Skip to main content

Zope Container

Project description

This package define interfaces of container components, and provides sample container implementations such as a BTreeContainer and OrderedContainer.

Detailed Documentation

Containment constraints

Containment constraints allow us to express restrictions on the types of items that can be placed in containers or on the types of containers an item can be placed in. We express these constraints in interfaces. Let’s define some container and item interfaces:

>>> from zope.app.container.interfaces import IContainer, IContained
>>> from zope.app.container.constraints import containers, contains
>>> class IBuddyFolder(IContainer):
...     contains('.IBuddy')

In this example, we used the contains function to declare that objects that provide IBuddyFolder can only contain items that provide IBuddy. Note that we used a string containing a dotted name for the IBuddy interface. This is because IBuddy hasn’t been defined yet. When we define IBuddy, we can use IBuddyFolder directly:

>>> class IBuddy(IContained):
...     containers(IBuddyFolder)

Now, with these interfaces in place, we can define Buddy and BuddyFolder classes and verify that we can put buddies in buddy folders:

>>> from zope import interface
>>> class Buddy:
...     interface.implements(IBuddy)
>>> class BuddyFolder:
...     interface.implements(IBuddyFolder)
>>> from zope.app.container.constraints import checkObject, checkFactory
>>> from zope.component.factory import Factory
>>> checkObject(BuddyFolder(), 'x', Buddy())
>>> checkFactory(BuddyFolder(), 'x', Factory(Buddy))
True

If we try to use other containers or folders, we’ll get errors:

>>> class Container:
...     interface.implements(IContainer)
>>> class Contained:
...     interface.implements(IContained)
>>> checkObject(Container(), 'x', Buddy())
... # doctest: +ELLIPSIS
Traceback (most recent call last):
InvalidContainerType: ...
>>> checkFactory(Container(), 'x', Factory(Buddy))
False
>>> checkObject(BuddyFolder(), 'x', Contained())
... # doctest: +ELLIPSIS
Traceback (most recent call last):
InvalidItemType: ...
>>> checkFactory(BuddyFolder(), 'x', Factory(Contained))
False

In the example, we defined the container first and then the items. We could have defined these in the opposite order:

>>> class IContact(IContained):
...     containers('.IContacts')
>>> class IContacts(IContainer):
...     contains(IContact)
>>> class Contact:
...     interface.implements(IContact)
>>> class Contacts:
...     interface.implements(IContacts)
>>> checkObject(Contacts(), 'x', Contact())
>>> checkFactory(Contacts(), 'x', Factory(Contact))
True
>>> checkObject(Contacts(), 'x', Buddy())
... # doctest: +ELLIPSIS
Traceback (most recent call last):
InvalidItemType: ...
>>> checkFactory(Contacts(), 'x', Factory(Buddy))
False

CHANGES

3.6.1 (2008-10-15)

3.6.0 (2008-05-06)

  • Added an IBTreeContainer interface that allows an argument to the items, keys, and values methods with the same semantics as for a BTree object. The extended interface is implemented by the BTreeContainer class.

3.5 (2007-10-11)

  • Updated bootstrap script to current version.

  • Store length of BTreeContainer in its own Length object for faster __len__ implementation of huge containers.

  • Send IObjectModifiedEvent when changing the title through the @@contents.html view. This fixes https://bugs.edge.launchpad.net/zope3/+bug/98483.

  • Resolve ZopeSecurityPolicy and IRolePermissionManager deprecation warning.

3.4 (2007-04-22)

  • Initial release as a separate project, corresponds to zope.app.container from Zope 3.4.0a1.

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

zope.app.container-3.6.1.tar.gz (117.5 kB view hashes)

Uploaded Source

Built Distributions

zope.app.container-3.6.1-py2.5-win32.egg (184.2 kB view hashes)

Uploaded Source

zope.app.container-3.6.1-py2.4-win32.egg (186.2 kB view hashes)

Uploaded Source

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page