Meteor Community Logo

Meteor Community

Packosphere

undefined's Avatar

froatsnook:bardcode

v1.2.0•Published 11 years ago

This package has not had recent updates. Please investigate it's current state before committing to using it in your project.

Render 1-D barcodes to canvas or svg. Supports Code 128, 3 of 9, 2 of 5, EAN, and more.

Why?

This barcode library specializes in its use of the canvas API. You provide a canvas (be it in a browser or with node-canvas), and then specify where the barcode should be drawn, how large it should be, and at what angle.

Other barcode libraries that I found created pngs or svgs directly and were not very flexible in the output size (i.e. no maxWidth option). Rendering directly to a canvas allows for a flexible API if that's your target anyway.

Demos/Playground

First of all, check out the demos.

How?

1// In the browser
2var canvas = document.getElementById("barcode-canvas");
3var g = canvas.getContext("2d");
4drawBarcode(g, "Test barcode", options);
1// On the server
2var bardcode = require("bardcode");
3var Canvas = require("canvas");
4var canvas = new Canvas(595, 842, "pdf");
5var g = canvas.getContext("2d");
6bardcode.drawBarcode(g, "Test barcode", options);
1// Meteor server
2var Canvas = Meteor.npmRequire("canvas");
3var canvas = new Canvas(595, 842, "pdf");
4var g = canvas.getContext("2d");
5drawBarcode(g, "Test barcode", options);

Symbology

The following barcode formats are supported:

  • Codabar
  • Code 128
  • Code 39
  • EAN-8
  • EAN-13
  • FIM
  • ITF (interleaved 2 of 5)
  • UPC-A

API

1// browser+meteor
2drawBarcode(g, barcodeText, options);
3
4// node
5var bardcode = require("bardcode");
6bardcode.drawBarcode(g, barcodeText, options);
  • g is a Canvas' 2-D graphics context or the output format. The only supported non-canvas output format is "svg".
  • barcodeText is a string. Allowed characters depend on the chosen symbology.
  • options is an optional object with the following properties:
    • options.type Barcode type. Defaults to Code 128. Other valid options are "Codabar", "Code 39", "EAN-8", "EAN-13", "FIM", "ITF" (interleaved 2 of 5), and "UPC-A".
    • options.hasChecksum If true, the barcode already has a checksum (which will be validated); if false, calculate and add a checksum. Defaults to false. Currently works only for EAN-type barcodes (EAN-8, EAN-13, UPC-A).
    • options.x Where to draw barcode. Defaults to 0.
    • options.y Where to draw the barcode. Defaults to 0.
    • options.horizontalAlign How to align the barcode. Defaults to "left". Other options are "center" and "right".
    • options.verticalAlign How to align the barcode. Defaults to "top". Other options are "middle" and "bottom".
    • options.height Barcode height. Defaults to 90.72.
    • options.moduleWidth Width of thinnest bar. Defaults to 2.892.
    • options.quietZoneSize Number of moduleWidths in quiet zone on either side. Defaults to 10.
    • options.angle Rotate barcode this many degrees clockwise. Defaults to 0.
    • options.maxWidth Maximum barcode width (including quiet zones). If specified, then the moduleWidth will be adjusted if necessary to make the entire barcode fit in the given width.
    • options.width If given, then ignore moduleWidth and maxWidth and set the moduleWidth so that the barcode will have the given width (including quiet zones).

Note: width and maxWidth refer to the unrotated barcode width.

SVG

If the first parameter to bardcode.drawBarcode, g, is "svg", then an SVG string is returned.

For the moment, the only supported options when using SVG are:

  • options.type
  • options.height
  • options.moduleWidth
  • options.quietZoneSize
  • options.maxWidth
  • options.width

Errors

Errors are thrown on invalid input, for example when including letters in EAN barcodes.

Installation

node-canvas installation causes issues for a lot of users. So it's an optional dependency (i.e. you should Bring Your Own Canvas). It's also not a node dependency because it's not the only output format.

For the browser:

  • Include dist/bardcode.js or dist/bardcode.min.js

For node:

  • npm install canvas (requires cairo)
  • npm install bardcode

For meteor:

  • (optional) meteor add meteorhacks:npm and add "canvas": "1.1.6" to packages.json
  • meteor add froatsnook:bardcode

Testing

Tests require meteor and zbar.

  • Download zbar: http://zbar.sourceforge.net/
  • ./configure --disable-video --without-qt --without-gtk --without-python
  • make
  • Copy zbarimg/zbarimg and zbar/.libs/libzbar.so* to a new directory called zbar in bardcode's project directory
  • meteor test-packages ./ in bardcode's project directory
  • Open localhost:3000 in a browser

Contributors

Thank you:

License

MIT