ts-express-framework

An opinionated TypeScript framework for quickly bootstrapping REST APIs in NodeJS/TypeScript/Express.

How is it opinionated?

• Designed for Typescript
• Uses decorators to define controllers and routes
• Controllers are classes, methods are routes
• Controllers must have a constructor that does not take any arguments

Features

• Role-based access control
• Easy integration with any authentication framework that uses standard Express middleware
• Swagger documentation generation

Installation

npm install -S @lreading/ts-express-framework

Basic Usage

Controller & Route:

import { Controller, Get } from '@lreading/ts-express-framework';

@Controller('/hello')
export class HelloController {
  @Get('/', {
    summary: 'Hello, World!', // Swagger doc, optional
    description: 'A simple hello world route.', // Swagger doc, optional
    exampleResponse: 'Hello, World!', // Swagger doc, optional
    allowAnonymous: true, // Allow unauthenticated users to access this route
})
  async helloWorld(req, res) {
    // Return whatever type/object you want.
    // This will be wrapped into a response object:
    // { <your return value> }
    return 'Hello, World!';
  }

  @Post('/some-data', {
    summary: 'Posts some data',
    allowAnonymous: false,
    description: 'Creates the some data entity or something',
    bodyDefinition: { // Swagger doc, optional
      description: 'The data to post', // Swagger doc, optional
      required: true, // Swagger doc, optional
      example: { foo: 'bar' } // Swagger doc, optional
    },
    // Or, for query parameters:
    // params: [ // Swagger doc, optional
    //   {
    //      name: string;
    //      in: 'query' | 'path';
    //      required: boolean;
    //      type: 'boolean' | 'object' | 'number' | 'string' | 'integer';
    //      description?: string;
    //   }
    // ],
    exampleResponse: { // Swagger doc, optional
      foo: 'bar'
    },
    allowedRoles: ['admin'] // Only use if you've mapped the req.user.roleNames, see auth middleware section
  })
  asyn postData(req, res) {
    // Do something with the data
    return { foo: 'bar' };
  }
}

Server:

import express from 'express';
import { registerControllers } from '@lreading/ts-express-framework';

import { HelloController } from './controllers/hello.controller';

const app = express();

registerControllers({
  app, // The express app

  // Array of controllers to register
  controllers: [HelloController],

  // Optional - location to save the swagger doc 
  swaggerDocLocation: 'swagger.json',

  // Optional - middleware to run for authorization.
  // See the note on authorization middleware if you intend to use RBAC
  authMiddleware: authMiddleware as any
});

app.listen(3000, () => {
  console.log('Server started on port 3000');
});

Auth Middleware

This framework expects the auth middleware to create a User object on the request. This object should have a roleNames property that is an array of strings. This is used for role-based access control. If you do not specify roles in your controller annotations, it will only do authentication, not authorization.

For more information on the user object, see the User interface.

Api Response / Errors

There is an ApiResponse wrapper that will take generate the status code and wrap whatever you're returning into the body of the request, such as this:

{
    <your return value>
}

There are multiple API errors that map to common HTTP status codes. You can use these to return errors in your controllers. For example:

import { BadRequestError } from '@lreading/ts-express-framework';

@Get('/some-route/{id}', {
  params: [{
    name: 'id',
    in: 'path',
    required: true,
    type: 'number',
    description: 'The ID of the thing'
  }]
})
async getSomeData(req, res) {
  if (!req.params.id) {
    throw new BadRequestError('ID is required');
  }
  // ... etc
}