feat: add in tests for file uploadn and download

Author: jmcdo29

apps/complex-sample/README.md

@@ -21,7 +21,3 @@ We created our own ParseIntPipe even though Nest provides one just to show how t
 ## Future Additions
 
 Filters can be added in the future to make for even better example of tests.
-
-## Closing Remarks
-
-Do note that while the non-mocked E2E test looks cleaner and easier to deal with, it is also a lot more prone to breaking as it very closely depends on the logic implemented in the CatsService. If that logic changes, the test will fail, while for the most part, the mocked variant will pass. Just as in the unit tests, it is possible to get each provider individually so that you can mock in each function as your heart desires. _(Note to self: I should add that in)_

apps/file-up-and-down-sample/README.md

@@ -0,0 +1,5 @@
+<p align="center">
+  <img src="./testCoverage.png"/>
+</p>
+
+# file-up-and-down-sample

apps/file-up-and-down-sample/jest.config.js

@@ -1,15 +1,5 @@
+const baseConfig = require('../../jest.config');
+
 module.exports = {
-  displayName: 'file-up-and-down-sample',
-  preset: '../../jest.preset.js',
-  globals: {
-    'ts-jest': {
-      tsconfig: '<rootDir>/tsconfig.spec.json',
-    },
-  },
-  testEnvironment: 'node',
-  transform: {
-    '^.+\\.[tj]s$': 'ts-jest',
-  },
-  moduleFileExtensions: ['ts', 'js', 'html'],
-  coverageDirectory: '../../coverage/apps/file-up-and-down-sample',
+  ...baseConfig,
 };

apps/file-up-and-down-sample/src/app/app.controller.spec.ts

@@ -1,24 +1,95 @@
+import { StreamableFile } from '@nestjs/common';
 import { Test, TestingModule } from '@nestjs/testing';
+import { Readable } from 'stream';
 
 import { AppController } from './app.controller';
 import { AppService } from './app.service';
 
 describe('AppController', () => {
   let app: TestingModule;
+  let appController: AppController;
 
   beforeAll(async () => {
     app = await Test.createTestingModule({
       controllers: [AppController],
-      providers: [AppService],
+      providers: [
+        {
+          provide: AppService,
+          useValue: {
+            getData: jest
+              .fn()
+              .mockReturnValue({ message: 'AppService#getData' }),
+            getFileStream: jest.fn().mockImplementation(() => {
+              const readable = new Readable();
+              readable.push(Buffer.from('Hello World!'));
+              readable.push(null);
+              return readable;
+            }),
+          },
+        },
+      ],
     }).compile();
+    appController = app.get<AppController>(AppController);
   });
 
   describe('getData', () => {
     it('should return "Welcome to file-up-and-down-sample!"', () => {
-      const appController = app.get<AppController>(AppController);
       expect(appController.getData()).toEqual({
-        message: 'Welcome to file-up-and-down-sample!',
+        message: 'AppService#getData',
       });
     });
   });
+  describe('postFile', () => {
+    it('should return the file.originalname property', () => {
+      expect(
+        appController.postFile({
+          originalname: 'testfile.json',
+          buffer: Buffer.from('Hello'),
+          destination: '',
+          fieldname: 'file',
+          filename: 'new-file.json',
+          mimetype: 'text/plain',
+          encoding: '7bit',
+          path: '',
+          size: 5091,
+          stream: new Readable(),
+        }),
+      ).toEqual('testfile.json');
+    });
+  });
+  describe('getStreamableFile', () => {
+    it('should return a streamable file', () => {
+      expect(appController.getStreamableFile()).toEqual(
+        new StreamableFile(Buffer.from('Hello World!')),
+      );
+    });
+  });
+  describe('getFileViaResStream', () => {
+    it('should pipe the response object through the readStream', (done) => {
+      // mocking all of the writable methods
+      const resMock: NodeJS.WritableStream = {
+        end: done,
+        write: jest.fn(),
+        addListener: jest.fn(),
+        emit: jest.fn(),
+        eventNames: jest.fn(),
+        getMaxListeners: jest.fn(),
+        listenerCount: jest.fn(),
+        listeners: jest.fn(),
+        off: jest.fn(),
+        on: jest.fn(),
+        once: jest.fn(),
+        prependListener: jest.fn(),
+        prependOnceListener: jest.fn(),
+        rawListeners: jest.fn(),
+        removeAllListeners: jest.fn(),
+        removeListener: jest.fn(),
+        setMaxListeners: jest.fn(),
+        writable: true,
+      };
+      // keep in mind this is the absolute **minimum** for testing, and should be expanded upon with better tests later
+      appController.getFileViaResStream(resMock);
+      expect(resMock.on).toBeCalled();
+    });
+  });
 });

apps/file-up-and-down-sample/src/app/app.controller.ts

@@ -1,4 +1,15 @@
-import { Controller, Get } from '@nestjs/common';
+import {
+  Controller,
+  Get,
+  UploadedFile,
+  Post,
+  StreamableFile,
+  Res,
+  UseInterceptors,
+} from '@nestjs/common';
+import { FileInterceptor } from '@nestjs/platform-express';
+import { Express } from 'express';
+import 'multer';
 
 import { AppService } from './app.service';
 
@@ -10,4 +21,20 @@ export class AppController {
   getData() {
     return this.appService.getData();
   }
+
+  @UseInterceptors(FileInterceptor('file'))
+  @Post('post-file')
+  postFile(@UploadedFile() file: Express.Multer.File) {
+    return file.originalname;
+  }
+
+  @Get('streamable-file')
+  getStreamableFile() {
+    return new StreamableFile(this.appService.getFileStream());
+  }
+
+  // normally, `@Res()` would be a `Response` type, but I'm only interested in piping it here, so this makes the mock in the spec smaller
+  @Get('res-stream') getFileViaResStream(@Res() res: NodeJS.WritableStream) {
+    this.appService.getFileStream().pipe(res);
+  }
 }

apps/file-up-and-down-sample/src/app/app.service.spec.ts

@@ -1,4 +1,6 @@
 import { Test } from '@nestjs/testing';
+import * as fs from 'fs';
+import { join } from 'path';
 
 import { AppService } from './app.service';
 
@@ -19,5 +21,17 @@ describe('AppService', () => {
         message: 'Welcome to file-up-and-down-sample!',
       });
     });
+    describe('getFileStream', () => {
+      it('should get the file information', () => {
+        // this is passing a value to an internal constructor that isn't usually exposed. Only do this if you understand the implications
+        // ref: https://github.com/nodejs/node/blob/master/lib/internal/fs/streams.js#L145
+        const stream = new fs.ReadStream('path' as unknown);
+        const crsMock = jest
+          .spyOn(fs, 'createReadStream')
+          .mockReturnValue(stream);
+        expect(service.getFileStream()).toEqual(stream);
+        expect(crsMock).toBeCalledWith(join(process.cwd(), 'package.json'));
+      });
+    });
   });
 });

apps/file-up-and-down-sample/src/app/app.service.ts

@@ -1,8 +1,14 @@
 import { Injectable } from '@nestjs/common';
+import { createReadStream } from 'fs';
+import { join } from 'path';
 
 @Injectable()
 export class AppService {
   getData(): { message: string } {
     return { message: 'Welcome to file-up-and-down-sample!' };
   }
+
+  getFileStream() {
+    return createReadStream(join(process.cwd(), 'package.json'));
+  }
 }

apps/file-up-and-down-sample/test/app.e2e-spec.ts

@@ -0,0 +1,51 @@
+import { INestApplication } from '@nestjs/common';
+import { Test } from '@nestjs/testing';
+import { readFile } from 'fs/promises';
+import { request, spec } from 'pactum';
+import { join } from 'path/posix';
+
+import { AppModule } from '../src/app/app.module';
+
+describe('File Upload nad Download E2E', () => {
+  let app: INestApplication;
+  beforeAll(async () => {
+    const modRef = await Test.createTestingModule({
+      imports: [AppModule],
+    }).compile();
+    app = modRef.createNestApplication();
+    app.setGlobalPrefix('api');
+    await app.listen(0);
+    const url = await app.getUrl();
+    request.setBaseUrl(`${url.replace('[::1]', 'localhost')}/api`);
+  });
+
+  afterAll(async () => {
+    await app.close();
+  });
+
+  describe('AppController', () => {
+    let fileContents: string;
+    beforeAll(async () => {
+      fileContents = (
+        await readFile(join(process.cwd(), 'package.json'))
+      ).toString();
+    });
+    it('GET /', async () => {
+      return spec()
+        .get('/')
+        .expectBody({ message: 'Welcome to file-up-and-down-sample!' });
+    });
+    it('POST /post-file', async () => {
+      return spec()
+        .post('/post-file')
+        .withFile('file', join(process.cwd(), 'package.json'))
+        .expectBody('package.json');
+    });
+    it('GET /streamable-file', async () => {
+      return spec().get('/streamable-file').expectBody(fileContents);
+    });
+    it('GET /res-stream', async () => {
+      return spec().get('/res-stream').expectBody(fileContents);
+    });
+  });
+});

apps/file-up-and-down-sample/test/jest-e2e.js

@@ -0,0 +1,6 @@
+
+const e2eBaseConfig = require('../../../jest.e2e');
+
+module.exports = {
+  ...e2eBaseConfig,
+};