def test_attribute(self):
# Check we get an error when called with something other than a function.
self.assertRaises(ProgrammingError, attribute, 'not a getter')
self.assertRaises(ProgrammingError, attribute, 123)
self.assertRaises(ProgrammingError, attribute, None)
# Call the decorator with a function.
getter = lambda: None
p = attribute(getter)
# Check we got a property object.
self.assertIsInstance(p, property)
# Check the property object has both setter and getter functions.
self.assertTrue(p.fset)
self.assertTrue(p.fget)
# Pretend we decorated an object.
entity_id = uuid4()
o = VersionedEntity(originator_id=entity_id, originator_version=0)
o.__dict__['_<lambda>'] = 'value1'
# Call the property's getter function.
value = p.fget(o)
self.assertEqual(value, 'value1')
# Call the property's setter function.
p.fset(o, 'value2')
# Check the attribute has changed.
value = p.fget(o)
self.assertEqual(value, 'value2')
# Check the property's getter function isn't the getter function we passed in.
self.assertNotEqual(p.fget, getter)
# Define a class that uses the decorator.
class Aaa(VersionedEntity):
"An event sourced entity."
def __init__(self, a, *args, **kwargs):
super(Aaa, self).__init__(*args, **kwargs)
self._a = a
@attribute
def a(self):
"A mutable event sourced property."
# Instantiate the class and check assigning to the property publishes an event and updates the object state.
published_events = []
subscription = (lambda x: True, lambda x: published_events.append(x))
subscribe(*subscription)
entity_id = uuid4()
try:
aaa = Aaa(originator_id=entity_id, originator_version=1, a=1)
self.assertEqual(aaa.a, 1)
aaa.a = 'value1'
self.assertEqual(aaa.a, 'value1')
finally:
unsubscribe(*subscription)
# Check an event was published.
self.assertEqual(len(published_events), 1)
# Check the published event was an AttributeChanged event, with the expected attribute values.
published_event = published_events[0]
self.assertIsInstance(published_event, AttributeChanged)
self.assertEqual(published_event.name, '_a')
self.assertEqual(published_event.value, 'value1')
self.assertTrue(published_event.originator_version, 1)
self.assertEqual(published_event.originator_id, entity_id)
def test_attribute(self):
# Check we get an error when called with something other than a function.
self.assertRaises(ProgrammingError, attribute, 'not a getter')
self.assertRaises(ProgrammingError, attribute, 123)
self.assertRaises(ProgrammingError, attribute, None)
# Call the decorator with a function.
getter = lambda: None
p = attribute(getter)
# Check we got a property object.
self.assertIsInstance(p, property)
# Check the property object has both setter and getter functions.
self.assertTrue(p.fset)
self.assertTrue(p.fget)
# Pretend we decorated an object.
entity_id = uuid4()
o = VersionedEntity(id=entity_id, __version__=0)
o.__dict__['_<lambda>'] = 'value1'
# Call the property's getter function.
value = p.fget(o)
self.assertEqual(value, 'value1')
# Call the property's setter function.
p.fset(o, 'value2')
# Check the attribute has changed.
value = p.fget(o)
self.assertEqual(value, 'value2')
# Check the property's getter function isn't the getter function we passed in.
self.assertNotEqual(p.fget, getter)
# Define a class that uses the decorator.
class Aaa(VersionedEntity):
"An event sourced entity."
def __init__(self, a, *args, **kwargs):
super(Aaa, self).__init__(*args, **kwargs)
self._a = a
@attribute
def a(self):
"A mutable event sourced property."
# Instantiate the class and check assigning to the property publishes an event and updates the object state.
published_events = []
subscription = (lambda x: True, lambda x: published_events.append(x))
subscribe(*subscription)
entity_id = uuid4()
try:
aaa = Aaa(id=entity_id, __version__=1, a=1)
self.assertEqual(aaa.a, 1)
aaa.a = 'value1'
self.assertEqual(aaa.a, 'value1')
finally:
unsubscribe(*subscription)
# Check an event was published.
self.assertEqual(len(published_events), 1)
# Check the published event was an AttributeChanged event, with the expected attribute values.
published_event = published_events[0]
self.assertIsInstance(published_event, AttributeChanged)
self.assertEqual(published_event.name, '_a')
self.assertEqual(published_event.value, 'value1')
self.assertTrue(published_event.originator_version, 1)
self.assertEqual(published_event.originator_id, entity_id)