django-capture-tag

A micro-library to capture output in Django templates.

This can be useful for example to:

  • Repeat page titles in web pages, e.g. for the <title> tag and breadcrumb.
  • Repeat contents for Social Media tags.
  • Reusing thumbnail output in multiple places.
  • Fetch configuration data from extended templates.

Installation

Install the module from PyPI:

pip install django-capture-tag

Add the package to INSTALLED_APPS:

INSTALLED_APPS += (
    'capture_tag',
)

Load the tag in your template:

{% load capture_tags %}

Syntax

The following options are available:

{% capture %}...{% endcapture %}                    # output in {{ capture }}
{% capture silent %}...{% endcapture %}             # output in {{ capture }} only
{% capture as varname %}...{% endcapture %}         # output in {{ varname }}
{% capture as varname silent %}...{% endcapture %}  # output in {{ varname }} only

Example usage

To capture Social Media tags:

{% load capture_tags %}

<head>
    ...

    {# Allow templates to override the page title/description #}
    <meta name="description" content="{% capture as meta_description %}{% block meta-description %}{% endblock %}{% endcapture %}" />
    <title>{% capture as meta_title %}{% block meta-title %}Untitled{% endblock %}{% endcapture %}</title>

    {# display the same value as default, but allow templates to override it. #}
    <meta property="og:description" content="{% block og-description %}{{ meta_description }}{% endblock %}" />
    <meta name="twitter:title" content="{% block twitter-title %}{{ meta_title }}{% endblock %}" />
</head>

Take configuration from extended templates:

# base.html

{% load capture_tags %}

# read once
{% capture as home_url silent %}{% block home_url %}{% url 'app:index' %}{% endblock %}{% endcapture %}

# reuse twice.
<a href="{{ home_url }}" class="btn page-top">Back to home</a>
<a href="{{ home_url }}" class="btn page-bottom">Back to home</a>

# child.html
{% extends "base.html" %}

{% block home_url %}{% url 'user:profile' %}{% endblock %}

Notice

When a value is used only once, this package is not needed. In such case, simply place the {% block .. %} at the proper location where contents is replaced. All common Django template tags support the as variable syntax, such as {% url 'app:index' as home_url %} or {% trans "Foo" as foo_label %}.