Originally forked from here

ESC/POS XML

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

Features

<input checked="" disabled="" type="checkbox"> Text
<input checked="" disabled="" type="checkbox"> Text line
<input checked="" disabled="" type="checkbox"> Feed line
<input checked="" disabled="" type="checkbox"> Bold text
<input checked="" disabled="" type="checkbox"> Underline text
<input checked="" disabled="" type="checkbox"> Font size
<input checked="" disabled="" type="checkbox"> Small mode
<input checked="" disabled="" type="checkbox"> White mode
<input checked="" disabled="" type="checkbox"> Align
<input checked="" disabled="" type="checkbox"> Barcode
<input checked="" disabled="" type="checkbox"> QRcode
<input checked="" disabled="" type="checkbox"> Paper cut node
<input checked="" disabled="" type="checkbox"> Image (base64) (png only)
<input checked="" disabled="" type="checkbox"> XML with mustache

Tested manually on following environments or platforms

<input checked="" disabled="" type="checkbox"> React Native (Android)
<input checked="" disabled="" type="checkbox"> React Native (iOS)
<input checked="" disabled="" type="checkbox"> React Native Web
<input checked="" disabled="" type="checkbox"> Server side (NodeJs)
<input checked="" disabled="" type="checkbox"> Desktop applications (nwjs & electron)
<input checked="" disabled="" type="checkbox"> Other node environment (terminal)

Installation

  yarn add @tillpos/xml-escpos-helper

Examples

With an XML template + plain object input (regular text).


import { EscPos } from '@tillpos/xml-escpos-helper';

// store this template somewhere `s3` or as `static asset` based on your preference 
const template = `
  <?xml version="1.0" encoding="UTF-8"?>
  <document>
    <align mode="center">
      <bold>
        <text-line size="1:0">{{title}}</text-line>
      </bold>
    </align>

    {{#thankyouNote}}
    <align mode="center">
      <text-line size="0:0">  {{{thankyouNote}}}</text-line>
    </align>

    <line-feed />

    <paper-cut />
  </document>
`;

const input = {
  title: 'Sample',
  thankyouNote: 'Welcome...!'
};

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

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,iVBORw0KGgoAAA+P/AaNn2GPEMgEFAAAAAElFTkSuQmCC`
  };

  const buffer = EscPos.getBufferFromTemplate(template, input);

TODO

<input disabled="" type="checkbox"> Font styles (font family)
<input disabled="" type="checkbox"> Image bitmap conversion improvements
<input disabled="" type="checkbox"> jpeg support
<input disabled="" type="checkbox"> Add example apps to repo
<input disabled="" type="checkbox"> Removed uglify for some reason, need to bring it back
<input disabled="" type="checkbox"> 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 :mask: )

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, jpeg-js and sharp. We can use these libraries with some native node lib implemented in react native (some sort of polyfill).
For png this library seems to be faster, but when tested this library with it, it is not retaining pixels at some places)
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:

Package detail

@tillpos/xml-escpos-helper

readme