python-dependency-injector/examples/catalogs/override_declarative.py
2015-11-23 21:46:19 +02:00

49 lines
1.4 KiB
Python

"""Declarative catalog overriding example."""
import collections
from dependency_injector import catalogs
from dependency_injector import providers
# Creating some example classes:
Object1 = collections.namedtuple('Object1', ['arg1', 'arg2'])
Object2 = collections.namedtuple('Object2', ['object1'])
ExtendedObject2 = collections.namedtuple('ExtendedObject2', [])
class Catalog(catalogs.DeclarativeCatalog):
"""Catalog of some providers."""
object1_factory = providers.Factory(Object1,
arg1=1,
arg2=2)
""":type: providers.Provider -> Object1"""
object2_factory = providers.Factory(Object2,
object1=object1_factory)
""":type: providers.Provider -> Object2"""
class AnotherCatalog(catalogs.DeclarativeCatalog):
"""Overriding catalog."""
object2_factory = providers.Factory(ExtendedObject2)
""":type: providers.Provider -> ExtendedObject2"""
# Overriding `Catalog` with `AnotherCatalog`:
Catalog.override(AnotherCatalog)
# Creating some objects using overridden catalog:
object2_1 = Catalog.object2_factory()
object2_2 = Catalog.object2_factory()
# Making some asserts:
assert Catalog.is_overridden
assert object2_1 is not object2_2
assert isinstance(object2_1, ExtendedObject2)
assert isinstance(object2_2, ExtendedObject2)