qr-reader

Nodejs QR code reader library. It's simple just return the QR string.

Requirement note

Enable a carriage return/line feed (enter key) suffix in QR device or this library not working properly.

Installation

To install via npm:

npm install --save @ahmadaidil/qr-reader

To install via yarn:

yarn add @ahmadaidil/qr-reader

Usage

Opening a device

input the qr device product id, vendor id and serial number at the param object

object key	type	description
productId	number	device product id
vendorId	number	device vendor id
serialNumber	string	device serial number

const QRReader = require('@ahmadaidil/qr-reader')

const device = new QRReader({
  productId: 4608,
  vendorId: 1504,
  serialNumber: '20241523701421'
})

device.on('open', msg => console.log(msg)) // QR device with PID 4608, VID 1504 and SN 20241523701421 is now open!

Reading from a device

To receive the QR string, use device.on('data',...). A qr-reader device is an EventEmitter. Reading from a device is performed by registering a "data" event handler:

device.on('data', qrString => {});

You can also listen for errors like this:

device.on('error', err => {});

Notes:

• Reads via device.on('data') are asynchronous
• To remove an event handler, close the device with device.close()
• When there is not yet a data handler or no data handler exists, data is not read at all.

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©2021 Ahmad Aidil