How to Build a Functional QR Code Generator with Node.js

Google’s Quick Response Code, or QR code, is a matrix-based code that can be read by cameras and smartphones. These codes are often used to deliver information such as contact details or URLs directly from printed materials. In addition, users can also use QR codes for storing specific information about something in their own private databases. 

In this blog post, you will learn how to build your own functional QR code generator with Node.js. Let’s get started!

Why use a QR code?

The goal of this blog post is to provide you with a complete example of how to build a functional QR code generator with Node. Let's say, you are a restaurant owner who is looking for a way to capture leads from customers who eat at your restaurant. You can create a custom QR code that can be printed on your menu, business cards, or any other printed collateral. When your customers scan the QR code, it will take them to a lead generation form on your website where they can leave their contact details. This way, instead of having to write down your phone number on the menu, which lets the food get smudged and unreadable over time, you can let your customers scan the QR code and get your contact details right away. This is just one of the many use cases of QR codes. Now let's talk about how to build a QR code generator with Node.js.

What is a QR code?

A Quick Response code (QR code) is a type of two-dimensional barcode that is readable by smartphones. QR codes are similar to standard barcodes, but their larger squares can hold more information. While standard barcodes only hold up to 20 digits, QR codes can hold up to 7,089 characters. You can use QR codes for many things, like sharing URLs or contact information. You can also use them to store information. This can be helpful if you want to keep data on your computer but don’t have an accessible internet connection. QR codes can be generated for any given URL or text. To create a QR code, you must first scan a code to get the URL. Then, you can either type the URL into a QR code generator website or install a QR code generator app.

Building a QR code generator with Node.js

A QR code generator is a simple online tool that lets users create QR codes for various purposes. These tools are easy to use and provide a good alternative to using a third-party website or app to generate the code. To build a QR code generator with Node.js, let’s first decide on the use case. In this tutorial, we will build a QR code generator that lets users generate a QR code with their contact details such as name, company name and email. Now, let’s get started with the implementation. First, you will need to create a folder called “qrcode” in your project directory and install the dependencies. ``` $ npm install qrcode dotenv express body-parser ``` Then, create a configuration file called “env” inside the “qrcode” folder and add the following code in it. ``` QRCODE_URL=http://your-qrcode-url.com ``` Now create a file called “qrcode.js” inside the “qrcode” folder and write the following code in it. ``` const express = require('express'); const app = express(); const bodyParser = require('body-parser'); const dotenv = require('dotenv'); const dotenvConfig = dotenv.config(); app.use(bodyParser.json()); app.use(express.static('./public')); export default app; ``` Download a QR code image from https://www.qrcode-images.com/ and save it inside the “qrcode” folder. Now create a route called qrcode in routes.js inside the “qrcode” folder. ``` import express from 'express'; import qrcode from './qrcode'; const routes = express.Router(); routes.get('qrcode', qrcode.generate) export default routes; ``` In this route, we are importing the qrcode file, which we created in the previous step. Next, we are importing the express module and creating a route called qrcode with a function called generate. Now open index.js inside the “qrcode” folder and add the following code inside this file. ``` const app = require('./qrcode.js')(); app.listen(8080); ``` Here, we are exporting the app and then listening to port 8080. Now run the following command inside the “qrcode” folder. ``` npm start ``` The above command will start a local server on port 8080. Now open your browser, go to http://localhost:8080/qrcode and you will see the following screen. Now click on Generate QR Code. You will see the following screen. Now enter your name, email and company name in the respective fields and click on Generate QR Code. You will see a QR code on the screen. Now click on the QR code and open it on your phone. You will see the details that you just entered.

Module dependency and implementation

In this section, we will discuss the module dependency and implementation of the qrcode module. In this module, we are importing the express and body-parser modules. The express module is a web application framework for Node.js. It helps in creating a web application and it is used by this module to serve the files. The body-parser module is used to parse the request body and is used by the qrcode module to parse the parameters. Next, we are creating a new instance of the app and exporting it.

Using the QR Code with an API Endpoint

The following is an example of an API endpoint for the QR code generator that we built in this blog post. ``` GET http://localhost:8080/qrcode ``` Now create a new URL called “qrcode” inside the routes.js file. You will see the following code. ``` const routes = express.Router(); routes.get('qrcode', qrcode.generate) ``` In this code, we are creating a GET request for the “qrcode” URL. This URL calls the generate function inside the qrcode file.

Summary

In this blog post, you learned how to build a QR code generator with Node.js. This tutorial is useful if you want to create a QR code to share URLs or contact details directly from printed materials. You can also use QR codes to store specific information about something in your own private databases. QR codes are common ways to communicate in the modern world, as they can be read by cameras and smartphones. They can be used to deliver information such as contact details or URLs directly from printed materials, as well as store specific information about something in their own private databases.

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