services testing complete

Author: max-in-bc

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

@@ -0,0 +1,35 @@
+import {CalculatorService} from './calculator.service';
+import {LoggerService} from './logger.service';
+import {TestBed} from '@angular/core/testing';
+
+describe('CalculatorService', () => {
+  let calculator: CalculatorService;
+  let loggerSpy: any;
+  beforeEach(() => {
+    console.log('Calling beforeEach');
+    loggerSpy = jasmine.createSpyObj('LoggerService', ['log']);
+
+    TestBed.configureTestingModule({
+      providers: [
+        CalculatorService,
+        { provide: LoggerService, useValue: loggerSpy }
+      ]
+    });
+
+    calculator = TestBed.get(CalculatorService); // simulate angular DI
+  });
+
+  it ('should add two numbers', () => {
+    console.log('add test');
+    const result = calculator.add(2, 2);
+    expect(result).toBe(4);
+    expect(loggerSpy.log).toHaveBeenCalledTimes(1);
+
+  });
+  it ('should subtract two numbers', () => {
+    console.log('subtract test');
+    const result = calculator.subtract(2, 2);
+    expect(result).toBe(0, 'unexpected subtraction result');
+    expect(loggerSpy.log).toHaveBeenCalledTimes(1);
+  });
+});

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

@@ -12,13 +12,13 @@ export class CalculatorService {
 
   }
 
-  add(n1: number, n2:number) {
-    this.logger.log("Addition operation called");
+  add(n1: number, n2: number) {
+    this.logger.log('Addition operation called');
     return n1 + n2;
   }
 
-  subtract(n1: number, n2:number) {
-    this.logger.log("Subtraction operation called");
+  subtract(n1: number, n2: number) {
+    this.logger.log('Subtraction operation called');
     return n1 - n2;
   }
 

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

@@ -0,0 +1,114 @@
+import {CoursesService} from './courses.service';
+import {TestBed} from '@angular/core/testing';
+import {HttpClientTestingModule, HttpTestingController} from '@angular/common/http/testing';
+import {COURSES, findLessonsForCourse} from '../../../../server/db-data';
+import {Course} from '../model/course';
+import {HttpErrorResponse} from '@angular/common/http';
+
+describe('CoursesService', () => {
+  let coursesService: CoursesService;
+  let httpTestingController: HttpTestingController;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      imports: [
+        HttpClientTestingModule
+      ],
+      providers: [
+        CoursesService,
+      ]
+    });
+
+    coursesService = TestBed.get(CoursesService);
+    httpTestingController = TestBed.get(HttpTestingController);
+  });
+  it('should retrieve all courses', () => {
+    coursesService.findAllCourses()
+      .subscribe(courses => {
+        expect(courses).toBeTruthy('no courses returned');
+        expect(courses.length).toBe(12, 'incorrect number of courses');
+
+        const course = courses.find(course => course.id == 12);
+
+        expect(course.titles.description).toBe('Angular Testing Course');
+      });
+
+    const req = httpTestingController.expectOne('/api/courses');
+    expect(req.request.method).toEqual('GET');
+    req.flush({
+      payload: Object.values(COURSES)
+    });
+
+  });
+  it('should find a course by id', () => {
+    coursesService.findCourseById(12)
+      .subscribe(course => {
+        expect(course).toBeTruthy('no course returned');
+        expect(course.id).toBe(12, 'incorrect course id');
+      });
+
+    const req = httpTestingController.expectOne('/api/courses/12');
+    expect(req.request.method).toEqual('GET');
+    req.flush(COURSES[12]);
+  });
+
+  it('should save the course data', () => {
+    const changes: Partial<Course> = {
+      titles: {description: 'Testing Course'}
+    };
+    coursesService.saveCourse(12, changes).subscribe(course => {
+      expect(course.id).toBe(12);
+    });
+
+    const req = httpTestingController.expectOne('/api/courses/12');
+    expect(req.request.method).toEqual('PUT');
+    expect(req.request.body.titles).toEqual(changes.titles);
+
+    req.flush({
+      ...COURSES[12],
+      ...changes
+    });
+
+  });
+
+  it('should give an error if save course fails', () => {
+    const changes: Partial<Course> = {
+      titles: {description: 'Testing Course'}
+    };
+    coursesService.saveCourse(12, changes)
+      .subscribe(() => fail('the save course op should have failed'),
+      (error: HttpErrorResponse) => {
+        expect(error.status).toBe(500);
+      }
+    );
+
+    const req = httpTestingController.expectOne('/api/courses/12');
+    expect(req.request.method).toEqual('PUT');
+    req.flush('Save course failed', {status: 500, statusText: 'Internal Server Error'});
+
+  });
+
+  it('should find a list of lessons', () => {
+    coursesService.findLessons(12)
+      .subscribe(lessons => {
+        expect(lessons).toBeTruthy();
+        expect(lessons.length).toBe(3);
+
+      });
+
+    const req = httpTestingController.expectOne(request => request.url === '/api/lessons');
+    expect(req.request.method).toEqual('GET');
+    expect(req.request.params.get('courseId')).toEqual('12');
+    expect(req.request.params.get('filter')).toEqual('');
+    expect(req.request.params.get('sortOrder')).toEqual('asc');
+    expect(req.request.params.get('pageNumber')).toEqual('0');
+    expect(req.request.params.get('pageSize')).toEqual('3');
+    req.flush({
+      payload: findLessonsForCourse(12).slice(0, 3)
+    });
+  });
+
+  afterEach(() => {
+    httpTestingController.verify();
+  });
+});

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

@@ -1,17 +1,17 @@
 
 
-import {Injectable} from "@angular/core";
-import {HttpClient, HttpParams} from "@angular/common/http";
-import {Observable} from "rxjs";
-import {Course} from "../model/course";
-import {map} from "rxjs/operators";
-import {Lesson} from "../model/lesson";
+import {Injectable} from '@angular/core';
+import {HttpClient, HttpParams} from '@angular/common/http';
+import {Observable} from 'rxjs';
+import {Course} from '../model/course';
+import {map} from 'rxjs/operators';
+import {Lesson} from '../model/lesson';
 
 
 @Injectable()
 export class CoursesService {
 
-    constructor(private http:HttpClient) {
+    constructor(private http: HttpClient) {
 
     }
 
@@ -27,12 +27,12 @@ export class CoursesService {
     }
 
 
-    saveCourse(courseId:number, changes: Partial<Course>): Observable<Course> {
+    saveCourse(courseId: number, changes: Partial<Course>): Observable<Course> {
         return this.http.put<Course>(`/api/courses/${courseId}`, changes);
     }
 
     findLessons(
-        courseId:number, filter = '', sortOrder = 'asc',
+        courseId: number, filter = '', sortOrder = 'asc',
         pageNumber = 0, pageSize = 3):  Observable<Lesson[]> {
 
         return this.http.get('/api/lessons', {
@@ -43,7 +43,7 @@ export class CoursesService {
                 .set('pageNumber', pageNumber.toString())
                 .set('pageSize', pageSize.toString())
         }).pipe(
-            map(res =>  res["payload"])
+            map(res =>  res['payload'])
         );
     }