How to create or generate QR code using Node.js

In this post I would like to explain about how to create or generate the QR code using Node.js with dynamic data. It is simple code to generate the code, but it will help in many of our applications.

• For the accessing any content or links rather than display directly, display it in QR codes. It is a secure way to display those contents.
• What we are going to achieve with QR code, simple display it in your website for the apps links, websites, amount related.


How to create or generate QR code using Node.js by Anil Labs

• How we are going to create or generate it
  1. As earlier explained about install the Nodejs in your system.
  2. How to install the packages
  To install any packages we have to follow below command to install it globally

  npm install -g [package name]

  To install any packages we have to follow below command to install it application

  npm install –save [package name]

  3. In our application we need to install the below packages

  npm install --save body-parser
  npm install --save express
  npm install --save fs
  npm install --save path
  npm install --save qrcode

  4. Write the PORT number inside of your index.js or app.js file

  const PORT = 3000

  5. Include the all packages in your app file

  const express = require('express');
  var bodyParser = require('body-parser');
  var path = require('path');
  var fs = require("fs");
  var QRCode = require('qrcode');

  6. Include the body parser and express in your code

  var app = express();
  app.set('view engine', 'html');
  app.use(bodyParser.json({limit: '50mb'}));
  // parse requests of content-type - application/json
  //app.use(bodyParser.urlencoded({ extended: true }))
  app.use(bodyParser.urlencoded({ extended: true ,keepExtensions: true}));
  // parse requests of content-type - application/json
  app.use(bodyParser.json())

  7. CORS for our application

  app.use(function(req, res, next) { //allow cross origin requests
  res.setHeader("Access-Control-Allow-Methods", "POST, PUT, OPTIONS, DELETE, GET");
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
  next();
  });

  8. Middileware for our application

  const logger = function (req, res, next) {
    //console.log(req)
    next()
  }
  
  app.use(logger)

  9. Generate the QR code with provide text

  app.get('/', (req, res) => {
      QRCode.toDataURL('https://anillabs.com', function (err, url) {
          templatePath = path.join(__dirname + '/code.html');
          fs.readFile(templatePath, {encoding: 'utf-8'}, function(err,data){
              data = data.replace(/##qUrl/g, url);
              res.send(data)
          })
        })
  })

  10. Application listen

  app.listen(PORT, () => console.log('Anil Labs QR Code generation on the port: ' + PORT))

  11. To display the code in your HTML file

  <img src="##qUrl" />

  12. Run the application

  node index.js

How to create or generate QR code using Node.js by Anil Labs