Package: zope.site
zope.siteThis package provides a local and persistent site manager
implementation, so that one can register local utilities and
adapters. It uses local adapter registries for its adapter and utility
registry. The module also provides some facilities to organize the
local software and ensures the correct behavior inside the ZODB.Documentation is hosted athttps://zopesite.readthedocs.ioSites and Local Site ManagersThis is an introduction of location-based component architecture.Creating and Accessing SitesSitesare used to provide custom component setups for parts of your
application or web site. Every folder:>>> from zope.site import folder
>>> myfolder = folder.rootFolder()has the potential to become a site:>>> from zope.component.interfaces import ISite, IPossibleSite
>>> IPossibleSite.providedBy(myfolder)
Truebut is not yet one:>>> ISite.providedBy(myfolder)
FalseIf you would like your custom content component to be able to become a site,
you can use theSiteManagerContainermix-in class:>>> from zope import site
>>> class MyContentComponent(site.SiteManagerContainer):
...     pass>>> myContent = MyContentComponent()
>>> IPossibleSite.providedBy(myContent)
True
>>> ISite.providedBy(myContent)
FalseTo convert a possible site to a real site, we have to provide a site manager:>>> sm = site.LocalSiteManager(myfolder)
>>> myfolder.setSiteManager(sm)
>>> ISite.providedBy(myfolder)
True
>>> myfolder.getSiteManager() is sm
TrueNote that an event is generated when a local site manager is created:>>> from zope.component.eventtesting import getEvents
>>> from zope.site.interfaces import INewLocalSite
>>> [event] = getEvents(INewLocalSite)
>>> event.manager is sm
TrueIf one tries to set a bogus site manager, aValueErrorwill be raised:>>> myfolder2 = folder.Folder()
>>> myfolder2.setSiteManager(object)
Traceback (most recent call last):
...
ValueError: setSiteManager requires an IComponentLookupIf the possible site has been changed to a site already, aTypeErroris raised when one attempts to add a new site manager:>>> myfolder.setSiteManager(site.LocalSiteManager(myfolder))
Traceback (most recent call last):
...
TypeError: Already a siteThere is also an adapter you can use to get the next site manager from any
location:>>> myfolder['mysubfolder'] = folder.Folder()
>>> import zope.interface.interfaces
>>> zope.interface.interfaces.IComponentLookup(myfolder['mysubfolder']) is sm
TrueIf the location passed is a site, the site manager of that site is returned:>>> zope.interface.interfaces.IComponentLookup(myfolder) is sm
TrueUsing the Site ManagerA site manager contains severalsite management folders, which are used to
logically organize the software. When a site manager is initialized, a default
site management folder is created:>>> sm = myfolder.getSiteManager()
>>> default = sm['default']
>>> default.__class__
<class 'zope.site.site.SiteManagementFolder'>However, you can tell not to create the default site manager folder on
LocalSiteManager creation:>>> nodefault = site.LocalSiteManager(myfolder, default_folder=False)
>>> 'default' in nodefault
FalseAlso, note that when creating LocalSiteManager, its __parent__ is set to
site that was passed to constructor and the __name__ is set to ++etc++site.>>> nodefault.__parent__ is myfolder
True
>>> nodefault.__name__ == '++etc++site'
TrueYou can easily create a new site management folder:>>> sm['mySMF'] = site.SiteManagementFolder()
>>> sm['mySMF'].__class__
<class 'zope.site.site.SiteManagementFolder'>Once you have your site management folder – let’s use the default one – we
can register some components. Let’s start with a utility (we define it
in a__module__that can be pickled):>>> import zope.interface
>>> __name__ = 'zope.site.tests'
>>> class IMyUtility(zope.interface.Interface):
...     pass>>> import persistent
>>> from zope.container.contained import Contained
>>> @zope.interface.implementer(IMyUtility)
... class MyUtility(persistent.Persistent, Contained):
...     def __init__(self, title):
...         self.title = title
...     def __repr__(self):
...         return "%s('%s')" %(self.__class__.__name__, self.title)Now we can create an instance of our utility and put it in the site
management folder and register it:>>> myutil = MyUtility('My custom utility')
>>> default['myutil'] = myutil
>>> sm.registerUtility(myutil, IMyUtility, 'u1')Now we can ask the site manager for the utility:>>> sm.queryUtility(IMyUtility, 'u1')
MyUtility('My custom utility')Of course, the local site manager has also access to the global component
registrations:>>> gutil = MyUtility('Global Utility')
>>> from zope.component import getGlobalSiteManager
>>> gsm = getGlobalSiteManager()
>>> gsm.registerUtility(gutil, IMyUtility, 'gutil')>>> sm.queryUtility(IMyUtility, 'gutil')
MyUtility('Global Utility')Next let’s see whether we can also successfully register an adapter as
well. Here the adapter will provide the size of a file:>>> class IFile(zope.interface.Interface):
...     pass>>> class ISized(zope.interface.Interface):
...     pass>>> @zope.interface.implementer(IFile)
... class File(object):
...     pass>>> @zope.interface.implementer(ISized)
... class FileSize(object):
...     def __init__(self, context):
...         self.context = contextNow that we have the adapter we need to register it:>>> sm.registerAdapter(FileSize, [IFile])Finally, we can get the adapter for a file:>>> file = File()
>>> size = sm.queryAdapter(file, ISized, name='')
>>> isinstance(size, FileSize)
True
>>> size.context is file
TrueBy the way, once you set a site>>> from zope.component import hooks
>>> hooks.setSite(myfolder)you can simply use the zope.component’sgetSiteManager()method to get
the nearest site manager:>>> from zope.component import getSiteManager
>>> getSiteManager() is sm
TrueThis also means that you can simply use zope.component to look up your utility>>> from zope.component import getUtility
>>> getUtility(IMyUtility, 'gutil')
MyUtility('Global Utility')or the adapter via the interface’s__call__method:>>> size = ISized(file)
>>> isinstance(size, FileSize)
True
>>> size.context is file
TrueMultiple SitesUntil now we have only dealt with one local and the global site. But things
really become interesting, once we have multiple sites. We can override other
local configuration.This behaviour uses the notion of location, therefore we need to configure the
zope.location package first:>>> import zope.configuration.xmlconfig
>>> _  = zope.configuration.xmlconfig.string("""
... <configure xmlns="http://namespaces.zope.org/zope">
...   <include package="zope.component" file="meta.zcml"/>
...   <include package="zope.location" />
... </configure>
... """)Let’s now create a new folder calledfolder11, add it tomyfolderand make
it a site:>>> myfolder11 = folder.Folder()
>>> myfolder['myfolder11'] = myfolder11
>>> myfolder11.setSiteManager(site.LocalSiteManager(myfolder11))
>>> sm11 = myfolder11.getSiteManager()If we ask the second site manager for its next, we get>>> sm11.__bases__ == (sm, )
Trueand the first site manager should have the folling sub manager:>>> sm.subs == (sm11,)
TrueIf we now register a second utility with the same name and interface with the
new site manager folder,>>> default11 = sm11['default']
>>> myutil11 = MyUtility('Utility, uno & uno')
>>> default11['myutil'] = myutil11>>> sm11.registerUtility(myutil11, IMyUtility, 'u1')then it will will be available in the second site manager>>> sm11.queryUtility(IMyUtility, 'u1')
MyUtility('Utility, uno & uno')but not in the first one:>>> sm.queryUtility(IMyUtility, 'u1')
MyUtility('My custom utility')It is also interesting to look at the use cases of moving and copying a
site. To do that we create a second root folder and make it a site, so that
site hierarchy is as follows:_____ global site _____
        /                       \
    myfolder                 myfolder2
        |
    myfolder11


>>> myfolder2 = folder.rootFolder()
>>> myfolder2.setSiteManager(site.LocalSiteManager(myfolder2))Before we can move or copy sites, we need to register two event subscribers
that manage the wiring of site managers after moving or copying:>>> import zope.lifecycleevent.interfaces
>>> gsm.registerHandler(
...    site.changeSiteConfigurationAfterMove,
...    (ISite, zope.lifecycleevent.interfaces.IObjectMovedEvent),
...    )We only have to register one event listener, since the copy action causes anIObjectAddedEventto be created, which is just a special type ofIObjectMovedEvent.First, make sure that everything is setup correctly in the first place:>>> myfolder11.getSiteManager().__bases__ == (myfolder.getSiteManager(), )
True
>>> myfolder.getSiteManager().subs[0] is myfolder11.getSiteManager()
True
>>> myfolder2.getSiteManager().subs
()Let’s now movemyfolder11frommyfoldertomyfolder2:>>> myfolder2['myfolder21'] = myfolder11
>>> del myfolder['myfolder11']Now the next site manager formyfolder11’s site manager should have changed:>>> myfolder21 = myfolder11
>>> myfolder21.getSiteManager().__bases__ == (myfolder2.getSiteManager(), )
True
>>> myfolder2.getSiteManager().subs[0] is myfolder21.getSiteManager()
True
>>> myfolder.getSiteManager().subs
()Make sure that our interfaces and classes are picklable:>>> import sys
>>> sys.modules['zope.site.tests'].IMyUtility = IMyUtility
>>> sys.modules['zope.site.tests'].MyUtility = MyUtility>>> from pickle import dumps, loads
>>> data = dumps(myfolder2['myfolder21'])
>>> myfolder['myfolder11'] = loads(data)>>> myfolder11 = myfolder['myfolder11']
>>> myfolder11.getSiteManager().__bases__ == (myfolder.getSiteManager(), )
True
>>> myfolder.getSiteManager().subs[0] is myfolder11.getSiteManager()
True
>>> myfolder2.getSiteManager().subs[0] is myfolder21.getSiteManager()
TrueFinally, let’s check that everything works fine when our folder is moved
to the folder that doesn’t contain any site manager. Our folder’s
sitemanager’s bases should be set to global site manager.>>> myfolder11.getSiteManager().__bases__ == (myfolder.getSiteManager(), )
True>>> nosm = folder.Folder()
>>> nosm['root'] = myfolder11
>>> myfolder11.getSiteManager().__bases__ == (gsm, )
TrueDeleting a site unregisters its site manger from its parent site manager:>>> del myfolder2['myfolder21']
>>> myfolder2.getSiteManager().subs
()The removed site manager now has no bases:>>> myfolder21.getSiteManager().__bases__
()Changes5.0 (2023-06-30)Drop support for Python 2.7, 3.5, 3.6.Add support for Python 3.11.4.6.1 (2022-09-02)Fix more deprecation warnings.4.6 (2022-08-23)Add support for Python 3.9, 3.10.Fix deprecation warning.4.5.0 (2021-03-04)Fix the interface definition ofIRootFolderto giveIRoothigher priority than the folder and container interfaces. This is
what is usually expected, but not what the code defined. Commonly,
in the past, this problem was hidden because the factory functionrootFolder()re-arranged the interfaces to putIRootat the
front. Under zope.interface 5’s C3 resolution order, however, this
rearrangement was not taking place; thus, looking up adapters for arootFolder()object was likely to find adapters forIItemContainerinstead of adapters forIRootas intended.With this change, users ofrootFolder()should notice no changes
compared with zope.interface 4. Code that has classes defined to
implementIRootFolderdirectly, though, may notice a different
resolution order on those objects (consistent with whatrootFolder()generates).Seeissue 17.4.4.0 (2020-09-10)On removal of a site, clear the bases of its site manager. This fixes a reference leak
from a parent site manager. Seeissue 1.4.3.0 (2020-04-01)Add support for Python 3.8.Drop support for Python 3.4.Drop support for the deprecatedpython setup.py testcommand.Fix tests with zope.interface 5.0. Seeissue 12.4.2.2 (2018-10-19)Fix moreDeprecationWarnings. Seeissue 10.4.2.1 (2018-10-11)Use current import location forUtilityRegistrationandIUtilityRegistrationclasses to avoidDeprecationWarning.4.2.0 (2018-10-09)Add support for Python 3.7.4.1.0 (2017-08-08)Add support for Python 3.5 and 3.6.Drop support for Python 2.6 and 3.3.Deprecatezope.site.hooks.*,zope.site.site.setSite,zope.site.next.getNextUtilityandzope.site.next.queryNextUtilitywithzope.deprecation.  These will be removed in version 5.0.
They all have replacements inzope.component.Added implementation for _p_repr in LocalSiteManager. For further
information seeissue 8.Reach 100% test coverage and ensure we remain there.4.0.0 (2014-12-24)Add support for PyPy.Add support for Python 3.4.Add support for testing on Travis.4.0.0a1 (2013-02-20)Added support for Python 3.3.Replaced deprecatedzope.interface.implementsusage with equivalentzope.interface.implementerdecorator.Dropped support for Python 2.4 and 2.5.Include zcml dependencies in configure.zcml, added tests for zcml.3.9.2 (2010-09-25)Added not declared, but needed test dependency onzope.testing.3.9.1 (2010-04-30)Removed use of ‘zope.testing.doctest’ in favor of stdlib’s ‘doctest.Removed use of ‘zope.testing.doctestunit’ in favor of stdlib’s ‘doctest.3.9.0 (2009-12-29)Avoid a test dependency on zope.copypastemove by testing the correct
persistent behavior of a site manager using the normal pickle module.3.8.0 (2009-12-15)Removed functional testing setup and dependency on zope.app.testing.3.7.1 (2009-11-18)Moved the zope.site.hooks functionality to zope.component.hooks as it isn’t
actually dealing with zope.site’s concept of a site.Import ISite and IPossibleSite from zope.component after they were moved
there from zope.location.3.7.0 (2009-09-29)Cleaned up the undeclared dependency on zope.app.publication by moving the
two relevant subscriber registrations and their tests to that package.Dropped the dependency on zope.traversing which was only used to access
zope.location functionality. Configure zope.location for some tests.Demoted zope.configuration to a testing dependency.3.6.4 (2009-09-01)Set __parent__ and __name__ in the LocalSiteManager’s constructor
after calling constructor of its superclasses, so __name__ doesn’t
get overwritten with empty string by the Components constructor.Don’t set __parent__ and __name__ attributes of site manager in
SiteManagerContainer’ssetSiteManagermethod, as they’re
already set for LocalSiteManager. Other site manager implementations
are not required to have those attributes at all, so we’re not
adding them anymore.3.6.3 (2009-07-27)Propagate an ObjectRemovedEvent to the SiteManager upon removal of a
SiteManagerContainer.3.6.2 (2009-07-24)Fixed tests to pass with latest packages.Removed failing test of persistent interfaces, since it did not test
anything in this package and used the deprecatedzodbcodemodule.Fix NameError when callingzope.site.testing.siteSetUp(site=True).ThegetNextUtilityandqueryNextUtilityfunctions was moved tozope.component.  While backward-compatibility imports are provided, it’s
strongly recommended to update your imports.3.6.1 (2009-02-28)Import symbols moved from zope.traversing to zope.location from the new
location.Don’t fail when changing component registry bases while moving ISite
object to non-ISite object.Allow specify whether to create ‘default’ SiteManagementFolder on
initializing LocalSiteManager. Use thedefault_folderargument.Add a containment constraint to the SiteManagementFolder that makes
it only available to be contained in ILocalSiteManagers and other
ISiteManagementFolders.Change package’s mailing list address to zope-dev at zope.org, as
zope3-dev at zope.org is now retired.Remove old unused code. Update package description.3.6.0 (2009-01-31)Use zope.container instead of zope.app.container.3.5.1 (2009-01-27)Extracted from zope.app.component (trunk, 3.5.1 under development)
as part of an effort to clean up dependencies between Zope packages.