Pyramid¶

by Dylan Jay

Heritage of Pyramid¶

Zope => Zope2
Zope2 => Zope3 begat BlueBreem
BlueBreem => ZTK
ZTK => Repoze.BFG (inspired partially by Django)
Repoze.BFG => Pyramid
RoR possibly begat:
- Django
- Pylons
- TurboGears

Who uses it?¶

Karl Project

juice.to

Differences between Pyramid and others¶

Here we go:

Pyramid	Django	Plone
Not opinionated	Opinionated	Structured CMS
Very simple	Simple	Complex
No DB	ORM	Custom DB

Sample view¶

from paste.httpserver import serve
from pyramid.configuration import Configuration
from pyramid.response import Response

def hello_world(context, request):
    return Response('Hello world')

Routes¶

config.add_route('myroute', 'me/{one}')
config.add_view(hello_world, route_name='myroute')

View Callables¶

class MyView(object):
    """ So much more obvious than Django CBVs!"""

    def __init__(self, request):
        # something here I didn't write down

    def __call__(self):
        # why doesn't Django do this?
        raise HttpFound('stuff')

Renderers¶

from pyramid.view import view_config

@view_config(renderer="json")
def hello_worldrequest):
    return dict(content="hello")

One of the renderers is a jinja2 package.

Templates¶

Default: Chameleon (latest version ZPT system)
Can use Jinja2 trivially

Traversal¶

I don’t really care but the Zope fans seem to love it.
Works in that you can get things within things
Some claim you can’t do this in Django - but they are wrong. See MPTT.

View Predicates¶

All described here: http://docs.pylonsproject.org/projects/pyramid_zcml/en/latest/zcml/view.html

Security¶

Seperation of authentication and authorization.
You can easily control the security context of a request
Seems to rely natively on ACL, but you can replace that if you want

# TODO - add example
config.add_view(myview, name='my-view.html', )

See the fun of:

class Blog(object):
    pass

blog = Blog()

blog.__acl__ = [
    (Allow, Everyone, 'view'),
    (Allow, Editors, 'edit'),
    (Allow, Editors, 'delete'),

    ]

Scaffolding¶

Provides a default best practices project layout. Why doesn’t Django do this?!?
Very obvious static directory

How Django does it better¶

Django’s consistent persistence system means easier to cook up reusable apps