django-activeurl

info:	Easy to use active URL highlighting for Django

A demo is available on heroku.com

Features

• automatic highlighting of currently active <a> tags via CSS class
• automatic highlighting of parent <a> tags for menus
• removes boring / hardcoded stuff from your life!

Usage

After loading the template library via

{% load activeurl %}

the following code snippet will be rendered like this if request.full_path() starts with /some_page/:

{% activeurl %}
    <ul>
        <li> <!-- this <li> will render as <li class="active"> -->
            <a href="/some_page/">
                some_page
            </a>
        </li>
        <li>
            <a href="/another_page/">
                another_page
            </a>
        </li>
    </ul>
{% endactiveurl %}

Note: The content of {% activeurl %}…{% endactiveurl %} must have valid root tag (i.e. <ul> or <div>, etc) -- otherwise an exception will be raised.

Installation

Python 2.6, 2.7, 3.2, 3.3, 3.4 and PyPy are supported.

1. Install the stable version using pip:

   pip install django-activeurl
   

   or install the in-development version using pip:

   pip install -e git+git://github.com/hellysmile/django-activeurl#egg=django_activeurl
   

2. In your settings.py add the following:

   INSTALLED_APPS = (
       ...
       'django_activeurl',
       ...
   )
   
   TEMPLATE_CONTEXT_PROCESSORS = (
       ...
       'django.core.context_processors.request',
       ...
   )

3. The lxml library is required and thus additional libraries need to be installed to build it:

   • Ubuntu:

     sudo apt-get install libxml2 libxml2-dev libxslt-dev build-essential python-dev
     sudo ldconfig
     

   • Fedora:

     sudo yum groupinstall 'Development Tools'
     sudo yum install libxslt-devel libxml2 libxml2-devel python-devel
     sudo ldconfig
     

   • MacOS X:

     brew install libxml2 libxslt
     sudo update_dyld_shared_cache -force
     

   • Windows: A pre-built lxml binary can be found here

   • Clouds: There's a 99.99% chance that lxml will build out of the box.

Options

menu ="yes|no" (default: "yes")

Should hierarchical menus be supported? There are two different ways to declare an active status:

• the starts-with logic toggles the active state if request.get_full_path() starts with the content the <a href= attribute.
• the equals logic toggles the active state if request.get_full_path() is identical to the contents of the <a href= attribute.

You might want to use starts-with logic in hierarchical menus/submenus to not only highlight the current position but also every parent positions. So, with request.get_full_path() being /menu/submenu the following snippet will render accordingly:

{% activeurl menu="yes" parent_tag="div" %}
    <div>
        <div>  <!-- This will render as <div class="active"> -->
            <a href="/menu/">
                menu
            </a>
            <div>  <!-- This will also render as <div class="active"> -->
                <a href="/menu/submenu/">
                    submenu
                </a>
            </div>
        </div>
    </div>
{% endactiveurl %}

The equals logic works best for non-hierarchical menus where only those items should be highlighted whose href-attribute perfectly matches request.get_full_path():

{% activeurl menu="no" parent_tag="div" %}
    <div>
        <div>
            <a href="/menu/">
                menu
            </a>
        </div>
        <div>
            <a href="/menu/submenu/">
                submenu
            </a>
        </div>
    </div>
{% endactiveurl %}

parent_tag ="div|li|self|…" (default: "li")

parent_tag defines that a parent element -- and not the <a> tag itself -- should be declared active when there's a match in URLs. When you need to change the CSS class of the <a> tag, just enter "self".

css_class ="<string>" (default: "active")

Defines what CSS class to add to an active element.

Configuration

The default options can be set in settings.py as well:

ACTIVE_URL_KWARGS = {
    'css_class': 'active',
    'parent_tag': 'li',
    'menu': 'yes'
}
ACTIVE_URL_CACHE = True
ACTIVE_URL_CACHE_TIMEOUT = 60 * 60 * 24  # 1 day
ACTIVE_URL_CACHE_PREFIX = 'django_activeurl'

By default django-activeurl will try to retrieve a previously rendered HTML node from Django's caching backend before active URLs are looked for and a new HTML tree is built. You can disable the cache with ACTIVE_URL_CACHE = False.

In addition, ACTIVE_URL_CACHE_TIMEOUT can be used to define a timeout for keys to expire. The default value is one day.

The last configuration option is ACTIVE_URL_CACHE_PREFIX (which is django_activeurl by default) and defines which name to use in Django's caching backend.

Tests

pip install tox
tox

Jinja2

Vanilla Jinja2 configuration:

from jinja2 import Environment

from django_activeurl.ext.django_jinja import ActiveUrl
from django_activeurl.ext.utils import options


env = Environment(
    extensions=[ActiveUrl]
)
env.globals['options'] = options

Except for request, options can be omitted:

{% activeurl options(request, css_class="active", menu="yes", parent_tag="li") %}
    <ul>
        <li>
            <a href="/page/">page</a>
        </li>
        <li>
            <a href="/other_page/">other_page</a>
        </li>
    </ul>
{% endactiveurl %}

If you're using django-jinja, jingo or coffin you need to load the ActiveUrl extension and populate Environment() with options in settings.py.

Background

For building the HTML element tree django-activeurl uses lxml, which is one of the best HTML parsing tools around. More info and benchmarks can be found at habrahabr.ru (in russian). Note that there's no content rebuilding inside the template tag when no active URLs are found, so there's no impact on performance.

Credits

• initializr is used for the example HTML template.
• Simon Whitaker's »Fork me« ribbon is used in the example.