Source code for zope.component.interfaces

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"""
Component and Component Architecture Interfaces

The `IComponentArchitecture` and `IComponentRegistrationConvenience` interfaces
are provided by `zope.component` directly.
"""
from zope.interface import Attribute
from zope.interface import Interface

# pylint:disable=inherit-non-class,no-self-argument,no-method-argument

[docs]class IComponentArchitecture(Interface): """The Component Architecture is defined by two key components: Adapters and Utiltities. Both are managed by site managers. All other components build on top of them. """ # Site Manager API def getGlobalSiteManager(): """Return the global site manager. This function should never fail and always return an object that provides `zope.interface.interfaces.IComponents`. """ def getSiteManager(context=None): """Get the nearest site manager in the given context. If *context* is `None`, return the global site manager. If the *context* is not `None`, it is expected that an adapter from the *context* to :mod:`zope.interface.interfaces.IComponentLookup` can be found. If no adapter is found, a `~zope.interface.interfaces.ComponentLookupError` is raised. """ # Utility API def getUtility(interface, name='', context=None): """Get the utility that provides interface Returns the nearest utility to the context that implements the specified interface. If one is not found, raises `~zope.interface.interfaces.ComponentLookupError`. """ def queryUtility(interface, name='', default=None, context=None): """Look for the utility that provides *interface* Returns the nearest utility to the *context* that implements the specified interface. If one is not found, returns *default*. """ def queryNextUtility(context, interface, name='', default=None): """Query for the next available utility. Find the next available utility providing *interface* and having the specified name. If no utility was found, return the specified *default* value. """ def getNextUtility(context, interface, name=''): """Get the next available utility. If no utility was found, a `~zope.interface.interfaces.ComponentLookupError` is raised. """ def getUtilitiesFor(interface, context=None): """Return the utilities that provide an interface An iterable of utility name-value pairs is returned. """ def getAllUtilitiesRegisteredFor(interface, context=None): """Return all registered utilities for an interface This includes overridden utilities. An iterable of utility instances is returned. No names are returned. """ # Adapter API def getAdapter(object, interface=Interface, name=u'', context=None): """Get a named adapter to an interface for an object Returns an adapter that can adapt object to interface. If a matching adapter cannot be found, raises `~zope.interface.interfaces.ComponentLookupError`. """ def getAdapterInContext(object, interface, context): """Get a special adapter to an interface for an object .. note:: This method should only be used if a custom context needs to be provided to provide custom component lookup. Otherwise, call the interface, as in:: interface(object) Returns an adapter that can adapt object to interface. If a matching adapter cannot be found, raises `~zope.interface.interfaces.ComponentLookupError`. If the object has a ``__conform__`` method, this method will be called with the requested interface. If the method returns a non-None value, that value will be returned. Otherwise, if the object already implements the interface, the object will be returned. """ def getMultiAdapter(objects, interface=Interface, name='', context=None): """Look for a multi-adapter to an *interface* for an *objects* Returns a multi-adapter that can adapt *objects* to *interface*. If a matching adapter cannot be found, raises `~zope.interface.interfaces.ComponentLookupError`. The name consisting of an empty string is reserved for unnamed adapters. The unnamed adapter methods will often call the named adapter methods with an empty string for a name. """ def queryAdapter(object, interface=Interface, name=u'', default=None, context=None): """Look for a named adapter to an interface for an object Returns an adapter that can adapt object to interface. If a matching adapter cannot be found, returns the default. """ def queryAdapterInContext(object, interface, context, default=None): """ Look for a special adapter to an interface for an object .. note:: This method should only be used if a custom context needs to be provided to provide custom component lookup. Otherwise, call the interface, as in:: interface(object, default) Returns an adapter that can adapt object to interface. If a matching adapter cannot be found, returns the default. If the object has a ``__conform__`` method, this method will be called with the requested interface. If the method returns a non-None value, that value will be returned. Otherwise, if the object already implements the interface, the object will be returned. """ def queryMultiAdapter(objects, interface=Interface, name=u'', default=None, context=None): """Look for a multi-adapter to an interface for objects Returns a multi-adapter that can adapt objects to interface. If a matching adapter cannot be found, returns the default. The name consisting of an empty string is reserved for unnamed adapters. The unnamed adapter methods will often call the named adapter methods with an empty string for a name. """ def getAdapters(objects, provided, context=None): """ Look for all matching adapters to a provided interface for objects Return a list of adapters that match. If an adapter is named, only the most specific adapter of a given name is returned. """ def subscribers(required, provided, context=None): """Get subscribers Subscribers are returned that provide the provided interface and that depend on and are computed from the sequence of required objects. """ def handle(*objects): """Call all of the handlers for the given objects Handlers are subscription adapter factories that don't produce anything. They do all of their work when called. Handlers are typically used to handle events. """ def adapts(*interfaces): """ Declare that a class adapts the given interfaces. This function can only be used in a class definition. (TODO, allow classes to be passed as well as interfaces.) """ # Factory service def createObject(factory_name, *args, **kwargs): """Create an object using a factory Finds the named factory in the current site and calls it with the given arguments. If a matching factory cannot be found raises `~zope.interface.interfaces.ComponentLookupError`. Returns the created object. A context keyword argument can be provided to cause the factory to be looked up in a location other than the current site. (Of course, this means that it is impossible to pass a keyword argument named "context" to the factory. """ def getFactoryInterfaces(name, context=None): """Get interfaces implemented by a factory Finds the factory of the given name that is nearest to the context, and returns the interface or interface tuple that object instances created by the named factory will implement. """ def getFactoriesFor(interface, context=None): """Return a tuple (name, factory) of registered factories that create objects which implement the given interface. """
[docs]class IRegistry(Interface): """Object that supports component registry """ def registrations(): """Return an iterable of component registrations """
[docs]class IComponentRegistrationConvenience(Interface): """API for registering components. .. caution:: This API should only be used from test or application-setup code. This api shouldn't be used by regular library modules, as component registration is a configuration activity. """ def provideUtility(component, provides=None, name=u''): """Register a utility globally A utility is registered to provide an interface with a name. If a component provides only one interface, then the provides argument can be omitted and the provided interface will be used. (In this case, provides argument can still be provided to provide a less specific interface.) """ def provideAdapter(factory, adapts=None, provides=None, name=u''): """Register an adapter globally An adapter is registered to provide an interface with a name for some number of object types. If a factory implements only one interface, then the provides argument can be omitted and the provided interface will be used. (In this case, a provides argument can still be provided to provide a less specific interface.) If the factory has an adapts declaration, then the adapts argument can be omitted and the declaration will be used. (An adapts argument can be provided to override the declaration.) """ def provideSubscriptionAdapter(factory, adapts=None, provides=None): """Register a subscription adapter A subscription adapter is registered to provide an interface for some number of object types. If a factory implements only one interface, then the provides argument can be omitted and the provided interface will be used. (In this case, a provides argument can still be provided to provide a less specific interface.) If the factory has an adapts declaration, then the adapts argument can be omitted and the declaration will be used. (An adapts argument can be provided to override the declaration.) """ def provideHandler(handler, adapts=None): """Register a handler Handlers are subscription adapter factories that don't produce anything. They do all of their work when called. Handlers are typically used to handle events. If the handler has an adapts declaration, then the adapts argument can be omitted and the declaration will be used. (An adapts argument can be provided to override the declaration.) """
[docs]class IPossibleSite(Interface): """An object that could be a site. """ def setSiteManager(sitemanager): """Sets the site manager for this object. """ def getSiteManager(): """Returns the site manager contained in this object. If there isn't a site manager, raise a component lookup. """
[docs]class ISite(IPossibleSite): """Marker interface to indicate that we have a site"""
[docs]class Misused(Exception): """A component is being used (registered) for the wrong interface."""
[docs]class IFactory(Interface): """A factory is responsible for creating other components.""" title = Attribute("The factory title.") description = Attribute("A brief description of the factory.") def __call__(*args, **kw): """Return an instance of the objects we're a factory for.""" def getInterfaces(): """Get the interfaces implemented by the factory Return the interface(s), as an instance of Implements, that objects created by this factory will implement. If the callable's Implements instance cannot be created, an empty Implements instance is returned. """
# Internal helpers def _inherits_docs(func, iface): doc = iface[func.__name__].__doc__ # By adding the ..seealso:: we get a link from our overview page # to the specific narrative place where the function is described, because # our overview page uses :noindex: doc += "\n .. seealso::" doc += "\n Function `~zope.component.%s` for notes, and " % (func.__name__,) doc += "\n `~zope.component.interfaces.%s` for the defining interface." % (iface.__name__,) doc += "\n" func.__doc__ = doc return func def inherits_arch_docs(func): return _inherits_docs(func, IComponentArchitecture) def inherits_reg_docs(func): return _inherits_docs(func, IComponentRegistrationConvenience)