jbalogh/jingo

.. module:: jingo

Jingo

Jingo is an adapter for using Jinja2 templates within Django.

Jingo is DEPRECATED

In version 1.8, Django added support for multiple template engines, and provided a Jinja2 backend. The django-jinja project leverages that to support Jinja2, while Jingo does not.

django-jinja is recommended for new projects. Jingo >=0.8 supports Django 1.8, but it will not be maintained beyond version 0.9, and will not support Django 1.9 or above. If you're already using Jingo, and not ready to make the switch, Jingo should continue to work for now, though not without some effort.

0.9 will be the last release of Jingo, unless a new maintainer comes along with a new direction.

As of 0.9, Jingo's built-in helpers are provided via a Jinja2 extension to simplify moving away from Jingo. The entire jingo/ext.py file can be copied into another project, or referenced as 'jingo.ext.JingoExtension'. Used in this way, Jingo plays nicely with django-jinja (and theoretically Django's built-in Jinja2 backend).

Usage

When configured properly (see Settings below) you can render Jinja2 templates in your view the same way you'd render Django templates:

from django.shortcuts import render


def my_view(request):
    context = dict(user_ids=(1, 2, 3, 4))
    return render(request, 'users/search.html', context)

Settings

You'll want to use Django to use jingo's template loader. In settings.py:

TEMPLATE_LOADERS = (
    'jingo.Loader',
    'django.template.loaders.filesystem.Loader',
    'django.template.loaders.app_directories.Loader',
)

This will let you use django.shortcuts.render or django.shortcuts.render_to_response.

You can optionally specify which filename patterns to consider Jinja2 templates:

JINGO_INCLUDE_PATTERN = r'\.jinja2'  # use any regular expression here

This will consider every template file that contains the substring .jinja2 to be a Jinja2 file (unless it's in a module explicitly excluded, see below).

And finally you may have apps that do not use Jinja2, these must be excluded from the loader:

JINGO_EXCLUDE_APPS = ('debug_toolbar',)

If a template path begins with debug_toolbar, the Jinja loader will raise a TemplateDoesNotExist exception. This causes Django to move onto the next loader in TEMPLATE_LOADERS to find a template - in this case, django.template.loaders.filesystem.Loader.

The default is in jingo.EXCLUDE_APPS:

EXCLUDE_APPS = (
    'admin',
    'admindocs',
    'registration',
    'context_processors',
)

.. versionchanged:: 0.6.2
   Added ``context_processors`` application.

If you want to configure the Jinja environment, use JINJA_CONFIG in settings.py. It can be a dict or a function that returns a dict.

JINJA_CONFIG = {'autoescape': False}

or:

def JINJA_CONFIG():
    return {'the_answer': 41 + 1}

If you set the extensions key in the configuration, you must include jingo.ext.JingoExtension to get Jingo's built-in template helpers (see below).

Template Helpers

Instead of template tags, Jinja encourages you to add functions and filters to the templating environment. In jingo, we call these helpers. When the Jinja environment is initialized, jingo will try to open a helpers.py file from every app in INSTALLED_APPS. Two decorators are provided to ease the environment extension:

.. function:: jingo.register.filter

    Adds the decorated function to Jinja's filter library.

.. function:: jingo.register.function

    Adds the decorated function to Jinja's global namespace.

Default Helpers

Helpers are available in all templates automatically, without any extra loading. See jingo/ext.py for their definitions.

Template Environment

A single Jinja Environment is created for use in all templates. This is available via jingo.get_env() if you need to work with the Environment.

Localization

Since we all love L10n, let's see what it looks like in Jinja templates:

<h2>{{ _('Reviews for {0}')|f(addon.name) }}</h2>

The simple way is to use the familiar underscore and string within a {{ }} moustache block. f is an interpolation filter documented below. Sphinx could create a link if I knew how to do that.

The other method uses Jinja's trans tag:

{% trans user=review.user|user_link, date=review.created|datetime %}
    by {{ user }} on {{ date }}
{% endtrans %}

trans is nice when you have a lot of text or want to inject some variables directly. Both methods are useful, pick the one that makes you happy.

Forms

Django marks its form HTML "safe" according to its own rules, which Jinja2 does not recognize.

This monkeypatches Django to support the __html__ protocol used in Jinja2 templates. Form, BoundField, ErrorList, and other form objects that render HTML through their __unicode__ method are extended with __html__ so they can be rendered in Jinja2 templates without adding |safe.

Call the patch() function to execute the patch. It must be called before django.forms is imported for the conditional_escape patch to work properly. The root URLconf is the recommended location for calling patch().

Usage:

import jingo.monkey
jingo.monkey.patch()

Testing

To run the test suite, you need to define DJANGO_SETTINGS_MODULE first:

$ export DJANGO_SETTINGS_MODULE="fake_settings"
$ nosetests

or simply run:

$ python run_tests.py

To test on all supported versions of Python and Django:

$ pip install tox
$ tox