Angular Testing Course

Author: jhades

src/app/model/course.ts

@@ -3,7 +3,7 @@ export interface Course {
   seqNo:number;
   titles: {
     description:string;
-    longDescription: string;
+    longDescription?: string;
   };
   iconUrl: string;
   uploadedImageUrl:string;

src/app/services/courses.service.spec.ts

@@ -0,0 +1,97 @@
+import {TestBed} from '@angular/core/testing';
+import {HttpClientTestingModule, HttpTestingController} from '@angular/common/http/testing';
+import {CoursesService} from './courses.service';
+import {HttpClient, HttpErrorResponse} from '@angular/common/http';
+import {COURSES} from '../../../server/db-data';
+
+
+describe('CoursesService', () => {
+
+  let httpClient: HttpClient;
+  let httpTestingController: HttpTestingController;
+  let coursesService: CoursesService;
+
+  beforeEach(() => {
+
+    TestBed.configureTestingModule({
+      imports: [HttpClientTestingModule],
+      providers: [
+        CoursesService
+      ]
+    });
+
+    httpClient = TestBed.get(HttpClient);
+    httpTestingController = TestBed.get(HttpTestingController);
+    coursesService = TestBed.get(CoursesService);
+
+  });
+
+
+  it('should retrieve all courses', () => {
+
+    coursesService.findAllCourses()
+      .subscribe(courses => {
+
+        expect(<any>courses).toBeTruthy('No value returned');
+        expect(courses.length).toBe(12, `number of courses not correct`);
+
+        const course = courses.find(course => course.id == 12);
+
+        expect(course.titles.description).toBe('Angular Testing Course',
+          `The name of the course is incorrect`);
+
+      });
+
+    const req = httpTestingController.expectOne('/api/courses');
+    expect(req.request.method).toEqual('GET');
+
+    req.flush({payload: Object.values(COURSES)});
+
+  });
+
+
+  it('should save a course', () => {
+
+    coursesService.saveCourse(12, {titles: {description: 'Testing Course'}})
+      .subscribe();
+
+    const req = httpTestingController.expectOne('/api/courses/12');
+    expect(req.request.method).toEqual('PUT');
+
+    req.flush({});
+
+  });
+
+
+  it('should error the returned observable if request fails', () => {
+
+    const errorMessage = 'Internal Server Error';
+
+    coursesService.saveCourse(12, {titles: {description: 'Testing Course'}})
+      .subscribe(() => {
+
+          fail('The returned observable should have errored out.');
+
+        },
+        (error: HttpErrorResponse) => {
+          expect(error.status).toEqual(500, 'status');
+          expect(error.error).toEqual(errorMessage, 'message');
+        }
+      );
+
+
+    const req = httpTestingController.expectOne('/api/courses/12');
+
+    // Respond with mock error
+    req.flush(errorMessage, {status: 500, statusText: 'Error'});
+
+  });
+
+
+  afterEach(() => {
+
+    httpTestingController.verify();
+
+  });
+
+});