express-bed

Angular style TestBed for Express apps.

This is a minimal implementation of a TestBe for typescript Express routes, in the style of Angular.

It allows for easy instantiation of routes for testing, along with convenience methods for passing in mocks and stubs, as well as getting easy access to injected code for spying in tests.

It relies on each of the routes being classes, with a public create method, which is passed an express app and calls app.get etc. as shown in the usage examples.

Installation

npm install express-bed

Usage (examples from unit tests of project)

To import the package:

import { BaseRoute, ExpressBed, ExpressTestBed } from 'express-bed';
 
const expressBed = ExpressBed.configureTestingModule({
  routes: [
    //routes
  ],
  injectables: [
    //injectables
  ]
});

Usage examples as per the package unit tests:

import { Express, Request, Response } from 'express';
import { BaseRoute, ExpressBed, ExpressTestBed } from './express-bed';
import supertest = require('supertest');
 
describe('express-bed', () => {
  let testBed: ExpressTestBed;
 
  describe('configureTestingModule', () => {
    it('should return a ExpressTestBed object with the correct routes ' +
    'if they are passed via config', (done: any) => {
      class TestRoute implements BaseRoute {
        public create(app: Express) {
          app.get('/user/validPath/', (req: Request, res: Response) => {
            res.status(200).send();
          });
        }
      }
 
      testBed = ExpressBed.configureTestingModule({
        routes: [TestRoute]
      });
 
      try {
        supertest(testBed.app)
          .get('/user/validPath/')
          .expect(200)
          .then(() => done());
      } catch (error) {
        fail();
      }
 
      try {
        supertest(testBed.app)
          .get('/user/invalidPath/')
          .expect(404)
          .then(() => done());
      } catch (error) {
        fail();
      }
    });
 
    it('should return a ExpressTestBed object with the correct routes and injectables, ' + 
    'as well as any injectable dependencies if they are passed via config', (done: any) => {
      class Dependency {
        public doDepStuff(): string {
          return 'blah';
        }
      }
 
      class TestInjectable {
        constructor(private dep: Dependency) {}
 
        public doSomething() {
          this.dep.doDepStuff();
        }
      }
 
      class TestInjectable2 {
        public doSomethingElse() {
          console.log('blah');
        }
      }
 
      class TestRoute implements BaseRoute {
        constructor(
          private testInjectable: TestInjectable,
          private testInjectable2: TestInjectable2
        ) {
          this.testInjectable.doSomething();
          this.testInjectable2.doSomethingElse();
        }
 
        public create(app: Express) {
          app.get('/user/validPath/', (req: Request, res: Response) => {
            res.status(200).send();
          });
        }
      }
 
      testBed = ExpressBed.configureTestingModule({
        routes: [TestRoute],
        injectables: [
          {
            inject: TestInjectable,
            injectables: [Dependency]
          },
          TestInjectable2
        ]
      });
 
      try {
        supertest(testBed.app)
          .get('/user/validPath/')
          .expect(200)
          .then(() => done());
      } catch (error) {
        fail();
      }
 
      expect(testBed.get(TestInjectable) instanceof TestInjectable).toBe(true);
      expect(testBed.get(TestInjectable2) instanceof TestInjectable2).toBe(
        true
      );
    });
 
    it('should return a ExpressTestBed object with the correct routes and ' + 
    'injectables if they are passed via config', (done: any) => {
      class TestInjectable {
        public doSomething() {}
      }
 
      class TestRoute implements BaseRoute {
        constructor(private testInjectable: TestInjectable) {
          this.testInjectable.doSomething();
        }
 
        public create(app: Express) {
          app.get('/user/validPath/', (req: Request, res: Response) => {
            res.status(200).send();
          });
        }
      }
 
      testBed = ExpressBed.configureTestingModule({
        routes: [TestRoute],
        injectables: [TestInjectable]
      });
 
      try {
        supertest(testBed.app)
          .get('/user/validPath/')
          .expect(200)
          .then(() => done());
      } catch (error) {
        fail();
      }
 
      expect(testBed.get(TestInjectable) instanceof TestInjectable).toBe(true);
    });
 
    it('should return a ExpressTestBed object with the correct routes if ' + 
    'multiple routes provided', (done: any) => {
      class TestRoute implements BaseRoute {
        public create(app: Express) {
          app.get('/user/validPath/', (req: Request, res: Response) => {
            res.status(200).send();
          });
        }
      }
 
      class TestRoute2 implements BaseRoute {
        public create(app: Express) {
          app.post('/user/validPath2/', (req: Request, res: Response) => {
            res.status(200).send();
          });
        }
      }
 
      testBed = ExpressBed.configureTestingModule({
        routes: [TestRoute, TestRoute2]
      });
 
      try {
        supertest(testBed.app)
          .get('/user/validPath/')
          .expect(200)
          .then(() => done());
      } catch (error) {
        fail();
      }
 
      try {
        supertest(testBed.app)
          .post('/user/validPath2/')
          .expect(200)
          .then(() => done());
      } catch (error) {
        fail();
      }
    });
  });
});