MongoDB integration with Next.js 14

db.js

import { MongoClient } from "mongodb"

let client
let clientPromise

if (!process.env.CONNECTIONSTRING) {
  throw new Error("Please add your MongoDB URI to the .env file")
}

const uri = process.env.CONNECTIONSTRING
const options = {}

if (process.env.NODE_ENV === "development") {
  // In development mode, use a global variable so that the MongoClient instance is not recreated.
  if (!global._mongoClientPromise) {
    client = new MongoClient(uri, options)
    global._mongoClientPromise = client.connect()
  }
  clientPromise = global._mongoClientPromise
} else {
  // In production mode, it's best to not use a global variable.
  client = new MongoClient(uri, options)
  clientPromise = client.connect()
}

async function getDatabase() {
  const client = await clientPromise
  return client.db()
}

export async function getCollection(collectionName) {
  const db = await getDatabase()
  return db.collection(collectionName)
}

export default getDatabase