Singleton.full_reset() (#391)

* Improve .traverse() typing stubs

* Fix container.reset_singletons()

* Add implementation, tests, and typing stubs

* Add docs and example

* Update changelog

docs/main/changelog.rst

@@ -7,6 +7,13 @@ that were made in every particular version.
 From version 0.7.6 *Dependency Injector* framework strictly 
 follows `Semantic versioning`_
 
+Development version
+-------------------
+- Add ``singleton.full_reset()`` method to reset all underlying singleton providers.
+- Fix ``container.reset_singleton()`` to reset all provider types, not only ``Singleton``.
+- Improve ``container.traverse(types=[...])`` and ``provider.traverse(types=[...])`` typing stubs
+  to return ``types`` -typed iterator.
+
 4.18.0
 ------
 - Add ``container.reset_singleton()`` method to reset container singletons.

docs/providers/singleton.rst

@@ -54,6 +54,14 @@ provider.
    Resetting of the memorized object clears the reference to it. Further object's lifecycle is
    managed by the garbage collector.
 
+Method ``.reset()`` resets only current provider. To reset all dependent singleton providers
+call ``.full_reset()`` method.
+
+.. literalinclude:: ../../examples/providers/singleton_full_resetting.py
+   :language: python
+   :lines: 3-
+   :emphasize-lines: 25
+
 Using singleton with multiple threads
 -------------------------------------
 

examples/providers/singleton_full_resetting.py

@@ -0,0 +1,31 @@
+"""`Singleton` provider full resetting example."""
+
+from dependency_injector import containers, providers
+
+
+class Database:
+    ...
+
+
+class UserService:
+    def __init__(self, db: Database):
+        self.db = db
+
+
+class Container(containers.DeclarativeContainer):
+
+    database = providers.Singleton(Database)
+
+    user_service = providers.Singleton(UserService, db=database)
+
+
+if __name__ == '__main__':
+    container = Container()
+
+    user_service1 = container.user_service()
+
+    container.user_service.full_reset()
+
+    user_service2 = container.user_service()
+    assert user_service2 is not user_service1
+    assert user_service2.db is not user_service1.db

examples/providers/singleton_resetting.py

@@ -9,15 +9,15 @@ class UserService:
 
 class Container(containers.DeclarativeContainer):
 
-    user_service_provider = providers.Singleton(UserService)
+    user_service = providers.Singleton(UserService)
 
 
 if __name__ == '__main__':
     container = Container()
 
-    user_service1 = container.user_service_provider()
+    user_service1 = container.user_service()
 
-    container.user_service_provider.reset()
+    container.user_service.reset()
 
-    user_service2 = container.user_service_provider()
+    user_service2 = container.user_service()
     assert user_service2 is not user_service1

src/dependency_injector/containers.c

@@ -1620,7 +1620,6 @@ static const char __pyx_k_shutdown[] = "shutdown";
 static const char __pyx_k_sub_memo[] = "sub_memo";
 static const char __pyx_k_traverse[] = "traverse";
 static const char __pyx_k_Container[] = "Container";
-static const char __pyx_k_Singleton[] = "Singleton";
 static const char __pyx_k_container[] = "container";
 static const char __pyx_k_decorator[] = "_decorator";
 static const char __pyx_k_iteritems[] = "iteritems";
@@ -1639,6 +1638,7 @@ static const char __pyx_k_isawaitable[] = "isawaitable";
 static const char __pyx_k_IS_CONTAINER[] = "__IS_CONTAINER__";
 static const char __pyx_k_dependencies[] = "dependencies";
 static const char __pyx_k_version_info[] = "version_info";
+static const char __pyx_k_BaseSingleton[] = "BaseSingleton";
 static const char __pyx_k_add_metaclass[] = "add_metaclass";
 static const char __pyx_k_all_providers[] = "all_providers";
 static const char __pyx_k_asyncio_tasks[] = "asyncio.tasks";
@@ -1724,6 +1724,7 @@ static const char __pyx_k_Declarative_inversion_of_control_2[] = "Declarative in
 static PyObject *__pyx_kp_s_0_can_contain_only_1_instances;
 static PyObject *__pyx_kp_s_Abstract_container;
 static PyObject *__pyx_n_s_AttributeError;
+static PyObject *__pyx_n_s_BaseSingleton;
 static PyObject *__pyx_n_s_Container;
 static PyObject *__pyx_kp_s_Container_0_could_not_be_overrid;
 static PyObject *__pyx_kp_s_Container_0_could_not_be_overrid_2;
@@ -1771,7 +1772,6 @@ static PyObject *__pyx_n_s_NotImplementedError;
 static PyObject *__pyx_n_s_Object;
 static PyObject *__pyx_n_s_Provider;
 static PyObject *__pyx_n_s_Resource;
-static PyObject *__pyx_n_s_Singleton;
 static PyObject *__pyx_kp_s_Wiring_requires_Python_3_6_or_ab;
 static PyObject *__pyx_n_s__11;
 static PyObject *__pyx_n_s_add_metaclass;
@@ -6370,13 +6370,13 @@ static PyObject *__pyx_pf_19dependency_injector_10containers_16DynamicContainer_
  *             provider.apply_overridings()
  * 
  *     def reset_singletons(self):             # <<<<<<<<<<<<<<
- *         """Reset all container singletons."""
- *         for provider in self.traverse(types=[providers.Singleton]):
+ *         """Reset container singletons."""
+ *         for provider in self.traverse(types=[providers.BaseSingleton]):
  */
 
 /* Python wrapper */
 static PyObject *__pyx_pw_19dependency_injector_10containers_16DynamicContainer_34reset_singletons(PyObject *__pyx_self, PyObject *__pyx_v_self); /*proto*/
-static char __pyx_doc_19dependency_injector_10containers_16DynamicContainer_33reset_singletons[] = "Reset all container singletons.";
+static char __pyx_doc_19dependency_injector_10containers_16DynamicContainer_33reset_singletons[] = "Reset container singletons.";
 static PyMethodDef __pyx_mdef_19dependency_injector_10containers_16DynamicContainer_34reset_singletons = {"reset_singletons", (PyCFunction)__pyx_pw_19dependency_injector_10containers_16DynamicContainer_34reset_singletons, METH_O, __pyx_doc_19dependency_injector_10containers_16DynamicContainer_33reset_singletons};
 static PyObject *__pyx_pw_19dependency_injector_10containers_16DynamicContainer_34reset_singletons(PyObject *__pyx_self, PyObject *__pyx_v_self) {
   PyObject *__pyx_r = 0;
@@ -6406,8 +6406,8 @@ static PyObject *__pyx_pf_19dependency_injector_10containers_16DynamicContainer_
 
   /* "dependency_injector/containers.pyx":276
  *     def reset_singletons(self):
- *         """Reset all container singletons."""
- *         for provider in self.traverse(types=[providers.Singleton]):             # <<<<<<<<<<<<<<
+ *         """Reset container singletons."""
+ *         for provider in self.traverse(types=[providers.BaseSingleton]):             # <<<<<<<<<<<<<<
  *             provider.reset()
  * 
  */
@@ -6417,7 +6417,7 @@ static PyObject *__pyx_pf_19dependency_injector_10containers_16DynamicContainer_
   __Pyx_GOTREF(__pyx_t_2);
   __Pyx_GetModuleGlobalName(__pyx_t_3, __pyx_n_s_providers); if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 276, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_t_3);
-  __pyx_t_4 = __Pyx_PyObject_GetAttrStr(__pyx_t_3, __pyx_n_s_Singleton); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 276, __pyx_L1_error)
+  __pyx_t_4 = __Pyx_PyObject_GetAttrStr(__pyx_t_3, __pyx_n_s_BaseSingleton); if (unlikely(!__pyx_t_4)) __PYX_ERR(0, 276, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_t_4);
   __Pyx_DECREF(__pyx_t_3); __pyx_t_3 = 0;
   __pyx_t_3 = PyList_New(1); if (unlikely(!__pyx_t_3)) __PYX_ERR(0, 276, __pyx_L1_error)
@@ -6475,8 +6475,8 @@ static PyObject *__pyx_pf_19dependency_injector_10containers_16DynamicContainer_
     __pyx_t_3 = 0;
 
     /* "dependency_injector/containers.pyx":277
- *         """Reset all container singletons."""
- *         for provider in self.traverse(types=[providers.Singleton]):
+ *         """Reset container singletons."""
+ *         for provider in self.traverse(types=[providers.BaseSingleton]):
  *             provider.reset()             # <<<<<<<<<<<<<<
  * 
  * 
@@ -6502,8 +6502,8 @@ static PyObject *__pyx_pf_19dependency_injector_10containers_16DynamicContainer_
 
     /* "dependency_injector/containers.pyx":276
  *     def reset_singletons(self):
- *         """Reset all container singletons."""
- *         for provider in self.traverse(types=[providers.Singleton]):             # <<<<<<<<<<<<<<
+ *         """Reset container singletons."""
+ *         for provider in self.traverse(types=[providers.BaseSingleton]):             # <<<<<<<<<<<<<<
  *             provider.reset()
  * 
  */
@@ -6514,8 +6514,8 @@ static PyObject *__pyx_pf_19dependency_injector_10containers_16DynamicContainer_
  *             provider.apply_overridings()
  * 
  *     def reset_singletons(self):             # <<<<<<<<<<<<<<
- *         """Reset all container singletons."""
- *         for provider in self.traverse(types=[providers.Singleton]):
+ *         """Reset container singletons."""
+ *         for provider in self.traverse(types=[providers.BaseSingleton]):
  */
 
   /* function exit code */
@@ -12153,6 +12153,7 @@ static __Pyx_StringTabEntry __pyx_string_tab[] = {
   {&__pyx_kp_s_0_can_contain_only_1_instances, __pyx_k_0_can_contain_only_1_instances, sizeof(__pyx_k_0_can_contain_only_1_instances), 0, 0, 1, 0},
   {&__pyx_kp_s_Abstract_container, __pyx_k_Abstract_container, sizeof(__pyx_k_Abstract_container), 0, 0, 1, 0},
   {&__pyx_n_s_AttributeError, __pyx_k_AttributeError, sizeof(__pyx_k_AttributeError), 0, 0, 1, 1},
+  {&__pyx_n_s_BaseSingleton, __pyx_k_BaseSingleton, sizeof(__pyx_k_BaseSingleton), 0, 0, 1, 1},
   {&__pyx_n_s_Container, __pyx_k_Container, sizeof(__pyx_k_Container), 0, 0, 1, 1},
   {&__pyx_kp_s_Container_0_could_not_be_overrid, __pyx_k_Container_0_could_not_be_overrid, sizeof(__pyx_k_Container_0_could_not_be_overrid), 0, 0, 1, 0},
   {&__pyx_kp_s_Container_0_could_not_be_overrid_2, __pyx_k_Container_0_could_not_be_overrid_2, sizeof(__pyx_k_Container_0_could_not_be_overrid_2), 0, 0, 1, 0},
@@ -12200,7 +12201,6 @@ static __Pyx_StringTabEntry __pyx_string_tab[] = {
   {&__pyx_n_s_Object, __pyx_k_Object, sizeof(__pyx_k_Object), 0, 0, 1, 1},
   {&__pyx_n_s_Provider, __pyx_k_Provider, sizeof(__pyx_k_Provider), 0, 0, 1, 1},
   {&__pyx_n_s_Resource, __pyx_k_Resource, sizeof(__pyx_k_Resource), 0, 0, 1, 1},
-  {&__pyx_n_s_Singleton, __pyx_k_Singleton, sizeof(__pyx_k_Singleton), 0, 0, 1, 1},
   {&__pyx_kp_s_Wiring_requires_Python_3_6_or_ab, __pyx_k_Wiring_requires_Python_3_6_or_ab, sizeof(__pyx_k_Wiring_requires_Python_3_6_or_ab), 0, 0, 1, 0},
   {&__pyx_n_s__11, __pyx_k__11, sizeof(__pyx_k__11), 0, 0, 1, 1},
   {&__pyx_n_s_add_metaclass, __pyx_k_add_metaclass, sizeof(__pyx_k_add_metaclass), 0, 0, 1, 1},
@@ -12648,8 +12648,8 @@ static CYTHON_SMALL_CODE int __Pyx_InitCachedConstants(void) {
  *             provider.apply_overridings()
  * 
  *     def reset_singletons(self):             # <<<<<<<<<<<<<<
- *         """Reset all container singletons."""
- *         for provider in self.traverse(types=[providers.Singleton]):
+ *         """Reset container singletons."""
+ *         for provider in self.traverse(types=[providers.BaseSingleton]):
  */
   __pyx_tuple__52 = PyTuple_Pack(2, __pyx_n_s_self_2, __pyx_n_s_provider); if (unlikely(!__pyx_tuple__52)) __PYX_ERR(0, 274, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_tuple__52);
@@ -13645,8 +13645,8 @@ if (!__Pyx_RefNanny) {
  *             provider.apply_overridings()
  * 
  *     def reset_singletons(self):             # <<<<<<<<<<<<<<
- *         """Reset all container singletons."""
- *         for provider in self.traverse(types=[providers.Singleton]):
+ *         """Reset container singletons."""
+ *         for provider in self.traverse(types=[providers.BaseSingleton]):
  */
   __pyx_t_10 = __Pyx_CyFunction_New(&__pyx_mdef_19dependency_injector_10containers_16DynamicContainer_34reset_singletons, 0, __pyx_n_s_DynamicContainer_reset_singleton, NULL, __pyx_n_s_dependency_injector_containers, __pyx_d, ((PyObject *)__pyx_codeobj__53)); if (unlikely(!__pyx_t_10)) __PYX_ERR(0, 274, __pyx_L1_error)
   __Pyx_GOTREF(__pyx_t_10);

src/dependency_injector/containers.pyi

@@ -21,6 +21,7 @@ from .providers import Provider
 C_Base = TypeVar('C_Base', bound='Container')
 C = TypeVar('C', bound='DeclarativeContainer')
 C_Overriding = TypeVar('C_Overriding', bound='DeclarativeContainer')
+TT = TypeVar('TT')
 
 
 class Container:
@@ -46,10 +47,10 @@ class Container:
     def apply_container_providers_overridings(self) -> None: ...
     def reset_singletons(self) -> None: ...
     @overload
-    def traverse(self, types: Optional[Sequence[Type]] = None) -> Iterator[Provider]: ...
+    def traverse(self, types: Optional[Sequence[TT]] = None) -> Iterator[TT]: ...
     @classmethod
     @overload
-    def traverse(cls, types: Optional[Sequence[Type]] = None) -> Iterator[Provider]: ...
+    def traverse(cls, types: Optional[Sequence[TT]] = None) -> Iterator[TT]: ...
 
 
 class DynamicContainer(Container): ...

src/dependency_injector/containers.pyx

@@ -272,8 +272,8 @@ class DynamicContainer(Container):
             provider.apply_overridings()
 
     def reset_singletons(self):
-        """Reset all container singletons."""
-        for provider in self.traverse(types=[providers.Singleton]):
+        """Reset container singletons."""
+        for provider in self.traverse(types=[providers.BaseSingleton]):
             provider.reset()
 
 

src/dependency_injector/providers.pyi

@@ -36,6 +36,7 @@ from . import resources
 
 Injection = Any
 T = TypeVar('T')
+TT = TypeVar('TT')
 
 
 class OverridingContext:
@@ -76,7 +77,7 @@ class Provider(Generic[T]):
     def is_async_mode_undefined(self) -> bool: ...
     @property
     def related(self) -> _Iterator[Provider]: ...
-    def traverse(self, types: Optional[_Iterable[Type]] = None) -> _Iterator[Provider]: ...
+    def traverse(self, types: Optional[_Iterable[TT]] = None) -> _Iterator[TT]: ...
     def _copy_overridings(self, copied: Provider, memo: Optional[_Dict[Any, Any]]) -> None: ...
 
 
@@ -266,6 +267,7 @@ class BaseSingleton(Provider[T]):
     def set_attributes(self, **kwargs: Injection) -> BaseSingleton[T]: ...
     def clear_attributes(self) -> BaseSingleton[T]: ...
     def reset(self) -> None: ...
+    def full_reset(self) -> None: ...
 
 
 class Singleton(BaseSingleton[T]): ...

src/dependency_injector/providers.pyx

@@ -2468,6 +2468,15 @@ cdef class BaseSingleton(Provider):
         """
         raise NotImplementedError()
 
+    def full_reset(self):
+        """Reset cached instance in current and all underlying singletons, if any.
+
+        :rtype: None
+        """
+        self.reset()
+        for provider in self.traverse(types=[BaseSingleton]):
+            provider.reset()
+
     @property
     def related(self):
         """Return related providers generator."""

tests/unit/providers/test_singletons_py2_py3.py

@@ -355,6 +355,37 @@ class _BaseSingletonTestCase(object):
 
         self.assertIsNot(instance1, instance2)
 
+    def test_reset_with_singleton(self):
+        dependent_singleton = providers.Singleton(object)
+        provider = self.singleton_cls(dict, dependency=dependent_singleton)
+
+        dependent_instance = dependent_singleton()
+        instance1 = provider()
+        self.assertIs(instance1['dependency'], dependent_instance)
+
+        provider.reset()
+
+        instance2 = provider()
+        self.assertIs(instance1['dependency'], dependent_instance)
+
+        self.assertIsNot(instance1, instance2)
+
+    def test_full_reset(self):
+        dependent_singleton = providers.Singleton(object)
+        provider = self.singleton_cls(dict, dependency=dependent_singleton)
+
+        dependent_instance1 = dependent_singleton()
+        instance1 = provider()
+        self.assertIs(instance1['dependency'], dependent_instance1)
+
+        provider.full_reset()
+
+        dependent_instance2 = dependent_singleton()
+        instance2 = provider()
+        self.assertIsNot(instance2['dependency'], dependent_instance1)
+        self.assertIsNot(dependent_instance1, dependent_instance2)
+        self.assertIsNot(instance1, instance2)
+
 
 class SingletonTests(_BaseSingletonTestCase, unittest.TestCase):