Save Courses and Failed Http Reqeust

New test cases for saving a course successfully and when a http request fails

Author: tpersaud27

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

@@ -5,6 +5,8 @@ import {
   HttpTestingController,
 } from "@angular/common/http/testing";
 import { COURSES } from "../../../../server/db-data";
+import { Course } from "../model/course";
+import { HttpErrorResponse } from "@angular/common/http";
 
 describe("CoursesService", () => {
   let coursesService: CoursesService;
@@ -39,8 +41,86 @@ describe("CoursesService", () => {
     // We expect the request to be a GET request
     expect(request.request.method).toEqual("GET");
 
+    // Execute the http request
     // We should specify which data should be returned
     // This is some test data
     request.flush({ payload: Object.values(COURSES) });
   });
+
+  it("should return course based on id", () => {
+    coursesService.findCourseById(12).subscribe({
+      next: (course) => {
+        // First we expect to get some data back
+        expect(course).toBeTruthy("No courses returned");
+        // Check the id of the course returned
+        expect(course.id).toBe(12);
+      },
+    });
+    // We expect one request to be sent at this endpoint
+    const request = httpTestingController.expectOne("/api/courses/12");
+    // We expect the request to be a GET request
+    expect(request.request.method).toEqual("GET");
+    // We pass some test data to the request to trigger the request
+    request.flush(COURSES[12]);
+  });
+
+  it("should save course data successfully", () => {
+    const changes: Partial<Course> = {
+      titles: { description: "Testing Course" },
+    };
+
+    coursesService.saveCourse(12, changes).subscribe({
+      next: (course) => {
+        expect(course.id).toBe(12);
+      },
+    });
+    // This will create a http put request
+    const request = httpTestingController.expectOne("/api/courses/12");
+    // validate the type of request
+    expect(request.request.method).toEqual("PUT");
+    // Here we are validating the body of the put request sent to the server
+    // Check if the data being passed to the endpoint is the data we specified
+    expect(request.request.body.titles.description).toBe(
+      changes.titles.description
+    );
+
+    // This triggers the mock request
+    // The data we passed to the request it the mock data
+    // Note the data is the course data with the new changes added
+    request.flush({ ...COURSES[12], ...changes });
+  });
+
+  it("should give error if save course fails", () => {
+    const changes: Partial<Course> = {
+      titles: { description: "Testing Course" },
+    };
+
+    coursesService.saveCourse(12, changes).subscribe({
+      next: () => {
+        fail("save course operation should have failed");
+      },
+      error: (error: HttpErrorResponse) => {
+        expect(error.status).toBe(500);
+      },
+    });
+
+    // Now we trigger the http request
+    const request = httpTestingController.expectOne("/api/courses/12");
+    expect(request.request.method).toEqual("PUT");
+
+    request.flush("Save course failed", {
+      status: 500,
+      statusText: "Internal Server Error",
+    });
+  });
+
+
+  
+
+  // After each test this will be executed
+  afterEach(() => {
+    // verify there are no more requests
+    // We want to make sure no other requests are being triggered
+    httpTestingController.verify();
+  });
 });