Mongodb setup bug + tests

src/setup/MongoDB.ts

@@ -8,23 +8,15 @@ import { MongoClient } from "mongodb";
  * @returns The function `checkExistingMongoDB` returns a promise that resolves to a string or null.
  */
 export async function checkExistingMongoDB(): Promise<string | null> {
-  const existingMongoDbUrls = [
-    process.env.MONGO_DB_URL,
-    "mongodb://localhost:27017",
-  ];
+  const existingMongoDbUrls = process.env.MONGO_DB_URL;
 
-  for (const url of existingMongoDbUrls) {
-    if (!url) {
-      continue;
-    }
-
-    const isConnected = await checkConnection(url);
-    if (isConnected) {
-      return url;
-    }
+  if (!existingMongoDbUrls) {
+    return null;
   }
-
-  return null;
+  const isConnected = await checkConnection(existingMongoDbUrls);
+  if (isConnected) {
+    return existingMongoDbUrls;
+  } else return null;
 }
 
 // Check the connection to MongoDB with the specified URL.
@@ -54,6 +46,7 @@ export async function checkConnection(url: string): Promise<boolean> {
       );
     } else {
       console.log(`\nConnection to MongoDB failed. Please try again.\n`);
+      console.log(error);
     }
     return false;
   }
@@ -71,7 +64,7 @@ export async function askForMongoDBUrl(): Promise<string> {
       type: "input",
       name: "url",
       message: "Enter your MongoDB URL:",
-      default: process.env.MONGO_DB_URL,
+      default: "mongodb://localhost:27017",
     },
   ]);
 

tests/setup/checkExistingMongoDB.spec.ts

@@ -1,8 +1,66 @@
-import { expect, it, describe } from "vitest";
-import { checkExistingMongoDB } from "../../src/setup/MongoDB";
+import { expect, it, describe, vi, afterEach } from "vitest";
+import { checkConnection, checkExistingMongoDB } from "../../src/setup/MongoDB";
+import { MongoClient } from "mongodb";
 
 describe("Setup -> checkExistingMongoDB", () => {
+  afterEach(() => {
+    // Clear all mocks after each test
+    vi.restoreAllMocks();
+  });
+  it("should return the first valid URL when a connection is found", async () => {
+    const result = await checkExistingMongoDB();
+    expect(result).toBe(process.env.MONGO_DB_URL);
+  });
+
+  it("should return null if MONGO_DB_URL is not set", async () => {
+    process.env.MONGO_DB_URL = "";
+    const result = await checkExistingMongoDB();
+    expect(result).toBeNull();
+  });
+
+  it("should return null if checkConnection returns false", async () => {
+    // Set the environment variable
+    process.env.MONGO_DB_URL = "mongodb://testUrl";
+
+    // Spy on the checkConnection function to return false
+    vi.spyOn(MongoClient, "connect").mockImplementation(() => {
+      throw new Error("Test error");
+    });
+
+    // Call the function
+    const result = await checkExistingMongoDB();
+
+    // Check that the result is null
+    expect(result).toBeNull();
+  });
+
+  it("should return false and log error when connection fails", async () => {
+    // Spy on the MongoClient.connect function to throw an error
+    vi.spyOn(MongoClient, "connect").mockImplementation(() => {
+      throw new Error("Test error");
+    });
+
+    // Call the function with a test URL
+    const result = await checkConnection("mongodb://testUrl");
+
+    // Check that the result is false
+    expect(result).toBe(false);
+  });
+
+  it("should return false and log error when connection fails with unknown error type", async () => {
+    // Spy on the MongoClient.connect function to throw an Non-Error
+    vi.spyOn(MongoClient, "connect").mockImplementation(() => {
+      throw "Test error";
+    });
+
+    // Call the function with a test URL
+    const result = await checkConnection("mongodb://testUrl");
+
+    // Check that the result is false
+    expect(result).toBe(false);
+  });
   it("should return the first valid URL when a connection is found", async () => {
+    process.env.MONGO_DB_URL = "mongodb://localhost:27017/talawa-api";
     const result = await checkExistingMongoDB();
     expect(result).toBe(process.env.MONGO_DB_URL);
   });