Getting Started

You will first need to create a directory, access it in your shell and install Express using npm by running npm install express --save

Create a file and name it app.js and add the following code which creates a new Express server and adds one endpoint to it (/ping) with the app.get method:

const express = require('express');

const app = express();

app.get('/ping', (request, response) => {
    response.send('pong');
});

app.listen(8080, 'localhost');

To run your script use the following command in your shell:

> node app.js

Your application will accept connections on localhost port 8080. If the hostname argument to app.listen is omitted, then server will accept connections on the machine’s IP address as well as localhost. If port value is 0, the operating system will assign an available port.

Once your script is running, you can test it in a shell to confirm that you get the expected response, “pong”, from the server:

> curl http://localhost:8080/ping
pong

You can also open a web browser, navigate to the url http://localhost:8080/ping to view the output