added normal scenerio test for pet

Author: phshafi

__test__/pet.test.js

@@ -0,0 +1,36 @@
+const app = require("../app");
+const request = require("supertest");
+
+describe("Pet Service", () => {
+    describe("Normal scenario", () => {
+        it("should save the pet in the database", async () => {
+            const response = await request(app).post("/api/pet").send({
+                id: 5,
+                name: "Sandy",
+                type: "Hamster"
+            });
+
+            expect(response.headers["content-type"]).toEqual(expect.stringContaining("application/json"));
+        });
+
+        it("should response with 201 when new pet created with all the fields", async () => {
+            const response = await request(app).post("/api/pet").send({
+                id: 5,
+                name: "Sandy",
+                type: "Hamster"
+            });
+
+            expect(response.statusCode).toBe(201);
+        });
+
+        it("should be content type of json in the header when a new pet is added", async () => {
+            const response = await request(app).post("/api/pet").send({
+                id: 5,
+                name: "Sandy",
+                type: "Hamster"
+            });
+
+            expect(response.headers["content-type"]).toEqual(expect.stringContaining("application/json"));
+        });
+    });
+});