How to create a simple NodeJS HTTP server?

Israr khan — Sat, 03 Sep 2022 16:05:43 +0000

Step 1: Install Node.js

We are assuming you have Node.js installed on your machine. If you haven't installed it, click on the following link and install it simply.
NodeJS

Let's start; create an empty directory and initialize your project by running the following command.

The next step is to create an empty JavaScript file named index.js and install Express.
Express is a minimal and easy-to-learn framework for Node.

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.

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.

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.

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.

The callback function itself accepts two arguments:

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.

Perfect!

Let's restart the server by running the node index.js command and see what we are getting.

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

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

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.

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.

Let's try to access this endpoint now.

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

Great! You just built a REST API.

The DevRel team at @RapidApi originally wrote this thread.

Credits:

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