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Django @context decorator

django-context-decorator

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django-context-decorator is a Python package for Django removing the need to call super().get_context_data(**kwargs) in nearly every Django view.

You can also read the blog post_ about this package.

Note: If this package is looking unmaintained due to no recent commits, that’s because it’s a tiny package that is feature complete and stable. I see no need to release a new version just to add explicit compatibility with new Django versions, but for as long as Django provides class-based views with a get_context_data method, this package will work with them.

Usage

.. code-block:: python

from django_context_decorator import context from django.utils.functional import cached_property from django.views.generic import TemplateView

class MyView(TemplateView): template_name = 'path/to/template.html'

   @context
   def context_variable(self):
       return 'context value'

   @context
   @property
   def context_property(self):
       return 'context property'

   @context
   @cached_property
   def expensive_context_property(self):
       return 'expensive context property'

Now you'll have access to {{ context_variable }}, {{ context_property }} and {{ expensive_context_property }} in your template.

Please note: While this package works with the @cached_property decorator, please make sure to add the @context decorator above the @cached_property decorator.

This is especially useful when you couple it with inheritance, because it allows you to re-use parent class variables without having to extract them from your context. So you could write a long-form like this:

.. code-block:: python

from django.views.generic import TemplateView


class BaseMixin:

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        ctx['var_from_base_mixin'] = 'var_from_base_mixin'
        return ctx


class View1(BaseMixin, TemplateView):

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        ctx['var_from_view_1'] = 'value_from_view_1'
        return ctx


class View2(View1):

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        ctx['var_from_view_2'] = 'value_from_view_2'
        return ctx

instead like this:

.. code-block:: python

from django.views.generic import TemplateView
from django_context_decorator import context


class BaseMixin:

    @context
    def var_from_base_mixin(self):
        return 'var_from_base_mixin'


class View1(BaseMixin, TemplateView):

    @context
    def var_from_view_1(self):
        return 'value_from_view_1'


class View2(View1):

    @context
    def var_from_view_2(self):
        return 'value_from_view_2'

Development

All code resides in django_context_decorator.py. Tests are collected by pytest from all files starting with test_. To run tests, start a virtual environment, install the dependencies, and run pytest::

pip install django pytest pytest-cov
pytest --cov-report term --cov=django_context_decorator

.. _blog post: https://rixx.de/blog/a-context-decorator-for-django/