MongoDB Atlas Documentation

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### Complete replaceOne() Example with Setup

Source: https://www.mongodb.com/docs/drivers/node/current/crud/update/replace

A full Node.js file demonstrating `replaceOne`. It includes connection setup, query definition, the replacement document, execution, and result logging. Ensure you replace the connection string and have the 'sample_mflix' database with 'movies' collection loaded.

```javascript
import { MongoClient } from "mongodb";

// Replace the uri string with your MongoDB deployment's connection string.
const uri = "<connection string uri>";

const client = new MongoClient(uri);

async function run() {
  try {
    
    // Get the database and collection on which to run the operation
    const database = client.db("sample_mflix");
    const movies = database.collection("movies");

    // Create a query for documents where the title contains "The Cat from"
    const query = { title: { $regex: "The Cat from" } };
    
    // Create the document that will replace the existing document
    const replacement = {
      title: `The Cat from Sector ${Math.floor(Math.random() * 1000) + 1}`,
    };

    // Execute the replace operation
    const result = await movies.replaceOne(query, replacement);
    
    // Print the result 
    console.log(`Modified ${result.modifiedCount} document(s)`);
  } finally {
    await client.close();
  }
}
run().catch(console.dir);
```

--------------------------------

### Clone and Setup Node.js MongoDB Driver

Source: https://www.mongodb.com/docs/drivers/node/current/issues-and-help

Clone the driver repository, navigate to the directory, install dependencies, and create a new branch for development.

```bash
git clone https://github.com/mongodb/node-mongodb-native.git
cd node-mongodb-native
npm install
git checkout -b myNewFeature
```

--------------------------------

### Initialize Project and Install Dependencies

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/mongoose/mongoose-get-started

Initializes a new Node.js project and installs Mongoose and Nodemon. Use this to set up your project environment.

```bash
mkdir mongodb-mongoose
cd mongodb-mongoose
npm init -y
npm i mongoose
npm i -D nodemon
```

--------------------------------

### Start Next.js Development Server

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/next-vercel

Run this command to start the local development server for your Next.js application.

```bash
npm run dev
```

--------------------------------

### Install Snappy Dependency

Source: https://www.mongodb.com/docs/drivers/node/current/connect/connection-options/network-compression

Install the Snappy compression algorithm dependency using npm.

```bash
npm install --save snappy
```

--------------------------------

### Install npm Dependencies

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/next-vercel

Install all necessary Node.js dependencies for your Next.js project.

```bash
npm install
```

--------------------------------

### Initialize Project and Install Dependencies

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/mongoose/mongoose-qe

Sets up a new Node.js project, configures it to use ES modules, and installs Mongoose, the MongoDB driver, dotenv, and mongodb-client-encryption.

```bash
mkdir mongoose-qe-app
cd mongoose-qe-app
npm init -y
npm pkg set main="queryable-encryption-tutorial.js"
npm pkg set type="module"
npm pkg set scripts.start="node queryable-encryption-tutorial.js"
npm i mongoose mongodb dotenv mongodb-client-encryption
```

--------------------------------

### Install Zstandard Dependency

Source: https://www.mongodb.com/docs/drivers/node/current/connect/connection-options/network-compression

Install the Zstandard compression algorithm dependency using npm.

```bash
npm install --save @mongodb-js/zstd
```

--------------------------------

### Output of findOne Example

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/retrieve

This is the expected output when running the TypeScript `findOne` example.

```javascript
{ title: 'The Room', imdb: { rating: 3.5, votes: 25673, id: 368226 } }
```

--------------------------------

### updateOne() Example in TypeScript

Source: https://www.mongodb.com/docs/drivers/node/current/crud/update/modify

This TypeScript example demonstrates updating a single document using `updateOne()`. It includes defining an interface for the document structure and utilizes the `upsert: true` option. Proper connection setup and driver installation are required.

```typescript
// Update a document

import { MongoClient } from "mongodb";

// Replace the uri string with your MongoDB deployment's connection string
const uri = "<connection string uri>";

const client = new MongoClient(uri);

// Define the Movie interface
interface Movie {
  plot: string;
  title: string;
}

async function run() {
  try {
    const database = client.db("sample_mflix");
    const movies = database.collection<Movie>("movies");

    /* Update a document that has the title "Random Harvest" to have a
    plot field with the specified value */
    const result = await movies.updateOne(
      { title: "Random Harvest" },
      {
        $set: {
          plot: `A harvest of random numbers, such as: ${Math.random()}`,
        },
      },
      /* Set the upsert option to insert a document if no documents
      match the filter */
      { upsert: true }
    );

    // Print the number of matching and modified documents
    console.log(
      `${result.matchedCount} document(s) matched the filter, updated ${result.modifiedCount} document(s)`
    );
  } finally {
    // Close the connection after the operation completes
    await client.close();
  }
}
// Run the program and print any thrown errors
run().catch(console.dir);

```

--------------------------------

### Install Project Dependencies

Source: https://www.mongodb.com/docs/drivers/node/current/connect/multiple-connections

Install Express.js for the web framework and Mongoose for MongoDB object modeling. These are the core dependencies for this tutorial.

```bash
npm install express mongoose
```

--------------------------------

### ConnectionCheckOutStartedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionCheckOutStarted event. This event indicates that an operation is attempting to acquire a connection from the pool.

```javascript
ConnectionCheckOutStartedEvent {
  time: 2023-02-13T15:56:38.291Z,
  address: '...'
}
```

--------------------------------

### Example Output

Source: https://www.mongodb.com/docs/drivers/node/current/crud/update/modify

This shows the expected console output after successfully updating documents.

```none
Updated 477 documents

```

--------------------------------

### Install AWS SDK Credential Providers

Source: https://www.mongodb.com/docs/drivers/node/current/security/authentication/aws-iam

Install the necessary AWS SDK package for credential providers using npm.

```bash
npm install @aws-sdk/credential-providers
```

--------------------------------

### ServerHeartbeatStartedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

This event indicates that a server heartbeat has started. It includes the connection ID of the server being monitored.

```javascript
ServerHeartbeatStartedEvent {
  connectionId: 'localhost:27017'
}
```

--------------------------------

### Install Dependencies and Generate Prisma Schema

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/prisma

Install project dependencies and generate the Prisma client based on your schema configuration. Re-run `npx prisma generate` if you make further schema changes.

```shell
npm install
npx prisma generate
```

--------------------------------

### ConnectionReadyEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionReady event. This event confirms that a connection has completed its handshake and is ready for operations.

```javascript
ConnectionReadyEvent {
  time: 2023-02-13T15:56:38.291Z,
  address: '...',
  connectionId: 1,
  durationMS: 60
}
```

--------------------------------

### Create a Vector Search Index

Source: https://www.mongodb.com/docs/drivers/node/current/reference/release-notes

Specify the type of a search index when creating it. This example demonstrates creating a vector search index. This feature is available starting from driver version 6.6.

```javascript
const indexName = await collection.createSearchIndex({
    name: 'my-vector-search-index',
    type: 'vectorSearch',
    definition: {
        mappings: { dynamic: false }
    }
});
```

--------------------------------

### ConnectionPoolReadyEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionPoolReady event. This event indicates that a connection pool has successfully initialized and is ready for use.

```javascript
ConnectionPoolReadyEvent {
  time: 2023-02-13T15:56:38.440Z,
  address: '...'
}
```

--------------------------------

### Configure MongoDB Connection URI

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/next-vercel

Rename the example environment file and set your MongoDB connection string as the value for MONGODB_URI.

```none
MONGODB_URI=<Your connection string>
```

--------------------------------

### Example Change Event Output

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/change-streams

This is an example of the output you might see in your terminal when a document is inserted into the 'haikus' collection while the change stream is active.

```none
Received change:
{
  _id: {
    _data: '...'
  },
  operationType: 'insert',
  clusterTime: new Timestamp({ t: 1675800603, i: 31 }),
  fullDocument: {
    _id: new ObjectId("..."),
    ...
  },
  ns: { db: 'insertDB', coll: 'haikus' },
  documentKey: { _id: new ObjectId("...") }
}

```

--------------------------------

### Sample Order with Sufficient Inventory

Source: https://www.mongodb.com/docs/drivers/node/current/crud/transactions/transaction-conv

An example order that can be successfully processed due to sufficient inventory.

```javascript
{ item: "sunblock", qty: 3 },
{ item: "beach chair", qty: 1 }
```

--------------------------------

### Build and Start Next.js Application

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/next-vercel

Commands to build your Next.js application for production and start the production server. This ensures getStaticProps runs at build time, not on every request.

```bash
npm run build
npm run start
```

--------------------------------

### ConnectionCheckedInEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionCheckedIn event. This event is emitted when a connection is returned to the pool after an operation.

```javascript
ConnectionCheckedInEvent {
  time: 2023-02-13T15:54:07.189Z,
  address: '...',
  connectionId: 1
}
```

--------------------------------

### Example Query Output

Source: https://www.mongodb.com/docs/drivers/node/current/get-started

This is an example of the output you can expect after successfully running the Node.js application and querying for the 'Back to the Future' movie.

```json
{
  _id: ...,
  plot: 'A young man is accidentally sent 30 years into the past...',
  genres: [ 'Adventure', 'Comedy', 'Sci-Fi' ],
  ...,
  title: 'Back to the Future',
  ...
}

```

--------------------------------

### Example Application Output

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/mongoose/mongoose-qe

This is an example of the expected output when the Mongoose application successfully inserts and queries encrypted data.

```javascript
Successfully inserted the patient document.
Document ID: new ObjectId('...')
Found patient:
{
   patientRecord: {
      billing: { type: 'Visa', number: '4111111111111111' },
      ssn: '987-65-4320',
      billAmount: 1500
   },
   _id: new ObjectId('...'),
   patientName: 'Jon Doe',
   patientId: 12345678,
   __v: 0,
   __safeContent__: [
      Binary.createFromBase64('EGzhQwBpf1B6W9udskSxJ8kwEEnF5P+SJPZ6ygQ9Ft8=', 0)
   ]
}
Connection closed.
```

--------------------------------

### ConnectionCheckOutFailedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionCheckOutFailed event. This event is emitted when an operation fails to acquire a connection.

```javascript
ConnectionCheckOutFailedEvent {
  time: 2023-02-13T15:56:38.291Z,
  address: '...',
  reason: '...',
  durationMS: 60
}
```

--------------------------------

### ServerOpeningEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

This event signals that a server is opening. It contains the topology ID and the address of the server.

```javascript
ServerOpeningEvent {
  topologyId: 0,
  address: 'localhost:27017'
}
```

--------------------------------

### Start Azure Function Locally

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/azure-functions

Run this command from your project's root directory to start your Azure Function locally. The CLI will output the local URL for your function.

```bash
func start
```

--------------------------------

### Sample Order with Insufficient Inventory

Source: https://www.mongodb.com/docs/drivers/node/current/crud/transactions/transaction-conv

An example order that will fail due to insufficient inventory for one of the items.

```javascript
{ item: "volleyball", qty: 1 }
```

--------------------------------

### Install socks Package

Source: https://www.mongodb.com/docs/drivers/node/current/security/socks

Install the 'socks' package to enable SOCKS5 proxy support in your application. This is required for Node.js driver versions 6.0 and later.

```bash
npm i socks
```

--------------------------------

### Example Aggregation Output

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/retrieve

This is an example of the output format you might receive after running an aggregation query that groups documents by status and counts them.

```json
[
  { _id: 'delivering', count: 5 },
  { _id: 'delivered', count: 37 },
  { _id: 'created', count: 9 }
]
```

--------------------------------

### Example Output of find() Operation

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/retrieve

This is the expected output format when running the TypeScript find() example. It shows a list of documents with the projected fields.

```javascript
{ title: '10 Minutes', imdb: { rating: 7.9, votes: 743, id: 339976 } }
{ title: '3x3', imdb: { rating: 6.9, votes: 206, id: 1654725 } }
{ title: '7:35 in the Morning', imdb: { rating: 7.3, votes: 1555, id: 406501 } }
{ title: '8', imdb: { rating: 7.8, votes: 883, id: 1592502 } }
...
```

--------------------------------

### TopologyOpeningEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

This event is emitted when a topology is opening. It contains the topology ID.

```javascript
TopologyOpeningEvent {
  topologyId: 0
}
```

--------------------------------

### Basic Replace Operation Example

Source: https://www.mongodb.com/docs/drivers/node/current/crud/update/replace

Demonstrates a basic `replaceOne` operation. This example replaces a document matching the `_id` filter with a new document containing different item details.

```javascript
const myDB = client.db("myDB");
const myColl = myDB.collection("items");

const filter = { _id: 501 };

// replace the matched document with the replacement document
const replacementDocument = {
   item: "Vintage silver flatware set",
   price: 79.15,
   quantity: 1,
};
const result = await myColl.replaceOne(filter, replacementDocument);
```

--------------------------------

### Insert Sample Documents

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/distinct

Inserts sample documents into the 'restaurants' collection for use in distinct value retrieval examples.

```javascript
const myDB = client.db("myDB");
const myColl = myDB.collection("restaurants");

await myColl.insertMany([
  { "_id": 1, "restaurant": "White Bear", "borough": "Queens", "cuisine": "Chinese" },
  { "_id": 2, "restaurant": "Via Carota", "borough": "Manhattan", "cuisine": "Italian" },
  { "_id": 3, "restaurant": "Borgatti's", "borough": "Bronx", "cuisine": "Italian" },
  { "_id": 4, "restaurant": "Tanoreen", "borough": "Brooklyn", "cuisine": "Middle Eastern" },
  { "_id": 5, "restaurant": "Äpfel", "borough": "Queens", "cuisine": "German" },
  { "_id": 6, "restaurant": "Samba Kitchen", "borough": "Manhattan", "cuisine": "Brazilian" },
]);
```

--------------------------------

### Install MongoDB Node.js Driver

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/azure-functions

Install the MongoDB Node.js driver from the project root using npm. This command adds the driver to your project dependencies.

```bash
npm install mongodb
```

--------------------------------

### Count Documents Example: Full File

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/count

This example estimates the total number of documents in a collection and then provides an accurate count of documents matching a specific query. Ensure you have a MongoDB connection string and the 'sample_mflix' database with the 'movies' collection loaded.

```javascript
import { MongoClient } from "mongodb";

// Replace the uri string with your MongoDB deployment's connection string
const uri = "<connection string uri>";

const client = new MongoClient(uri);

async function run() {
  try {
    const database = client.db("sample_mflix");
    const movies = database.collection("movies");

    /* Print the estimate of the number of documents in the
    "movies" collection */
    const estimate = await movies.estimatedDocumentCount();
    console.log(`Estimated number of documents in the movies collection: ${estimate}`);

    /* Print the number of documents in the "movies" collection that
    match the specified query */
    const query = { countries: "Canada" };
    const countCanada = await movies.countDocuments(query);
    console.log(`Number of movies from Canada: ${countCanada}`);
  } finally {
    // Close the connection after the operations complete
    await client.close();
  }
}
// Run the program and print any thrown exceptions
run().catch(console.dir);

```

--------------------------------

### TopologyDescriptionChangedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

This event details changes in the MongoDB deployment's topology, such as transitioning between states like 'ReplicaSetNoPrimary' and 'ReplicaSetWithPrimary'.

```javascript
TopologyDescriptionChangedEvent {
  topologyId: 0,
  previousDescription: TopologyDescription {
    type: 'ReplicaSetNoPrimary',
    setName: null,
    maxSetVersion: null,
    maxElectionId: null,
    servers: Map {
      'localhost:27017' => ServerDescription
    },
    stale: false,
    compatible: true,
    compatibilityError: null,
    logicalSessionTimeoutMinutes: null,
    heartbeatFrequencyMS: 10000,
    localThresholdMS: 15,
    options: Object,
    error: undefined,
    commonWireVersion: null
  },
  newDescription: TopologyDescription {
    type: 'ReplicaSetWithPrimary',
    setName: 'rs',
    maxSetVersion: 1,
    maxElectionId: null,
    servers: Map {
      'localhost:27017' => ServerDescription
    },
    stale: false,
    compatible: true,
    compatibilityError: null,
    logicalSessionTimeoutMinutes: 30,
    heartbeatFrequencyMS: 10000,
    localThresholdMS: 15,
    options: Object,
    error: undefined,
    commonWireVersion: 7
  }
}
```

--------------------------------

### ServerDescriptionChangedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

This event is emitted when the description of a server changes. It includes details about the topology, server address, and the previous and new server descriptions.

```javascript
ServerDescriptionChangedEvent {
  topologyId: 0,
  address: 'localhost:27017',
  previousDescription: ServerDescription {
    address: 'localhost:27017',
    error: null,
    roundTripTime: 0,
    lastUpdateTime: 1571251089030,
    lastWriteDate: null,
    opTime: null,
    type: 'Unknown',
    minWireVersion: 0,
    maxWireVersion: 0,
    hosts: [],
    passives: [],
    arbiters: [],
    tags: []
  },
  newDescription: ServerDescription {
    address: 'localhost:27017',
    error: null,
    roundTripTime: 0,
    lastUpdateTime: 1571251089051,
    lastWriteDate: 2019-10-16T18:38:07.000Z,
    opTime: { ts: Timestamp, t: 18 },
    type: 'RSPrimary',
    minWireVersion: 0,
    maxWireVersion: 7,
    maxBsonObjectSize: 16777216,
    maxMessageSizeBytes: 48000000,
    maxWriteBatchSize: 100000,
    me: 'localhost:27017',
    hosts: [ 'localhost:27017' ],
    passives: [],
    arbiters: [],
    tags: [],
    setName: 'rs',
    setVersion: 1,
    electionId: ObjectID,
    primary: 'localhost:27017',
    logicalSessionTimeoutMinutes: 30,
    '$clusterTime': ClusterTime
  }
}
```

--------------------------------

### Initialize Node.js Project

Source: https://www.mongodb.com/docs/drivers/node/current/connect/multiple-connections

Create a new directory and initialize a Node.js project using npm. This sets up the basic project structure.

```bash
mkdir mongodb-multiple-connections
cd mongodb-multiple-connections
npm init -y
```

--------------------------------

### Execute 'hello' Command with `command()`

Source: https://www.mongodb.com/docs/drivers/node/current/run-command

Use the `command()` method to run the 'hello' command, which retrieves information about the current replica set member's role. This method is suitable for any database command.

```javascript
const result = await myDB.command({ hello: 1 });
```

--------------------------------

### Get Distinct Years with Director Filter (TypeScript)

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/distinct

Retrieves a list of distinct 'year' values from the 'movies' collection where the director is 'Barbra Streisand', using TypeScript. This example includes an interface for type safety.

```typescript
import { MongoClient } from "mongodb";

// Replace the uri string with your MongoDB deployment's connection string.
const uri = "<connection string uri>";

const client = new MongoClient(uri);

interface Movie {
  directors: string;
  year: number;
}

async function run() {
  try {
    // define a database and collection on which to run the method
    const database = client.db("sample_mflix");
    const movies = database.collection<Movie>("movies");

    const distinctValues = await movies.distinct("year", {
      directors: "Barbra Streisand",
    });

    console.log(distinctValues);
  } finally {
    await client.close();
  }
}
run().catch(console.dir);

```

--------------------------------

### updateOne() Example in JavaScript

Source: https://www.mongodb.com/docs/drivers/node/current/crud/update/modify

Use `updateOne()` to modify the first document that matches the filter criteria. The `upsert: true` option will insert a new document if no match is found. Ensure you have the MongoDB Node.js driver installed and a connection string URI.

```javascript
// Update a document

import { MongoClient } from "mongodb";

// Replace the uri string with your MongoDB deployment's connection string
const uri = "<connection string uri>";

const client = new MongoClient(uri);

async function run() {
  try {
    const database = client.db("sample_mflix");
    const movies = database.collection("movies");

    // Create a filter for movies with the title "Random Harvest"
    const filter = { title: "Random Harvest" };

    /* Set the upsert option to insert a document if no documents match
    the filter */
    const options = { upsert: true };

    // Specify the update to set a value for the plot field
    const updateDoc = {
      $set: {
        plot: `A harvest of random numbers, such as: ${Math.random()}`
      },
    };

    // Update the first document that matches the filter
    const result = await movies.updateOne(filter, updateDoc, options);
    
    // Print the number of matching and modified documents
    console.log(
      `${result.matchedCount} document(s) matched the filter, updated ${result.modifiedCount} document(s)`,
    );
  } finally {
    // Close the connection after the operation completes
    await client.close();
  }
}
// Run the program and print any thrown errors
run().catch(console.dir);

```

--------------------------------

### Subscribe to SDAM Events

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Connect to a replica set and subscribe to specific SDAM events like 'serverOpening'. This example demonstrates how to log event details when they occur.

```javascript
const client = new MongoClient(uri);
const eventName = 'serverOpening';

client.on(eventName, (event) =>
  console.log(`received ${eventName}: ${JSON.stringify(event, null, 2)}`)
);

try {
  await client.db('admin').command({ ping: 1 });
} finally {
  await client.close();
}

```

--------------------------------

### Initialize Mongoose Application

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/mongoose/mongoose-qe

Sets up the main application file with necessary imports and a placeholder for the main execution function. Ensure all required npm packages are installed.

```javascript
import 'dotenv/config';
import mongoose from 'mongoose';
import * as qeHelper from './queryable-encryption-helpers.js';
import { MongoClient, ClientEncryption } from 'mongodb';

async function runExample() {

  // Paste initial application variables below

  // Paste credential and options variables below

  // Paste connection and client configuration below

  // Paste data key creation code below

  // Paste encryption schema below

  // Paste the model below

  // Paste connection code below

  // Paste the insertion operation below

  // Paste the encrypted query below

  await connection.close();
  console.log('Connection closed.');
}

runExample().catch(console.dir);


```

--------------------------------

### ConnectionPoolClosedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionPoolClosed event. This event is emitted when a connection pool is closed.

```javascript
ConnectionPoolClosedEvent {
  time: 2023-02-13T15:56:38.440Z,
  address: '...'
}
```

--------------------------------

### Set Up Environment Variables

Source: https://www.mongodb.com/docs/drivers/node/current/connect/multiple-connections

Create a .env file to store your MongoDB connection strings. Ensure you replace the placeholder values with your actual connection strings.

```javascript
PRIMARY_CONN_STR=<your-primary-connection-string>
SECONDARY_CONN_STR=<your-secondary-connection-string>
```

--------------------------------

### ConnectionCheckedOutEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionCheckedOut event. This event signifies that an operation has successfully acquired a connection.

```javascript
ConnectionCheckedOutEvent {
  time: 2023-02-13T15:54:07.188Z,
  address: '...',
  connectionId: 1,
  durationMS: 60
}
```

--------------------------------

### Create Next.js App with MongoDB Example

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/next-vercel

Use this command to scaffold a new Next.js application pre-configured with MongoDB integration. Replace 'sample_mflix' with your desired project name.

```bash
npx create-next-app --example with-mongodb sample_mflix
```

--------------------------------

### ConnectionPoolCreatedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionPoolCreated event. This event signifies the creation of a new connection pool.

```javascript
ConnectionPoolCreatedEvent {
  time: 2023-02-13T15:54:06.944Z,
  address: '...',
  options: {...}
}
```

--------------------------------

### Example Documents Matching a Phrase

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/text

These documents are examples of results returned when searching for the phrase 'star trek'.

```json
{ title: 'Star Trek' }
{ title: 'Star Trek Into Darkness' }
{ title: 'Star Trek: Nemesis' }
{ title: 'Star Trek: Insurrection' }
{ title: 'Star Trek: Generations' }
{ title: 'Star Trek: First Contact' }
{ title: 'Star Trek: The Motion Picture' }
{ title: 'Star Trek VI: The Undiscovered Country' }
{ title: 'Star Trek V: The Final Frontier' }
{ title: 'Star Trek IV: The Voyage Home' }
{ title: 'Star Trek III: The Search for Spock' }
{ title: 'Star Trek II: The Wrath of Khan' }
```

--------------------------------

### Create Project Directory

Source: https://www.mongodb.com/docs/drivers/node/current/get-started

Use these commands to create a new directory for your Node.js project and initialize it with npm.

```bash
mkdir node_quickstart
```

```bash
cd node_quickstart
npm init -y
```

--------------------------------

### ConnectionPoolClearedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionPoolCleared event. This event indicates that all connections in the pool have been closed and the pool is cleared.

```javascript
ConnectionPoolClearedEvent {
  time: 2023-02-13T15:56:38.439Z,
  address: '...',
  serviceId: undefined,
  interruptInUseConnections: true
}
```

--------------------------------

### Navigate to Project Directory

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/next-vercel

After creating the Next.js application, change into the project directory using this command.

```bash
cd sample_mflix
```

--------------------------------

### ConnectionCreatedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionCreated event. This event is triggered when a new connection is established within the pool.

```javascript
ConnectionCreatedEvent {
  time: 2023-02-13T15:56:38.291Z,
  address: '...',
  connectionId: 1
}
```

--------------------------------

### Example Documents After Negation

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/text

These documents are examples of results returned after excluding the phrase 'into darkness' from the 'star trek' search.

```json
{ title: 'Star Trek' }
{ title: 'Star Trek: Nemesis' }
{ title: 'Star Trek: Insurrection' }
{ title: 'Star Trek: Generations' }
{ title: 'Star Trek: First Contact' }
{ title: 'Star Trek: The Motion Picture' }
{ title: 'Star Trek VI: The Undiscovered Country' }
{ title: 'Star Trek V: The Final Frontier' }
{ title: 'Star Trek IV: The Voyage Home' }
{ title: 'Star Trek III: The Search for Spock' }
{ title: 'Star Trek II: The Wrath of Khan' }
```

--------------------------------

### Insert Sample Documents

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/project

Inserts sample fruit documents into the 'fruits' collection for use in projection examples. Ensure the MongoDB client is connected before running.

```javascript
const myDB = client.db("myDB");
const myColl = myDB.collection("fruits");

await myColl.insertMany([
  { "_id": 1, "name": "apples", "qty": 5, "rating": 3 },
  { "_id": 2, "name": "bananas", "qty": 7, "rating": 1 },
  { "_id": 3, "name": "oranges", "qty": 6, "rating": 2 },
  { "_id": 4, "name": "avocados", "qty": 3, "rating": 5 },
]);
```

--------------------------------

### ConnectionClosedEvent Example

Source: https://www.mongodb.com/docs/drivers/node/current/monitoring-and-logging/monitoring

Example output for a connectionClosed event. This event is emitted when a connection is closed, potentially due to pool closure or other reasons.

```javascript
ConnectionClosedEvent {
  time: 2023-02-13T15:56:38.439Z,
  address: '...',
  connectionId: 1,
  reason: 'poolClosed',
  serviceId: undefined
}
```

--------------------------------

### Install MongoDB Node.js Driver

Source: https://www.mongodb.com/docs/drivers/node/current/get-started

Install the MongoDB Node.js driver version 7.3 into your project. This command also updates your package.json file.

```bash
npm install mongodb@7.3
```

--------------------------------

### Seed MongoDB Database with Sample Data

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/prisma

Populate your MongoDB database with sample data by running the Prisma seed script. This command creates the collections defined in your `schema.prisma` file.

```shell
npx prisma db seed
```

--------------------------------

### Configure Database Options

Source: https://www.mongodb.com/docs/drivers/node/current/crud/configure

Set read preference, read concern, and write concern for a specific database by passing a DbOptions object to the db() method. This example configures primary preferred read preference, available read concern, and a majority write concern.

```javascript
const dbOptions = {
  readPreference: ReadPreference.PRIMARY_PREFERRED,
  readConcern: { level: "available" },
  writeConcern: { w: "majority" },
};

const db = client.db("test_database", dbOptions);
```

--------------------------------

### Create a GridFS Bucket Instance

Source: https://www.mongodb.com/docs/drivers/node/current/crud/gridfs

Instantiate a GridFSBucket to interact with GridFS. Pass the database object as a parameter. The default bucket name is 'fs'.

```javascript
const db = client.db(dbName);
const bucket = new mongodb.GridFSBucket(db);
```

--------------------------------

### Example Documents Sorted by Relevance

Source: https://www.mongodb.com/docs/drivers/node/current/crud/query/text

These documents are examples of results sorted by their text relevance score, with higher scores indicating greater relevance.

```json
{ title: 'Star Trek', score: 1.5 }
{ title: 'Star Trek: Generations', score: 1.3333333333333333 }
{ title: 'Star Trek: Insurrection', score: 1.3333333333333333 }
{ title: 'Star Trek: Nemesis', score: 1.3333333333333333 }
{ title: 'Star Trek: The Motion Picture', score: 1.25 }
{ title: 'Star Trek: First Contact', score: 1.25 }
{ title: 'Star Trek II: The Wrath of Khan', score: 1.2 }
{ title: 'Star Trek III: The Search for Spock', score: 1.2 }
{ title: 'Star Trek IV: The Voyage Home', score: 1.2 }
{ title: 'Star Trek V: The Final Frontier', score: 1.2 }
{ title: 'Star Trek VI: The Undiscovered Country', score: 1.2 }
```

--------------------------------

### Configure MongoDB Connection and Client

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/mongoose/mongoose-qe

Sets up a Mongoose connection for encrypted operations, a MongoDB client for key management, and a ClientEncryption instance. It also drops existing databases for a clean setup.

```javascript
const connection = mongoose.createConnection();

const client = new MongoClient(uri);
const clientEncryption = new ClientEncryption(
  client,
  autoEncryptionOptions
);

await qeHelper.dropExistingDatabase(client, encryptedDatabaseName);
await qeHelper.dropExistingDatabase(client, keyVaultDatabaseName);
```

--------------------------------

### Install Validator Package

Source: https://www.mongodb.com/docs/drivers/node/current/integrations/mongoose/mongoose-get-started

Install the 'validator' package using npm, which is used for validating data formats like email addresses within Mongoose middleware.

```bash
npm install validator
```

--------------------------------

### Install Dotenv Package

Source: https://www.mongodb.com/docs/drivers/node/current/connect/multiple-connections

Install the dotenv package to load environment variables from your .env file into your Node.js application. This is crucial for managing connection strings securely.

```bash
npm install dotenv
```

--------------------------------

### Enable TLS with Connection String

Source: https://www.mongodb.com/docs/drivers/node/current/security/tls

Set the `tls` option to `true` in your connection string to enable TLS for the connection.

```js
const uri = "mongodb://<hostname>:<port>?tls=true";
const client = new MongoClient(uri, myClientSettings);
```

--------------------------------

### Configure MongoClient Options

Source: https://www.mongodb.com/docs/drivers/node/current/crud/configure

Set default read preference, read concern, and write concern for all operations by passing options to the MongoClient constructor. This example configures secondary read preference, local read concern, and a write concern of 'w: 2'.

```javascript
const clientOptions = {
  readPreference: ReadPreference.SECONDARY,
  readConcern: { level: "local" },
  writeConcern: { w: 2 },
};

const client = new MongoClient("mongodb://localhost:27017", clientOptions);
```

--------------------------------

### Connect to Replica Set

Source: https://www.mongodb.com/docs/drivers/node/current/connect/connection-targets

Connect to a replica set by listing all nodes in the connection string for resilience. The driver can also discover remaining nodes if only one is specified.

```javascript
const client = new MongoClient("mongodb://host1:27017,host2:27017,host3:27017/?replicaSet=myRs");
```
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