Node.js app cannot connect to MongoDB Atlas cluster - node.js

Question

error:
server running in development mode on port 5000
errorMongoParseError: option usecreateindex is not supported
[nodemon] app crashed - waiting for file changes before starting...
db.js
const connectDB = async () => {
try {
const conn = await mongoose.connect(process.env.MONGO_URI, {
useUnifiedTopology: true,
useNewUrlParser: true,
useCreateIndex: true,
});
console.log(`MongoDB connected :${conn.connection.host}`);
} catch (error) {
console.error(`error${error}`);
process.exit(1);
}
};
export default connectDB;
server.js
import express from "express";
import dotenv from "dotenv";
import connectDB from './config/db.js'
import products from './data/products.js'
dotenv.config();
connectDB()
const app = express();
app.get("/", (req, res) => {
res.send("api is running... ");
});
app.get("/api/products", (req, res) => {
res.json(products);
});
app.get("/api/products/:id", (req, res) => {
const product = products.find(p => p._id === req.params.id);
res.json(product);
});
const PORT = process.env.PORT || 5000
app.listen(PORT, console.log(`server running in ${process.env.NODE_ENV} mode on port ${PORT}`));

Answer 1

No More Deprecation Warning Options
Mongoose docs
useNewUrlParser, useUnifiedTopology, useFindAndModify, and
useCreateIndex are no longer supported options. Mongoose 6 always
behaves as if useNewUrlParser, useUnifiedTopology, and useCreateIndex
are true, and useFindAndModify is false. Please remove these options
from your code.
db.js
const connectDB = async () => {
try {
const conn = await mongoose.connect(process.env.MONGO_URI, {
// useUnifiedTopology: true, <-- no longer necessary
// useNewUrlParser: true, <-- no longer necessary
// useCreateIndex: true, <-- no longer necessary
});
console.log(`MongoDB connected :${conn.connection.host}`);
} catch (error) {
console.error(`error${error}`);
process.exit(1);
}
};
export default connectDB;