add comment et modif import dotenv

server/config/db.js

@@ -1,15 +1,15 @@
-const { config } = require("dotenv");
-const mongoose = require("mongoose");
+require("dotenv").config(); // this reads the .env file and sets the environment variables.
+const mongoose = require("mongoose"); // this is the ODM for MongoDB
 
-mongoose
-  .connect(
+mongoose // this connects to the MongoDB database
+  .connect( // the connection string is stored in the .env file
     "mongodb+srv://" +
       process.env.DB_USER_PASS +
-      "@cluster0.v8rv1aj.mongodb.net/khagu-dev?retryWrites=true&w=majority",
+      "@cluster0.v8rv1aj.mongodb.net/khagu-dev?retryWrites=true&w=majority", // this is the connection string
     {
-      useNewUrlParser: true,
-      useUnifiedTopology: true,
+      useNewUrlParser: true, // these are some options to avoid deprecation warnings
+      useUnifiedTopology: true, // these are some options to avoid deprecation warnings
     }
   )
-  .then(() => console.log("connected to MongoDB"))
-  .catch((err) => console.log("Failed to connect to MongoDB :", err));
+  .then(() => console.log("connected to MongoDB")) // if the connection is successful, this message is printed
+  .catch((err) => console.log("Failed to connect to MongoDB :", err)); // if the connection fails, this message is printed