xml-to-escpos v1.0.2

XML to ESC/POS

Translation/Tradução

🇧🇷 🇺🇸

Cross platform JavaScript library that implements the thermal printer ESC / POS protocol and provides an XML interface for preparing templates for printing.

Features

• Text
• Text line
• Feed line
• Bold text
• Underline text
• Font size
• Small mode
• White mode
• Align
• QRcode
• Paper cut node
• Image (base64) (png only)
• XML with mustache

Tested manually on following environments or platforms

• React Native (Android)
• React Native (iOS)
• React Native Web
• Server side (NodeJs)
• Desktop applications (nwjs & electron)
• Other node environment (terminal)

Installation

yarn add xml-to-escpos

Or

npm install xml-to-escpos --save

Examples

From plain XML

import { EscPos } from 'escpos-xml';

const xml = `
  <?xml version="1.0" encoding="UTF-8"?>
  <document>
    <text-line>hello world</text-line>
  </document>
`;

const buffer = EscPos.getBufferFromXML(xml);
// send this buffer to a stream (eg.: bluetooth, wifi, usb, etc.)

From XML + Handlebars

import { EscPos } from 'xml-to-escpos';

const xml = `
  <?xml version="1.0" encoding="UTF-8"?>
  <document>
    <text-line>{{foo}}</text-line>
  </document>
`;

const input = {
  foo: 'hello world',
};

const buffer = EscPos.getBufferFromTemplate(template, input);
// send this buffer to a stream (eg.: bluetooth, wifi, usb, etc.)

With an XML template + png image (base64)

const template = `<?xml version="1.0" encoding="UTF-8"?>
  <document>
    <align mode="center">
      <bold>
        <text-line size="1:0">{{title}}</text-line>
      </bold>
        
      <image density="d24">
        {{base64PngImage}}
      </image>
    </align>    
  </document>`;

const input = {
  title: 'PNG - base64',
  base64PngImage: `data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADIAAAAyCAIAAACRXR/mAAAAdklEQVR4nOzQMQ2AUBAEUQInhOCDDq8EAVigQgUaEPA1TLLFFTMCNi9by35Moa5vTU3NqaFsskiySLJIskiySLJIskiySLJIskiySE1Zdf5baut579RU07dkkWSRZJFkkWSRZJFkkWSRZJFkkWSRmrJGAAAA///HQgaco1VmUwAAAABJRU5ErkJggg==`,
};

const buffer = EscPos.getBufferFromTemplate(template, input);
// send this buffer to a stream (eg.: bluetooth, wifi, usb, etc.)

TODO

• Font styles (font family)
• Barcode
• Image bitmap conversion improvements
• jpeg support
• Add example apps to repo
• Removed uglify for some reason, need to bring it back
• Improve image rendering

Common issues

If there is any delay you observe while printing with this library it is mostly due to image manipulations (try without image 😬 )

Useful links / resources

• ESC / POS Commands manual
• A blog post explaiing about printing images with ESCPOS

• Similar library for serverside - node-escpos.

• Limitations on the react-native framework

  • FileReader.readAsArrayBuffer was not implemented.
  • Most of popular image manupulation libraries does not have support for react-native. eg : jimp, Most of popular image manupulation libraries does not have support for react-native. eg : jimp, jpeg-js and sharp. We can use these libraries with some native node lib implemented in react native (some sort of polyfill).
  • Use this node-libs-react-native if we need to use this library in react native (adds some mock or js implementation for fs, stream etc)

  ---

  Contributions of any kind welcome! :heart: