MongoDB from Node.js

The official driver

import { MongoClient, ObjectId } from "mongodb";

const client = new MongoClient(process.env.MONGODB_URI);
await client.connect();
const db = client.db("cafe");

export async function getDish(id) {
  return db.collection("dishes").findOne({ _id: new ObjectId(id) });
}

export async function addRating(id, stars) {
  const result = await db.collection("dishes").updateOne(
    { _id: new ObjectId(id) },
    { $push: { ratings: stars } },
  );
  return result.matchedCount === 1;
}

export async function topDishes() {
  return db.collection("dishes").aggregate([
    { $addFields: { avg: { $avg: "$ratings" } } },
    { $sort: { avg: -1 } },
    { $limit: 5 },
  ]).toArray();
}

• Never build filters from raw request bodies — { email: req.body.email } where email is { "$ne": null } matches everyone (NoSQL injection). Validate types first.
• Keep the connection string in an environment variable.
• Mongoose wraps this with schemas and models; Prisma also supports MongoDB.