TsExpressDecorators

Build your TypeScript v2 application with Express decorators ! Support ES5 and ES6.

Table of contents

• Features
• Quick start
• Injection
• Use promise
• Custom middleware
• Authentification
• Throw HTTP exceptions
• Global errors handler
• Decorators references
• License

Features

• Define classe as Controller,
• Define root path for an entire controller,
• Define as sub-route path for a method,
• Define routes on GET, POST, PUT and DELETE verbs,
• Define middlewares on routes,
• Define required parameters,
• Inject data from query string, path parameters, entire body, cookies or header,
• Inject Request, Response, Next object from Express request.

Quick start

Prerequisites

ts-route-decorators require :

• TypeScript 2.0.2 and experimentalDecorators must be to set at true,
• Node v4 or higher,
• NPM v2 or higher.

Installation

You need to install the typescript compiler and typings tools to developp your app in TypeScript. So run :

$ npm install -g typescript@2.0.2

Then configure your tsconfig.json, to compile the typescript file :

{
  "compilerOptions": {
    "module": "commonjs",
    "target": "es5",
    "noImplicitAny": false,
    "sourceMap": true,
    "declaration":false,
    "experimentalDecorators":true,
    "emitDecoratorMetadata": true,
    "moduleResolution": "node",
    "isolatedModules": false,
    "noLib": false,
    "suppressImplicitAnyIndexErrors": false,
    "lib": ["es6"]
  },
  "exclude": [
    "node_modules"
  ]
}

Note : Target can be set to es2015/ES6. You can use pure es6 API with ts-express-decorators/es6.

Finally run command this command to install ts-express-decorators in your project :

$ npm install --save ts-express-decorators express@4

Configuration

Create your express server

ts-express-decorators provide a ServerLoad class to configure your express quickly. Just create a server.ts in your root project, declare a new Server class that extends ServerLoader.

import * as Express from "express";
import {ServerLoader} from "ts-express-decorators/server-loader";
import Path = require("path");

export class Server extends ServerLoader {
    /**
     * In your constructor set the global endpoint and configure the folder to scan the controllers.
     * You can start the http and https server.
     */
    constructor() {
        super();

        let appPath: string = Path.resolve(__dirname);
        
        this.setEndpoint("/rest")                       // Declare your endpoint
            .scan(appPath + "/controllers/**/**.js")    // Declare the directory that contains your controllers
            .createHttpServer(8000)
            .createHttpsServer({
                port: 8080
            });

    }

    /**
     * This method let you configure the middleware required by your application to works.
     * @returns {Server}
     */
    public importMiddlewares(): Server {
        let morgan = require("morgan"),
            cookieParser = require("cookie-parser"),
            bodyParser = require("body-parser"),
            compress = require("compression"),
            methodOverride = require("method-override"),
            session = require("express-session");

        this
            .use(morgan("dev"))
            .use(ServerLoader.AcceptMime("application/json"))
            .use(bodyParser.json())
            .use(bodyParser.urlencoded({
                extended: true
            }))
            .use(cookieParser())
            .use(compress({}))
            .use(methodOverride());

        return this;
    }

    /**
     * Start your server. Enjoy it !
     * @returns {Promise<U>|Promise<TResult>}
     */
    static Initialize(): Promise<any> {

        log.debug("Initialize server");

        return new Server()
            .start()
            .then(() => {
                log.debug("Server started...");
            });
    }
    
}

Server.Initialize();

Create your first controller

Create a new calendarCtrl.ts in your controllers directory configured previously with ServerLoader.scan(). All controllers declared with @Controller decorators is considered as an Express router. An Express router require a path (here, the path is /calendars) to expose an url on your server. More precisely, it is a part of path, and entire exposed url depend on the Server configuration (see ServerLoader.setEndpoint()) and the controllers dependencies. In this case, we haven't a dependencies and the root endpoint is set /rest. So the url of this controller will be http://host/rest/calendars.

import {Controller, Get} from "ts-express-decorators";
import * as Express from "express";

interface ICalendar{
    id: string;
    name: string;
}

@Controller("/calendars")
export class CalendarCtrl {

    /**
     * Example of classic call. Use `@Get` for routing a request to your method.
     * In this case, this route "/calendars/:id" are mounted on the "rest/" path.
     *
     * By default, the response is sent with status 200 and is serialized in JSON.
     *
     * @param request
     * @param response
     * @returns {{id: any, name: string}}
     */
    @Get("/:id")
    public get(request: Express.Request, response: Express.Response): ICalendar {

        return <ICalendar> {id: request.params.id, name: "test"};
    }
    
    @Authenticated()
    @BodyParamsRequired("calendar.name")  // Throw Bad Request (400) if the request.body.calendar.name isn't provided 
    @Post("/")
    public post(
        @BodyParams("calendar") calendar: ICalendar
    ): Promise<ICalendar> {
    
        return new Promise((resolve: Function, reject: Function) => {
        
            calendar.id = 1;
            
            resolve(calendar);
            
        });
    }
    
    @Authenticated()
    @Delete("/")
    public post(
        @BodyParams("calendar.id") @Required() id: string 
    ): Promise<ICalendar> {
    
        return new Promise((resolve: Function, reject: Function) => {
        
            calendar.id = id;
            
            resolve(calendar);
            
        });
    }
}

To test your method, just run your server.ts and send a http request on /rest/calendars/1.

Note : Decorators Get support dynamic pathParams (see /:id) and RegExp like Express API.

Injection

Response and Request services

You can use decorator to inject Express.Request, Express.Response and Express.NextFunction services instead of the classic call provided by Express API. Just use decorator Request, Response and Next on your method parameters like this :

import {Controller, Get, Response, Request, Next} from "ts-express-decorators";
import * as Express from "express";

interface ICalendar{
    id: string;
    name: string;
}

@Controller("/calendars")
export class CalendarCtrl {

    @Get("/:id")
    public get(
        @Request() request: Express.Request, 
        @Response() response: Express.Response,
        @Next() next: Express.NextFunction
    ): void {
    
        setTimeout(() => {
            response.send(200, {id: request.params.id, name: "test"});
            next();
        });

    }
}

PathParams, BodyParams, QueryParams services

@PathParams decorator provide you a quick access to an attribute Express.request.params.

import {Controller, Get, Response, PathParams} from "ts-express-decorators";
import * as Express from "express";

@Controller("/calendars")
export class CalendarCtrl {

    @Get("/:id")
    public get(
        @PathParams("id") id: number, 
        @Response() response: Express.Response,
        @Next() next: Express.NextFunction
    ): void {
    
        setTimeout(() => {
            response.send(200, {id: id, name: "test"});
            next();
        });

    }
}

Same decorator are available to get other params. Use BodyParams (with the right HTTP verb @Post, @Put, etc...), QueryParams or CookiesParams to get parameters send by the client.

Header Service

@Header decorator provide you a quick access to the Express.request.get()

import {Controller, Get, Response, PathParams} from "ts-express-decorators";
import * as Express from "express";

@Controller("/calendars")
export class CalendarCtrl {

    @Get("/:id")
    public get(
        @Header("x-token") token: string,
        @PathParams("id") id: number
    ): any {
    
        console.log("token", token);
        return {id: id};
    }
}

Use promise

ts-express-decorators support Promise API to send a response. Just return a promise in your method and the controller will be waiting your promised response before send a response to the client.

import {Controller, Get, Response, Request} from "ts-express-decorators";
import * as Promise from "bluebird";
import * as Express from "express";

interface ICalendar{
    id: string;
    name: string;
}

@Controller("/calendars")
export class CalendarCtrl {

    @Get("/:id")
    public get(
        @Request() request: Express.Request, 
        @Response() response: Express.Response
    ): Promise<ICalendar> {
    
        return new Promise<ICalendar>((resolve: Function, reject: Function) => {
        
            // you can modify status with response.status(202);

            resolve({
                id: id,
                name: "test"
            });
        });

    }
}

Custom middleware

@Use() decoratore let you to add custom middleware on a method.

import {Controller, Get, PathParams} from "ts-express-decorators";
import {BadRequest} from "httpexceptions";
import * as Express from "express";

@Controller("/calendars")
export class CalendarCtrl {

    @Get("/:id")
    @Use(CalendarCtrl.middleware)
    public get(
        @PathParams("id") id: number
    ): any {
      
       
       return {id: id};
    }
    
    static middleware(request, response, next) {
    
        console.log(request.params.id); 
        next();
    }
}

Note : Middle can't use injectable service like the CalendarCtrl.get() method actually.

Authentification

The @Authentification use a ServerLoader.isAuthenticated() method to check the authentification strategy. You can configure this method by adding an isAuthenticated() method on your Server class.

import * as Express from "express";
import {ServerLoader} from "ts-express-decorators/server-loader";
import Path = require("path");

export class Server extends ServerLoader {

    /**
     * Set here your authentification strategy.
     * @param request
     * @param response
     * @param next
     * @returns {boolean}
     */
    public isAuthenticated(request: Express.Request, response: Express.Response, next: Express.NextFunction): boolean {


        return true;
    }
}

Throw HTTP Exceptions

You can use (httpexceptions)[https://github.com/Romakita/httpexceptions] or similar module to throw an http exception.

import {Controller, Get, PathParams} from "ts-express-decorators";
import {BadRequest} from "httpexceptions";
import * as Express from "express";

@Controller("/calendars")
export class CalendarCtrl {

    @Get("/:id")
    public get(
        @PathParams("id") id: number
    ): any {
    
        if (!IsNaN(+id)) {
            throw(new BadRequest("Not a number"));
        }
       
       return {id: id};
    }
}

Global Errors Handler

All errors are intercepted by the ServerLoader class. By default, all HTTP Exceptions are automatically sent to the client, and technical error are sent as Internal Server Error.

You can override the default method by adding onError method your Server class.

import * as Express from "express";
import {ServerLoader} from "ts-express-decorators/server-loader";
import Path = require("path");

export class Server extends ServerLoader {

    
    /**
     * Customize this method to manage all errors emitted by the server and controllers.
     * @param error
     * @param request
     * @param response
     * @param next
     */
    public onError(error: any, request: Express.Request, response: Express.Response, next: Function): void {

        console.error(error);

        return super.onError(error, request, response, next);
    }
}

Decorators references

Class decorators

• @Controller(route: string, ...ctrlsNamesDepedencies?: string[]) : Declare a new controller with his Rest path.

Method decorators

• @All(route): Intercept all request for a given route.
• @Get(route): Intercept request with GET http verb for a given route.
• @Post(route): Intercept request with POST http verb for a given route.
• @Put(route): Intercept request with PUT http verb for a given route.
• @Delete(route): Intercept request with DELETE http verb for a given route.
• @Head(route): Intercept request with HEAD http verb for a given route.
• @Patch(route): Intercept request with PATCH http verb for a given route.
• @Authenticated(): Call the Server.isAuthenticated method to check if the user is authenticated.
• @Use(...middlewares: any[]): Set a custom middleware.

Parameter Decorators

• @Response(): Express.Response service.
• @Request(): Express.Request service.
• @Next(): Express.NextFunction service.
• @PathParams(expression: string): Get a parameters on Express.Request.params attribut.
• @BodyParams(expression: string): Get a parameters on Express.Request.body attribut.
• @CookiesParams(expression: string): Get a parameters on Express.Request.cookies attribut.
• @QueryParams(expression: string): Get a parameters on Express.Request.query attribut.
• @Required(): Set a required flag on parameters.

Deprecated :

• @PathParamsRequired(...expression: string[]): Throw bad request if the parameter(s) isn't provided.
• @BodyParamsRequired(...expression: string[]): Throw bad request if the parameter(s) isn't provided.
• @CookiesParamsRequired(...expression: string[]): Throw bad request if the parameter(s) isn't provided.
• @QueryParamsRequired(...expression: string[]): Throw bad request if the parameter(s) isn't provided.

Use @Required instead.

License

The MIT License (MIT)

Copyright (c) 2016 Romain Lenzotti

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.