def resolve(cls):
if not cls._resolved:
try:
cls._resolved = globals()[cls._referenced]
except KeyError:
raise ModelDefinitionError('Undefined Model "{}"'.format(cls._referenced))
return cls._resolved
def __new__(mcs, name, bases, attrs):
klass = super(ModelMeta, mcs).__new__(mcs, name, bases, attrs)
model_ref_cls = globals().get('_ModelReference')
if name == '_ModelReference' or (model_ref_cls
and issubclass(klass, model_ref_cls)):
setattr(sys.modules[mcs.__module__], name, klass)
return klass
# Every model has to be bound to a topic except for the Model base class
# Since it is using this class as meta class, we will dynamically get the class object from the globals
model_cls = globals().get('Model')
if model_cls and issubclass(klass, model_cls):
topic = getattr(klass, 'topic', None)
if not topic or not issubclass(topic, Topic):
raise ModelDefinitionError(
'Missing topic in Model {}'.format(name))
topic.messages = tuple(set(topic.messages + (klass, )))
kls_attrs = (getattr(klass, 'fields', None) or {}).copy()
kls_attrs.update({
name: value
for name, value in attrs.items()
if isinstance(value, fields.Field)
})
klass.fields = kls_attrs.copy()
setattr(sys.modules[mcs.__module__], name, klass)
return klass
def __new__(mcs, name, bases, attrs):
klass = super(ModelMeta, mcs).__new__(mcs, name, bases, attrs)
# Every model has to be bound to a topic
if klass.__name__ != 'Model' and issubclass(klass, ModelMeta):
topic = getattr(klass, 'topic', None)
if not topic or not issubclass(topic, Topic):
raise ModelDefinitionError(
'Missing topic in Model {}'.format(name))
topic.messages = tuple(set(topic.messages + (klass, )))
kls_attrs = {
name: value
for name, value in attrs.items()
if isinstance(value, fields.Field)
}
klass.fields = kls_attrs.copy()
setattr(sys.modules[mcs.__module__], name, klass)
return klass
