mvc-middleware

Mvc middleware for express like .Net Mvc

• Installation
• How to use
  • Dependency injection
  • Decorators
  • MvcController methods
  • More examples

Installation

npm i mvc-middleware

How to use

// src/index.ts
import { json } from 'body-parser';
import cors from 'cors';
import express from 'express';
import http from 'http';
import { MvcMiddleware } from 'mvc-middleware';
import path from 'path';

// Path to folder where you have your controllers.
// Middleware will search controllers recursively.
// Each file with '.ts' extension and default export and 
//  typeof === 'function', decorated with '@api' will be
//  assumed as controller class.
const controllersPath = path.join(__dirname, 'api');

const expressApp = express();
expressApp.use(cors()).use(json());

const mvcMiddleware = new MvcMiddleware(expressApp);

(async () => {
  await mvcMiddleware.registerControllers(controllersPath);

  http
    .createServer(expressApp)
    .listen(80, 'localhost');
})();

// src/api/UsersApi.ts
import { MvcController } from 'mvc-middleware';

@api('/api')
export default class UsersApi extends MvcController {
  @GET // api/users
  users() {
    return this.ok(['user-1', 'user-2', 'user-3']);
  }
}

// src/api/ArticlesApi.ts
import { MvcController } from 'mvc-middleware';

@api('/api')
export default class ArticlesApi extends MvcController {
  @GET // articles
  async articles() {
    const articles = await Promise.resolve(['article-1', 'article-2']);
    return this.ok(articles);
  }
}

Dependency injection

We recommend to use cheap-di package to handle your dependency injection:

import { container } from 'cheap-di';
import express from 'express';

const expressApp = express();
const mvcMiddleware = new MvcMiddleware(expressApp, container);
// ...

You may pass any custom DI resolver that implements the following contract:

type AbstractConstructor<T = any> = abstract new (...args: any[]) => T;
type Constructor<T = any> = new (...args: any[]) => T;

type Resolver = <TInstance>(type: Constructor<TInstance> | AbstractConstructor<TInstance>, ...args: any[]) => TInstance | undefined;

interface DependencyResolver {
  /** instantiate by class */
  resolve: Resolver;
}

Decorators

We have two sets of decorators: for stage 2 (legacy) and stage 3 proposals. You may choose one of them with imports:

import { api, GET, POST, PUT, PATCH, DELETE } from 'mvc-middleware/stage2';
import { api, GET, POST, PUT, PATCH, DELETE } from 'mvc-middleware/stage3';

| decorator | description | variants of using | |-----------|----------------------------------------------------------------------------|-------------------------------------------------------------------------------| | api | collect method names and types (get/post/...) and concat prefix to is urls | @api@api('api')@api('/api/domain') | | GET | marks method as handler for GET request, can change handled url | @GET@GET('')@GET('my-route')@GET('/my-route') | | POST | marks method as handler for GET request, can change handled url | @POST@POST('')@POST('my-route')@POST('/my-route') | | PUT | marks method as handler for PUT request, can change handled url | @PUT@PUT('')@PUT('my-route')@PUT('/my-route') | | PATCH | marks method as handler for PATCH request, can change handled url | @PATCH@PATCH('')@PATCH('my-route')@PATCH('/my-route') | | DELETE | marks method as handler for DELETE request, can change handled url | @DELETE@DELETE('')@DELETE('my-route')@DELETE('/my-route') |

MvcController methods

| Method name | Response status code | Response type | Arguments | Description | |:-------------------:|:--------------------:|:-------------:|:---------------------------------:|------------------------------------------------------------| | ok | 200 | text or json | model?: any | returns 200 status code with data | | created | 201 | text or json | model?: any | returns 201 status code with data | | accepted | 202 | text or json | model?: any | returns 202 status code with data | | noContent | 204 | - | - | returns 204 status code | | | | | | | | found | 302 | text | url: string | returns 302 status code | | permanentRedirect | 308 | text | url: string | returns 308 status code | | redirect | 300 - 308 | text | statusCode: number, url: string | returns redirection status code | | | | | | | | badRequest | 400 | text or json | model?: any | returns 400 status code with data | | unauthorized | 401 | text or json | model?: any | returns 401 status code with data | | forbid | 403 | - | model?: any | returns 403 status code | | notFound | 404 | text or json | model?: any | returns 404 status code with data | | conflict | 409 | text or json | model?: any | returns 409 status code with data | | | | | | | | serverError | 500 | text | message?: any | returns 500 status code with error message | | sendResponse | any http status code | text | model: any, statusCode?: number | returns status code with data. Default status code is 200 |

More examples

// src/api/UsersController.ts
import { Request, Response } from 'express';
import { api, GET, POST } from 'mvc-middleware/stage2';

@api('/api/users')
export default class UsersController extends MvcController {
  static users = [{
    id: 1,
    name: 'user 1',
  }]

  // GET: /api/users
  @GET('')
  list() {
    return this.ok(UsersController.users);
  }

  // GET: /api/users/:userId
  @GET(':userId')
  getById(stringId: string) {
    const userId = parseInt(stringId, 10);
    const user = UsersController.users.find(user => user.id === userId);
    return this.ok(user);
  }

  // POST: /api/users
  @POST('')
  add({ name }: { name: string }) {
    UsersController.users.push({
      id: UsersController.users.length + 1,
      name,
    });
    return this.ok('user is added');
  }
}

If you want to get query params and body content, you have to connect another middleware that will handle requests before MvcMiddleware like below.

// src/index.ts
import express, { Router } from 'express';
import bodyParser from 'body-parser';
import { MvcMiddleware } from 'mvc-middleware';

const expressApp = express();

expressApp.use(bodyParser.json());
expressApp.use(bodyParser.urlencoded());

const mvcMiddleware = new MvcMiddleware(expressApp, container);
// ...