Exploring MongoDB Atlas and TypeScript with Express: A Step-by-Step Guide

In this tutorial, we'll explore how to connect your Node.js application to a MongoDB Atlas database using TypeScript and Express. We'll also learn about the benefits of using TypeScript and its compatibility with existing JavaScript libraries.

Before we begin, it's essential to note that this project is already set up with Express and TypeScript configurations, making it easy for you to get started quickly. To follow along, simply clone the companion repository from GitHub and navigate to the root directory in your terminal.

First, let's install the MongoDB Node.js driver using npm by running the command `npm install mongodb`. This will allow us to connect to our MongoDB Atlas database.

Once installed, we'll need to add our MongoDB Atlas connection string. To do this, open the `.env` file in the root directory and update it with your own connection string. For example:

```javascript

MONGO_URI=mongodb+srv://username:password@cluster0-shard-repl.set.mongodb.net/myFirstDatabase?retryWrites=true&w=majority

```

Replace `username`, `password`, and `myFirstDatabase` with your actual Atlas credentials.

Next, let's create a model to interact with our database. In this example, we'll use the MongoDB Compass Filter Example to filter documents based on specific criteria.

```javascript

import { MongoClient } from 'mongodb';

const client = new MongoClient(MONGO_URI);

async function getFilteredDocuments(filter: any) {

const collection = client.collection('myCollection');

const cursor = collection.find(filter);

return await cursor.toArray();

}

export default getFilteredDocuments;

```

In this example, we're using the MongoDB Compass Filter Example to filter documents based on a specific query. The `getFilteredDocuments` function takes an object with filter criteria as an argument and returns an array of matching documents.

To test our model, let's create a new file called `app.js` and add the following code:

```javascript

import express from 'express';

import { getFilteredDocuments } from './model';

const app = express();

app.get('/api/filter', async (req, res) => {

const filter = { name: 'John' };

const documents = await getFilteredDocuments(filter);

res.json(documents);

});

app.listen(3000, () => {

console.log('Server listening on port 3000');

});

```

In this example, we're creating an Express server that listens for requests to the `/api/filter` endpoint. When a request is made, we're using our `getFilteredDocuments` model to filter documents based on the specified query and returning the results in JSON format.

That's it! With these steps, you should now have a basic understanding of how to connect your Node.js application to a MongoDB Atlas database using TypeScript and Express. By following this tutorial, you'll be able to filter documents using the MongoDB Compass Filter Example and enjoy the benefits of type-safety provided by TypeScript.

In this article, we explored how to connect a Node.js application to a MongoDB Atlas database using TypeScript and Express. We also learned about the benefits of using TypeScript and its compatibility with existing JavaScript libraries. By following this tutorial, you should now have a solid foundation for building robust and maintainable web applications using MongoDB Atlas and TypeScript.

Mongodb compass filter example