Build a REST API in Four Simple Steps

Build a REST API in four simple steps.

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— Pratham (@Prathkum) June 19, 2023

Step 1: Install Node.js

I'm assuming you have Node.js installed on your machine. If you haven't installed it, click on the following link and install it simply.https://t.co/xKueCxRAUd

— Pratham (@Prathkum) June 19, 2023

Step 2: Initialize the project

Let's start; create an empty directory and initialize your project by running the following command. pic.twitter.com/5m6Da2qFpW

— Pratham (@Prathkum) June 19, 2023

The next step is to create an empty JavaScript file (File name could be anything, in this case, it's index.js) and install Express.

🔗 https://t.co/Yw1oLDvoOc

Express is a minimal and easy-to-learn framework for Node. pic.twitter.com/dXPa2KSZq1

— Pratham (@Prathkum) June 19, 2023

Step 3: Starting the server

Now that everything is ready, it's time to code our actual API.

Let's start the server first.

In the below code snippet, we are initializing our `app` and starting the local server at port 3000.

Run `node index.js` to start the server. pic.twitter.com/w9qf3M5uPZ

— Pratham (@Prathkum) June 19, 2023

For more context, listen() function is used to establish the connection on specified host and port.

It takes two params:

- The first is the port number or host.

- The second (optional) is a callback function that runs after listening to a specified host or value.

— Pratham (@Prathkum) June 19, 2023

Moving forward, let's try to access "localhost:3000" in the browser and see what we are getting.

We are getting a "404 Not Found" response which is correct as we haven't defined any endpoints yet. pic.twitter.com/4vI4PXeiBS

— Pratham (@Prathkum) June 19, 2023

I prefer RapidAPI Client for VS Code extension to test and build API in VS Code.

You can for other options as well like Postman, Thunder Client, etc.

Go ahead and install it.

🔗 https://t.co/FR0QhyTi8v pic.twitter.com/Rd8CCZntkv

— Pratham (@Prathkum) June 19, 2023

As now our server is running successfully at port 3000, let's create an endpoint.

— Pratham (@Prathkum) June 19, 2023

Step 4: Create Endpoints

The `get` method allows us to create HTTP GET requests.

It accepts two params:

- The first is path/route.

- The second is a callback function that handles the request to the specified route. pic.twitter.com/3OQaqjv3ce

— Pratham (@Prathkum) June 19, 2023

The callback function itself accepts two arguments:

- The first is the request which is the data to the server.

- The second is the response which is the data to the client. pic.twitter.com/nqNeIT9Vmh

— Pratham (@Prathkum) June 19, 2023

Suppose you want to display all the users whenever the client requests the "/users" endpoint.

To return the data from the server to the client, we have the `send` method.

In the code snippet below, we send an array of objects with `name` and `id` fields. pic.twitter.com/BiuW1F7zUs

— Pratham (@Prathkum) June 19, 2023

Perfect!

Let's restart the server by running the `node index.js` command and see what we are getting. pic.twitter.com/ymAS8GPOAT

— Pratham (@Prathkum) June 19, 2023

You can make as many endpoints as you want using the same technique.

For demonstration purposes, let's quickly create a POST request endpoint.

— Pratham (@Prathkum) June 19, 2023

As POST request is to create or add new data to the server. We first need to add middleware so that we can parse the JSON body. pic.twitter.com/Isvcq56QJt

— Pratham (@Prathkum) June 19, 2023

We are defining a POST endpoint at the "/user/3" route.

We implemented the logic of throwing a "400 Bad Request" status code if the user forgets to pass the name value in the request body. pic.twitter.com/aNtj6ujYkL

— Pratham (@Prathkum) June 19, 2023

Let's try to access this endpoint now. pic.twitter.com/BGYNeKNNe5

— Pratham (@Prathkum) June 19, 2023

As you can see, we are getting a response. 🎉

Great! We have just built a REST API.

— Pratham (@Prathkum) June 19, 2023