def class_mapper(class_, compile=True):
"""Given a class, return the primary :class:`.Mapper` associated
with the key.
Raises :class:`.UnmappedClassError` if no mapping is configured
on the given class, or :class:`.ArgumentError` if a non-class
object is passed.
"""
try:
class_manager = attributes.manager_of_class(class_)
mapper = class_manager.mapper
except exc.NO_STATE:
if not isinstance(class_, type):
raise sa_exc.ArgumentError("Class object expected, got '%r'." %
class_)
raise exc.UnmappedClassError(class_)
if compile and mapperlib.module._new_mappers:
mapperlib.configure_mappers()
return mapper
def mapper(self):
# raises unless self.mapper has been assigned
raise exc.UnmappedClassError(self.class_)
