OvernightJS/core
• OvernightJS/logger
• OvernightJS/jwt

Installation

You can get the latest release using npm:

$ npm install --save @overnightjs/core express 
$ npm install --save-dev @types/express

Important! OvernightJS requires Node >= 6, Express >= 4, TypeScript >= 2.0 and the experimentalDecorators, lib compilation options in your tsconfig.json file.

Quick start

Create your controller

import { OK, BAD_REQUEST } from 'http-status-codes';
import { Controller, Middleware, Get, Post, Put, Delete } from '@overnightjs/core';
import { Request, Response } from 'express';
import { Logger } from '@overnightjs/logger';

@Controller('api/users')
export class UserController {

    @Get(':id')
    private get(req: Request, res: Response) {
        Logger.Info(req.params.id);
        return res.status(OK).json({
            message: 'get_called',
        });
    }

    @Get('')
    @Middleware([middleware1, middleware2])
    private getAll(req: ISecureRequest, res: Response) {
        Logger.Info(req.payload, true);
        return res.status(OK).json({
            message: 'get_all_called',
        });
    }

    @Post()
    private add(req: Request, res: Response) {
        Logger.Info(req.body, true);
        return res.status(OK).json({
            message: 'add_called',
        });
    }

    @Put('update-user')
    private update(req: Request, res: Response) {
        Logger.Info(req.body);
        return res.status(OK).json({
            message: 'update_called',
        });
    }

    @Delete('delete/:id')
    private delete(req: Request, res: Response) {
        Logger.Info(req.params, true);
        return res.status(OK).json({
            message: 'delete_called',
        });
    }

    @Get('practice/async')
    private async getWithAsync(req: Request, res: Response) {
        try {
            const asyncMsg = await this.asyncMethod(req);
            return res.status(OK).json({
                message: asyncMsg,
            });
        } catch (err) {
            Logger.Err(err, true);
            return res.status(BAD_REQUEST).json({
                error: err.message,
            });
        }
    }

    private asyncMethod(req: Request): Promise<string> {
        return new Promise((resolve) => {
            resolve(req.originalUrl + ' called');
        });
    }
}

• You don't have to use class methods, you can also use class properties whose value is an arrow function. You will have to cast Overnight to the 'any' type to avoid type errors though.

import * as OvernightJS from '@overnightjs/core';

    ...

    @(OvernightJS as any).Get('arrow/:id')
    private get = (req: Request, res: Response) => {
        this.logger.info(req.params.id);
        return res.status(200).json({msg: 'get_arrow_called'});
    }

• If you want your middleware to apply to every route in a class use the @ClassMiddleware decorator.

import { Controller, ClassMiddleware } from '@overnightjs/core';

@Controller('api/users')
@ClassMiddleware([middleware1, middleware2])
export class UserController {
    
    ...
}

• Child-controllers can be added with the @ChildControllers decorator. There's no limit to how many levels of nesting you can add. Make sure to instantiate them before adding them. Options at the class level can be added with @ClassOptions decorator.

import { Controller, ClassOptions, ChildControllers } from '@overnightjs/core';
import { ChildController1, ChildController2 } from '...'

@Controller('api/users')
@ClassOptions({mergeParams: true})
@ChildControllers([
    new ChildController1(), 
    new ChildController2(),
])
export class ParentController {
    
    ...
}

• You can wrap each class method in a custom function with the @Wrapper decorator. If you use the @ClassWrapper decorator then every method in that class will be wrapped with the provided method.

import * as expressAsyncHandler from 'express-async-handler';
import { ClassWrapper, Controller, Get, Wrapper } from '@overnightjs/core';
import { Request, Response } from 'express';

@Controller('wrapper-practice')
// Or instead of using @Wrapper below you could use @ClassWrapper here
export class WrapperController {
    
    @Get('async-third-party/:id')
    @Wrapper(expressAsyncHandler)
    private async asyncThirdParty(req: Request, res: Response) {
        const asyncMsg = await someAsyncFunction();
        return res.status(200).json({
            message: asyncMsg,
        });
    }
}

Import your controllers into the server

OvernightJS provides a Server superclass which initializes a new ExpressJS application. The express object is accessed using this.app, which is a protected, readonly class variable. You can interact with this variable like you would any normal express Application created with require('express')(). If you want to print to the console the name of each controller that has been successfully configured, set showLogs to true via the this.showLogs setter or the Server constructor().

super.addControllers() must be called to enable all of the routes in your controller. Make sure to call it after setting up your middleware. You can pass super.addControllers() a single controller-instance or an array of controller-instances, but they must be instantiated first.

import * as bodyParser from 'body-parser';
import { Server } from '@overnightjs/core';
import { Logger } from '@overnightjs/logger';
import { UserController } from './UserController';
import { SignupController } from './SignupController';

export class SampleServer extends Server {
    
    constructor() {
        super(process.env.NODE_ENV === 'development'); // setting showLogs to true
        this.app.use(bodyParser.json());
        this.app.use(bodyParser.urlencoded({extended: true}));
        this.setupControllers();
    }

    private setupControllers(): void {
        const userController = new UserController();
        const signupController = new SignupController();
        const dbConnObj = new SomeDbConnClass('credentials');
        signupController.setDbConn(dbConnObj);
        userController.setDbConn(dbConnObj);
        // super.addControllers() must be called, and can be passed a single controller or an array of 
        // controllers. Optional router object can also be passed as second argument.
        super.addControllers([userController, signupController]/*, optional router here*/);
    }

    public start(port: number): void {
        this.app.listen(port, () => {
            Logger.Imp('Server listening on port: ' + port);
        })
    }
}

IMPORTANT NOTE: If you initialize environment variables from some script which imports the Server script, those environment variables must be configured before importing the Server script or else they could end up undefined for nested controllers.

See how awesome this is!

Without the above decorators we would have to wrap each controller method with something like:

/* In the controller file*/
class UserController {
    
    public getRoutes(): Router {
        const router = Router();
        router.get('/', [your middleware], (req, res) => {
            // Do some stuff in here
        });
        router.get('/anotherRoute', [other middleware], (req, res) => {
            // Do some stuff in here
        });
        // Repeat for every single controller method
        return router;
    }
}

let userController = new UserController();
this.app.use('/api/users', userController.getRoutes());
// Repeat for every single controller class

This would get really tedious overtime and lead to a lot of boiler plate code.

Using a Custom Router

Suppose you don't want to use the built in "Router" object which is provided by Express. Maybe you want use express-promise-router because you don't like using try/catch blocks. OvernightJS allows you to pass in a custom router object in the super.addControllers() method. Simply pass in your custom router as the second param after the controller-instance/s. When you don't specify a custom router, the default express.Router() object is used.

• Controller using express-promise-router:

import { Request, Response } from 'express';
import { Controller, Get } from '@overnightjs/core';

@Controller('api/posts')
export class PostController {

    @Get(':id')
    private get(req: Request, res: Response) {
        return this.someAsyncFunction(req.params.id)
                    .then(ret => res.status(200).json({msg: ret}));
    }

    private someAsyncFunction(id: number): Promise<string> {
        return new Promise((res, rej) => {
            isNaN(id) ? rej('Invalid id') : res('Valid id');
        })
    }
}

• Add express-promise-router in the super.addControllers() method:

import * as customRouter  from 'express-promise-router';
import { Server } from '@overnightjs/core';
import { PostController } from './controllers/PostController';

export class CustomRouterServer extends Server {
    
    constructor() {
        super();
        super.addControllers(new PostController(), customRouter); // <-- custom router added here
    }

    ...
}

OvernightJS/logger

Despite the abundance of logging tools out there, knowing exactly which is the right one for your web-server might take more time than you feel like spending. So you can start logging events right away, OvernightJS comes with its own logging package. From the environment variables you can easily switch your logs to be printed out to the command line, a file, sent through your own custom logging logic, or turned off completely. Logs printed to the console also are printed out in different colors depending on whether they're info, a warning, an error, etc. The file for holding logs can be specified manually or left as the default. Let's check it out!

Installation

$ npm install --save @overnightjs/logger

Guide

The logger package's main export is the Logger class. Logger can used statically or as an instance with settings configured through a constructor.

• The three environment variables are:
  • OVERNIGHT_LOGGER_MODE: can be 'CONSOLE'(default), 'FILE', 'CUSTOM', and 'OFF'.
  • OVERNIGHT_LOGGER_FILEPATH: the file-path for file mode. Default is home_dir/overnight.log.
  • OVERNIGHT_LOGGER_RM_TIMESTAMP: removes the timestamp next to each log. Can be 'TRUE' or 'FALSE'(default).

logger has an export LoggerModes which is an enum that provides all the modes if you want to use them in code. I would recommend using Console for local development, File for remote development, and Custom or Off for production. If you want to change the settings in code, you can do so via the constructor or getters/setters.

• There are 4 functions on Logger to print logs. Each has a static counterpart:
  • info or Info: prints green.
  • imp or Imp: prints magenta.
  • warn or Warn: prints yellow.
  • err or Err: prints red.

There is an optional second param to each method which is a boolean. If you pass true as the second param, Logger will use node's util so that the full object gets printed. You should NOT normally use this param, but it is especially useful when debugging errors so that you can print out the full error object and observe the stack trace.

Let's look at a code sample which sets the environment variables via a start script:

• In the start script

import * as path from 'path';
import * as fs from 'fs';
import { LoggerModes } from '@overnightjs/logger';

// Set the 
const logFilePath = path.join(__dirname, '../sampleProject.log');
process.env.OVERNIGHT_LOGGER_MODE = LoggerModes.File; // Can also be Console, Custom, or Off
process.env.OVERNIGHT_LOGGER_FILEPATH = logFilePath;

// Remove current log file if it exists
(function removeFile() {
    try {
        fs.unlinkSync(logFilePath);
    } catch (e) { return; }
})();

• In the controller file

import { OK } from 'http-status-codes';
import { Request, Response } from 'express';
import { Controller, Get } from '@overnightjs/core';
import { Logger } from '@overnightjs/logger';

@Controller('api/logger')
export class LoggerPracticeController {
    
    private readonly logger: Logger;
    
    constructor() {
        this.logger = new Logger();
    }

    @Get('static/console/:msg')
    private printLogsConsole(req: Request, res: Response) {
        Logger.Info(req.params.msg);
        Logger.Imp(req.params.msg);
        Logger.Warn(req.params.msg);
        Logger.Err(req.params.msg);
        Logger.Err(new Error('printing out an error'));
        Logger.Err(new Error('printing out an error full'), true); // <-- print the full Error object
        return res.status(OK).json({
            message: 'static_console_mode',
        });
    }
    
    @Get('console/:msg')
    private printLogsConsole(req: Request, res: Response) {
        this.logger.info(req.params.msg);
        this.logger.imp(req.params.msg);
        this.logger.warn(req.params.msg);
        this.logger.err(req.params.msg);
        this.logger.err(new Error('printing out an error'));
        this.logger.err(new Error('printing out an error full'), true);
        return res.status(OK).json({
            message: 'console_mode',
        });
    }
}

• The previous code-snippet will show the following content when printed to a file:

IMPORTANT: [2019-04-07T19:17:28.799Z]: OvernightJS with standard express router started on port: 3000
INFO: [2019-04-07T19:18:08.939Z]: hello-logger
IMPORTANT: [2019-04-07T19:18:08.939Z]: hello-logger
WARNING: [2019-04-07T19:18:08.939Z]: hello-logger
ERROR: [2019-04-07T19:18:08.940Z]: hello-logger
ERROR: [2019-04-07T19:18:08.940Z]: Error: printing out an error
ERROR: [2019-04-07T19:18:08.956Z]: Error: printing out an error full
    at class_1.LoggerPracticeController.printLogsFile (/home/seanmaxwell/WebstormProjects/Overnight/sample-project/src/controllers/LoggerPracticeController.ts:49:20)
    at class_1.descriptor.value [as printLogsFile] (/home/seanmaxwell/WebstormProjects/Overnight/src/core/lib/PropertyDecorators.ts:36:35)
    at callBack (/home/seanmaxwell/WebstormProjects/Overnight/src/core/lib/Server.ts:78:50)
    at Layer.handle [as handle_request] (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/layer.js:95:5)
    at next (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/route.js:137:13)
    at Route.dispatch (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/route.js:112:3)
    at Layer.handle [as handle_request] (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/layer.js:95:5)
    at /home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/index.js:281:22
    at param (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/index.js:354:14)
    at param (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/index.js:365:14)
    at Function.process_params (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/index.js:410:3)
    at next (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/index.js:275:10)
    at Function.handle (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/index.js:174:3)
    at router (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/index.js:47:12)
    at Layer.handle [as handle_request] (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/layer.js:95:5)
    at trim_prefix (/home/seanmaxwell/WebstormProjects/Overnight/src/core/node_modules/express/lib/router/index.js:317:13)

• And this when printed to the console:

Using a custom logger

For production you'll probably have some third party logging tool like ElasticSearch or Splunk. logger exports one interface ICustomLogger which has one method sendLog() that needs to implemented. If you created a class which implements this interface, and add it to Logger through a setter or the constructor, and set the mode to CUSTOM, Logger will call whatever logic you created for sendLog().

// CustomLoggerTool.ts
import { ICustomLogger } from '@overnightjs/logger';

export class CustomLoggerTool implements ICustomLogger {

    private readonly thirdPartyLoggingApplication: ThirdPartyLoggingApplication;

    constructor() {
        this.thirdPartyLoggingApplication = new ThirdPartyLoggingApplication();
    }

    // Needs to be implemented
    public sendLog(content: any): void {
        this.thirdPartyLoggingApplication.doStuff(content);
    }
}

    // In the controller file
    
    ...

    @Get('useCustomLogger/:msg')
    private useCustomLogger(req: Request, res: Response) {
        const logger = new Logger(LoggerModes.CUSTOM, '', true, this.customLoggerTool);
        logger.rmTimestamp = true;
        logger.info(req.params.msg);
        return res.status(OK).json({
                    message: 'console_mode',
                });
    }

OvernightJS/jwt

What is it

This is an easy tool for removing boilerplate code around json-web-tokens (jwt). You can get your token and middleware with just one line of code. @overnightjs/core is a sister library to add TypeScript decorators for methods meant to call Express routes and is not required for @overnightjs/jwt but they do work beautifully together.

Features

• JwtManager class which, when when used statically, can pull the JWT expiration and secret from the environment variables.
• When used as an instance-object, JwtManager can be dynamically passed the JWT expiration and secret if you prefer to set them through the code.
• Default values for the secret and expiration when used statically. This is convenient for a development environment.
• Fully type-safe :)

Installation

$ npm install --save @overnightjs/jwt express 
$ npm install --save-dev @types/express @types/express-jwt @types/jsonwebtoken

Table of Contents

• Option 1
• Option 2

Option 1: Environment Variables

This is what really saves you from having to do boilerplate code. The two environment variables you need to set are OVERNIGHT_JWT_SECRET and OVERNIGHT_JWT_EXP. OVERNIGHT_JWT_SECRET should be a really long, random string (recommended is 80 characters) and the rules for setting OVERNIGHT_JWT_EXP are the same as setting the expiration time for the jsonwebtoken library. The rules are:

If you use a string be sure you provide the time units (days, hours, etc), otherwise milliseconds is used by default ("120" is equal to "120ms"). Examples: "2 days", "10h", "7d".

How you set your environment variables will vary depending on the which environment you are working in. I use Ubuntu which is pretty easy. Just open the /etc/environment file and type:

OVERNIGHT_JWT_SECRET="your super long random string"
OVERNIGHT_JWT_EXP="your expiration time"

Another common option is the dotenv library, which imports environment variables from a .env file

If you do not set these environment variables, a default value of '3 days' will be set for the expiration time and a random string will be generated for the secret. The random string is fine for development but do not use it for production. Every time you restart the server the secret will change and all client-side JWTs will become invalid.

Now let's create the controller. The data that is encrypted is stored as the payload property. That's all there is to it. Just import JwtManager.

import { OK } from 'http-status-codes';
import { JwtManager, ISecureRequest } from '@overnightjs/jwt';
import { Controller, Middleware, Get, Post } from '@overnightjs/core';
import { Request, Response } from 'express';

@Controller('api/jwt')
export class JwtPracticeController {
    
    @Get(':email')
    private getJwt(req: Request, res: Response) {
        const jwtStr = JwtManager.jwt({
            email: req.params.email
        });
        return res.status(OK).json({
            jwt: jwtStr,
        });
    }

    @Post('callProtectedRoute')
    @Middleware(JwtManager.middleware)
    private callProtectedRoute(req: ISecureRequest, res: Response) {
        return res.status(OK).json({
            email: req.payload.email,
        });
    }
}

Option 2: Pass through the constructor

If you want to set your secret and expiration time manually, you can instantiate the JwtManager class and set them via the constructor. I love using Option 1 way more, but I thought I'd supply this option for people who prefer to import it another way.

import { OK } from 'http-status-codes';
import { JwtManager, ISecureRequest } from '@overnightjs/jwt';
import { Controller, Middleware, Get, Post } from '@overnightjs/core';
import { Request, Response } from 'express';

const jwtMgr = new JwtManager('secret', '10h');

@Controller('api/jwt')
export class JwtPracticeController {
    
    @Get('getJwtAlt/:fullname')
    private getJwtFromHandler(req: Request, res: Response) {
        const jwtStr = jwtMgr.jwt({
            fullName: req.params.fullname
        });
        return res.status(OK).json({
            jwt: jwtStr,
        });
    }

    @Post('callProtectedRouteAlt')
    @Middleware(jwtMgr.middleware)
    private callProtectedRouteFromHandler(req: ISecureRequest, res: Response) {
        return res.status(OK).json({
            fullname: req.payload.fullName,
        });
    }
}

Works just as fine in regular Express

You dont have to use @overnightjs/jwt with @overnightjs/core. If you're using Express but are not interested in using decorators, you can pass the middleware just the same as you would for any typical Express Router object.

const router = express.Router();

router.get('users', JwtManager.middleware, (req, res) => {
    console.log(req.payload.email);
})

app.use('/', router); 

That's All!!

Please star this repo if you found it useful. Happy web-deving :)

License

MIT