Local Extensions¶
New in Cookiecutter X.x
A template may extend the Cookiecutter environment with local extensions. These can be part of the template itself, providing it with more sophisticated custom tags and filters.
To do so, a template author must specify the required extensions in cookiecutter.json
as follows:
{
"project_slug": "Foobar",
"year": "{% now 'utc', '%Y' %}",
"_extensions": ["local_extensions.FoobarExtension"]
}
This example assumes that a local_extensions
folder (python module) exists in the template root.
It will contain a main.py
file, containing the following (for instance):
# -*- coding: utf-8 -*-
from jinja2.ext import Extension
class FoobarExtension(Extension):
def __init__(self, environment):
super(FoobarExtension, self).__init__(environment)
environment.filters['foobar'] = lambda v: v * 2
This will register the foobar
filter for the template.
For many cases, this will be unneccessarily complicated.
It’s likely that we’d only want to register a single function as a filter. For this, we can use the simple_filter
decorator:
{
"project_slug": "Foobar",
"year": "{% now 'utc', '%Y' %}",
"_extensions": ["local_extensions.simplefilterextension"]
}
# -*- coding: utf-8 -*-
from cookiecutter.utils import simple_filter
@simple_filter
def simplefilterextension(v):
return v * 2
This snippet will achieve the exact same result as the previous one.