def unregister_class(alias):
"""
Opposite of L{register_class}.
@raise UnknownClassAlias: Unknown alias.
"""
try:
x = CLASS_CACHE[alias]
except KeyError:
raise UnknownClassAlias('Unknown alias %r' % (alias, ))
if not x.anonymous:
del CLASS_CACHE[x.alias]
del CLASS_CACHE[x.klass]
return x
def get_class_alias(klass_or_alias):
"""
Finds the L{ClassAlias} that is registered to C{klass_or_alias}.
If a string is supplied and no related L{ClassAlias} is found, the alias is
loaded via L{load_class}.
@raise UnknownClassAlias: Unknown alias
"""
if isinstance(klass_or_alias, python.str_types):
try:
return CLASS_CACHE[klass_or_alias]
except KeyError:
return load_class(klass_or_alias)
try:
return CLASS_CACHE[klass_or_alias]
except KeyError:
raise UnknownClassAlias('Unknown alias for %r' % (klass_or_alias, ))
def flex_loader(alias):
"""
Loader for L{Flex<pyamf.flex>} framework compatibility classes.
@raise UnknownClassAlias: Trying to load an unknown Flex compatibility class.
"""
if not alias.startswith('flex.'):
return
try:
if alias.startswith('flex.messaging.messages'):
import pyamf.flex.messaging
elif alias.startswith('flex.messaging.io'):
import pyamf.flex
elif alias.startswith('flex.data.messages'):
import pyamf.flex.data
return CLASS_CACHE[alias]
except KeyError:
raise UnknownClassAlias(alias)
def load_class(alias):
"""
Finds the class registered to the alias.
The search is done in order:
1. Checks if the class name has been registered via L{register_class}
or L{register_package}.
2. Checks all functions registered via L{register_class_loader}.
3. Attempts to load the class via standard module loading techniques.
@param alias: The class name.
@type alias: C{string}
@raise UnknownClassAlias: The C{alias} was not found.
@raise TypeError: Expecting class type or L{ClassAlias} from loader.
@return: Class registered to the alias.
@rtype: C{classobj}
"""
# Try the CLASS_CACHE first
try:
return CLASS_CACHE[alias]
except KeyError:
pass
for loader in CLASS_LOADERS:
klass = loader(alias)
if klass is None:
continue
if isinstance(klass, python.class_types):
return register_class(klass, alias)
elif isinstance(klass, ClassAlias):
CLASS_CACHE[klass.alias] = klass
CLASS_CACHE[klass.klass] = klass
return klass
raise TypeError("Expecting class object or ClassAlias from loader")
mod_class = alias.split('.')
if mod_class:
module = '.'.join(mod_class[:-1])
klass = mod_class[-1]
try:
module = util.get_module(module)
except (ImportError, AttributeError):
pass
else:
klass = getattr(module, klass)
if isinstance(klass, python.class_types):
return register_class(klass, alias)
elif isinstance(klass, ClassAlias):
CLASS_CACHE[klass.alias] = klass
CLASS_CACHE[klass.klass] = klass
return klass.klass
else:
raise TypeError(
"Expecting class type or ClassAlias from loader")
# All available methods for finding the class have been exhausted
raise UnknownClassAlias("Unknown alias for %r" % (alias, ))
