mirror of
https://github.com/django/django.git
synced 2025-10-31 09:41:08 +00:00
218 lines
8.1 KiB
Plaintext
218 lines
8.1 KiB
Plaintext
=================================
|
|
Upgrading templates to Django 1.8
|
|
=================================
|
|
|
|
Django's template system was overhauled in Django 1.8 when it gained support
|
|
for multiple template engines. This document complements the :doc:`release
|
|
notes </releases/1.8>` with detailed upgrade instructions on some topics.
|
|
|
|
The :setting:`TEMPLATES` settings
|
|
=================================
|
|
|
|
A new setting was introduced in Django 1.8: :setting:`TEMPLATES`. All existing
|
|
template-related settings were deprecated.
|
|
|
|
During the deprecation period, Django will create a backwards-compatible
|
|
:setting:`TEMPLATES` based on the ``TEMPLATE_*`` settings if you don't define
|
|
it yourself.
|
|
|
|
Here's how to define :setting:`TEMPLATES` in your settings module.
|
|
|
|
If you're using the default value of ``TEMPLATE_LOADERS``, that is, if it
|
|
isn't defined in your settings file or if it's set to::
|
|
|
|
('django.template.loaders.filesystem.Loader',
|
|
'django.template.loaders.app_directories.Loader')
|
|
|
|
then you should define :setting:`TEMPLATES` as follows::
|
|
|
|
TEMPLATES = [
|
|
{
|
|
'BACKEND': 'django.template.backends.django.DjangoTemplates',
|
|
'DIRS': [
|
|
# insert your TEMPLATE_DIRS here
|
|
],
|
|
'APP_DIRS': True,
|
|
'OPTIONS': {
|
|
'context_processors': [
|
|
# Insert your TEMPLATE_CONTEXT_PROCESSORS here or use this
|
|
# list if you haven't customized them:
|
|
'django.contrib.auth.context_processors.auth',
|
|
'django.template.context_processors.debug',
|
|
'django.template.context_processors.i18n',
|
|
'django.template.context_processors.media',
|
|
'django.template.context_processors.static',
|
|
'django.template.context_processors.tz',
|
|
'django.contrib.messages.context_processors.messages',
|
|
],
|
|
},
|
|
},
|
|
]
|
|
|
|
If you aren't using the default value of ``TEMPLATE_LOADERS``, then you should
|
|
define :setting:`TEMPLATES` as follows::
|
|
|
|
TEMPLATES = [
|
|
{
|
|
'BACKEND': 'django.template.backends.django.DjangoTemplates',
|
|
'DIRS': [
|
|
# insert your TEMPLATE_DIRS here
|
|
],
|
|
'OPTIONS': {
|
|
'context_processors': [
|
|
# Insert your TEMPLATE_CONTEXT_PROCESSORS here or use this
|
|
# list if you haven't customized them:
|
|
'django.contrib.auth.context_processors.auth',
|
|
'django.template.context_processors.debug',
|
|
'django.template.context_processors.i18n',
|
|
'django.template.context_processors.media',
|
|
'django.template.context_processors.static',
|
|
'django.template.context_processors.tz',
|
|
'django.contrib.messages.context_processors.messages',
|
|
],
|
|
'loaders': [
|
|
# insert your TEMPLATE_LOADERS here
|
|
]
|
|
},
|
|
},
|
|
]
|
|
|
|
Furthermore you should replace ``django.core.context_processors`` with
|
|
``django.template.context_processors`` in the names of context processors.
|
|
|
|
If your settings module defines ``ALLOWED_INCLUDE_ROOTS`` or
|
|
``TEMPLATE_STRING_IF_INVALID``, include their values under the
|
|
``'allowed_include_roots'`` and ``'string_if_invalid'`` keys in the
|
|
``'OPTIONS'`` dictionary.
|
|
|
|
If it sets ``TEMPLATE_DEBUG`` to a value that differs from :setting:`DEBUG`,
|
|
include that value under the ``'debug'`` key in ``'OPTIONS'``.
|
|
|
|
Once you have defined :setting:`TEMPLATES`, you can safely remove
|
|
``ALLOWED_INCLUDE_ROOTS``, ``TEMPLATE_CONTEXT_PROCESSORS``,
|
|
``TEMPLATE_DEBUG``, ``TEMPLATE_DIRS``, ``TEMPLATE_LOADERS``, and
|
|
``TEMPLATE_STRING_IF_INVALID``.
|
|
|
|
If you are overriding some of these settings in tests, you should override the
|
|
entire :setting:`TEMPLATES` setting instead.
|
|
|
|
:mod:`django.template.loader`
|
|
=============================
|
|
|
|
.. _get_template-upgrade-django-18:
|
|
|
|
:func:`~django.template.loader.get_template` and :func:`~django.template.loader.select_template`
|
|
------------------------------------------------------------------------------------------------
|
|
|
|
In Django 1.8 :func:`~django.template.loader.get_template` and
|
|
:func:`~django.template.loader.select_template` return a backend-dependent
|
|
``Template`` instead of a :class:`django.template.Template`.
|
|
|
|
For example, if :func:`~django.template.loader.get_template` loads a template
|
|
with a :class:`~django.template.backends.django.DjangoTemplates` backend, then
|
|
it returns a ``django.template.backends.django.Template``.
|
|
|
|
``Template`` objects must provide a
|
|
:meth:`~django.template.backends.base.Template.render` method whose signature
|
|
differs slightly from the Django template language's
|
|
:meth:`~django.template.Template.render`.
|
|
|
|
Instead of::
|
|
|
|
from django.template import Context
|
|
from django.template.loader import get_template
|
|
|
|
template = get_template('hello.html')
|
|
html = template.render(Context({'name': 'world'}))
|
|
|
|
You should write::
|
|
|
|
from django.template.loader import get_template
|
|
|
|
template = get_template('hello.html')
|
|
html = template.render({'name': 'world'})
|
|
|
|
And instead of::
|
|
|
|
from django.template import RequestContext
|
|
from django.template.loader import get_template
|
|
|
|
template = get_template('hello.html')
|
|
html = template.render(RequestContext(request, {'name': 'world'}))
|
|
|
|
You should write::
|
|
|
|
from django.template.loader import get_template
|
|
|
|
template = get_template('hello.html')
|
|
html = template.render({'name': 'world'}, request)
|
|
|
|
Passing a :class:`~django.template.Context` or a
|
|
:class:`~django.template.RequestContext` is still possible when the template
|
|
is loaded by a :class:`~django.template.backends.django.DjangoTemplates`
|
|
backend but it's deprecated and won't be supported in Django 1.10.
|
|
|
|
If you're loading a template while you're rendering another template with the
|
|
Django template language and you have access to the current context, for
|
|
instance in the ``render()`` method of a template tag, you can use the current
|
|
:class:`~django.template.Engine` directly. Instead of::
|
|
|
|
from django.template.loader import get_template
|
|
template = get_template('included.html')
|
|
|
|
You can write::
|
|
|
|
template = context.template.engine.get_template('included.html')
|
|
|
|
This will load the template with the current engine without triggering the
|
|
multiple template engines machinery, which is usually the desired behavior.
|
|
Unlike previous solutions, this returns a :class:`django.template.Template`,
|
|
like :func:`~django.template.loader.get_template` used to in Django 1.7 and
|
|
earlier, avoiding all backwards-compatibility problems.
|
|
|
|
``get_template_from_string()``
|
|
------------------------------
|
|
|
|
Private API ``get_template_from_string(template_code)`` was removed in Django
|
|
1.8 because it had no way to choose an engine to compile the template.
|
|
|
|
Three alternatives are available.
|
|
|
|
If you control the project's setting, you can use one of the configured
|
|
engines::
|
|
|
|
from django.template import engines
|
|
|
|
template = engines['django'].from_string(template_code)
|
|
|
|
This returns a backend-dependent ``Template`` object.
|
|
|
|
For trivial templates that don't need context processors nor anything else,
|
|
you can create a bare-bones engine and use its ``from_string()`` method::
|
|
|
|
from django.template import Engine
|
|
|
|
template = Engine().from_string(template_code)
|
|
|
|
This returns a :class:`django.template.Template` because
|
|
:class:`~django.template.Engine` is part of the Django template language's
|
|
APIs. The multiple template engines machinery isn't involved here.
|
|
|
|
Finally, if you have access to the current context, you can use the same trick
|
|
as above::
|
|
|
|
template = context.template.engine.from_string(template_code)
|
|
|
|
``Template()``
|
|
==============
|
|
|
|
To a lesser extent, instantiating a template with ``Template(template_code)``
|
|
suffers from the same issue as ``get_template_from_string()``.
|
|
|
|
It still works when the :setting:`TEMPLATES` setting defines exactly one
|
|
:class:`~django.template.backends.django.DjangoTemplates` backend, but
|
|
pluggable applications can't control this requirement.
|
|
|
|
The last two solutions described in the previous section are recommended in
|
|
that case.
|