Barcodes

Barcode Generation¶

Both report and label templates can render custom barcode data to in-line images.

Barcode Template Tags¶

To use the barcode tags inside a label or report template, you must load the barcode template tags at the top of the template file:

<!-- Load the barcode helper functions -->
{% load barcode %}

Barcode Image Data¶

The barcode template tags will generate an image tag with the barcode data encoded as a base64 image. The image data is intended to be rendered as an img tag:

{% load barcode %}
<img class='custom_class' src='{% barcode "12345678" %}'>

1D Barcode¶

python-barcode

One dimensional barcodes (e.g. Code128) are generated using the python-barcode library.

To render a 1D barcode, use the barcode template tag:

Parameters:

Name	Type	Description	Default
`data`	`str`	Data to encode	required
`barcode_class`	`str`	The type of barcode to generate (default = 'code128')	`'code128'`

Other Parameters:

Name	Type	Description
`format`	`str`	Image format (default = 'PNG')
`fill_color`	`str`	Foreground color (default = 'black')
`back_color`	`str`	Background color (default = 'white')
`scale`	`float`	Scaling factor (default = 1)

Returns:

Name	Type	Description
`image`	`str`	base64 encoded image data

Example¶

<!-- Don't forget to load the barcode helper! -->
{% load barcode %}

<img class='custom_class' src='{% barcode "12345678" %}'>

Additional Options¶

The default barcode renderer will generate a barcode using Code128 rendering. However other barcode formats are also supported:

{% load barcode %}

<img class='custom_class' src='{% barcode "12345678" barcode_class="Code39" %}>

You can also pass further python-barcode supported parameters as well:

{% load barcode %}

<img class='barcode' src='{% barcode part.IPN barcode_class="Code128" write_text=0 background="red" %}'>

QR-Code¶

qrcode

Two dimensional QR codes are generated using the qrcode library.

To render a QR code, use the qrcode template tag:

Parameters:

Name	Type	Description	Default
`data`	`str`	Data to encode	required

Other Parameters:

Name	Type	Description
`version`	`int`	QR code version, (None to auto detect) (default = None)
`error_correction`	`str`	Error correction level (L: 7%, M: 15%, Q: 25%, H: 30%) (default = 'M')
`box_size`	`int`	pixel dimensions for one black square pixel in the QR code (default = 20)
`border`	`int`	count white QR square pixels around the qr code, needed as padding (default = 1)
`optimize`	`int`	data will be split into multiple chunks of at least this length using different modes (text, alphanumeric, binary) to optimize the QR code size. Set to `0` to disable. (default = 1)
`format`	`str`	Image format (default = 'PNG')
`fill_color`	`str`	Fill color (default = "black")
`back_color`	`str`	Background color (default = "white")

Returns:

Name	Type	Description
`image`	`str`	base64 encoded image data

Example¶

{% extends "label/label_base.html" %}

{% load l10n i18n barcode %}

{% block style %}

.qr {
    position: absolute;
    left: 0mm;
    top: 0mm;
    {% localize off %}
    height: {{ height }}mm;
    width: {{ height }}mm;
    {% endlocalize %}
}

{% endblock style %}

{% block content %}
<img class='qr' src='{% qrcode "Hello world!" fill_color="white" back_color="blue" %}'>
{% endblock content %}

which produces the following output:

Documentation

Refer to the qrcode library documentation for more information

Data Matrix¶

ppf.datamatrix

Data Matrix codes are generated using the ppf.datamatrix library.

Data Matrix Codes provide an alternative to QR codes for encoding data in a two-dimensional matrix. To render a Data Matrix code, use the datamatrix template tag:

Parameters:

Name	Type	Description	Default
`data`	`str`	Data to encode	required

Other Parameters:

Name	Type	Description
`fill_color`	`str`	Foreground color (default = 'black')
`back_color`	`str`	Background color (default = 'white')
`scale`	`float`	Matrix scaling factor (default = 1)
`border`	`int`	Border width (default = 1)

Returns:

Name	Type	Description
`image`	`str`	base64 encoded image data

Example¶

{% extends "label/label_base.html" %}

{% load l10n i18n barcode %}

{% block style %}

.qr {
    position: absolute;
    left: 0mm;
    top: 0mm;
    {% localize off %}
    height: {{ height }}mm;
    width: {{ height }}mm;
    {% endlocalize %}
}

{% endblock style %}

{% block content %}


<img class='qr' src='{% datamatrix "Foo Bar" back_color="yellow" %}'>

{% endblock content %}

which produces the following output: