12: Templating With jinja2
¶
We just said Pyramid doesn't prefer one templating language over another. Time
to prove it. Jinja2 is a popular templating system, used in Flask and modeled
after Django's templates. Let's add pyramid_jinja2
, a Pyramid
add-on which enables Jinja2 as a renderer in our Pyramid
applications.
Objectives¶
Show Pyramid's support for different templating systems.
Learn about installing Pyramid add-ons.
Steps¶
In this step let's start by copying the
view_class
step's directory from a few steps ago.cd ..; cp -r view_classes jinja2; cd jinja2
Add
pyramid_jinja2
to our project's dependencies insetup.py
:1from setuptools import setup 2 3# List of dependencies installed via `pip install -e .` 4# by virtue of the Setuptools `install_requires` value below. 5requires = [ 6 'pyramid', 7 'pyramid_chameleon', 8 'pyramid_jinja2', 9 'waitress', 10] 11 12# List of dependencies installed via `pip install -e ".[dev]"` 13# by virtue of the Setuptools `extras_require` value in the Python 14# dictionary below. 15dev_requires = [ 16 'pyramid_debugtoolbar', 17 'pytest', 18 'webtest', 19] 20 21setup( 22 name='tutorial', 23 install_requires=requires, 24 extras_require={ 25 'dev': dev_requires, 26 }, 27 entry_points={ 28 'paste.app_factory': [ 29 'main = tutorial:main' 30 ], 31 }, 32)
Install our project and its newly added dependency.
$VENV/bin/pip install -e .
We need to include
pyramid_jinja2
injinja2/tutorial/__init__.py
:1from pyramid.config import Configurator 2 3 4def main(global_config, **settings): 5 config = Configurator(settings=settings) 6 config.include('pyramid_jinja2') 7 config.add_route('home', '/') 8 config.add_route('hello', '/howdy') 9 config.scan('.views') 10 return config.make_wsgi_app()
Our
jinja2/tutorial/views.py
simply changes itsrenderer
:1from pyramid.view import ( 2 view_config, 3 view_defaults 4 ) 5 6 7@view_defaults(renderer='home.jinja2') 8class TutorialViews: 9 def __init__(self, request): 10 self.request = request 11 12 @view_config(route_name='home') 13 def home(self): 14 return {'name': 'Home View'} 15 16 @view_config(route_name='hello') 17 def hello(self): 18 return {'name': 'Hello View'}
Add
jinja2/tutorial/home.jinja2
as a template:<!DOCTYPE html> <html lang="en"> <head> <title>Quick Tutorial: {{ name }}</title> </head> <body> <h1>Hi {{ name }}</h1> </body> </html>
Now run the tests:
$VENV/bin/pytest tutorial/tests.py -q .... 4 passed in 0.40 seconds
Run your Pyramid application with:
$VENV/bin/pserve development.ini --reload
Open http://localhost:6543/ in your browser.
Analysis¶
Getting a Pyramid add-on into Pyramid is simple. First you use normal Python
package installation tools to install the add-on package into your Python
virtual environment. You then tell Pyramid's configurator to run the setup code
in the add-on. In this case the setup code told Pyramid to make a new
"renderer" available that looked for .jinja2
file extensions.
Our view code stayed largely the same. We simply changed the file extension on the renderer. For the template, the syntax for Chameleon and Jinja2's basic variable insertion is very similar.
Extra credit¶
Our project now depends on
pyramid_jinja2
. We installed that dependency manually. What is another way we could have made the association?We used
config.include
which is an imperative configuration to get the Configurator to loadpyramid_jinja2
's configuration. What is another way we could include it into the config?
See also
Jinja2 homepage, and pyramid_jinja2 Overview