Resources (#312)

* Add prototype

* Add example

* Remove typing erros in Python 2.7 and 3.4

* Move resources example

* Draft resources docs

* Update resources docs

* Fix repr

* Rename dict provider test

* Add more tests

* Add tests + refactoring

* Add more tests

* Update tests to run only on 3.5+

* Update setup.py

* Add typing tests

* Update changelog

* Fix generator iteration

* Remove contextlib

* Hotfix aiohttp issue

* Move aiohttp fix to tox.ini

* Move aiohttp fix to a different place in tox

README.rst

@@ -57,17 +57,20 @@ It helps implementing the dependency injection principle.
 Key features of the ``Dependency Injector``:
 
 - **Providers**. Provides ``Factory``, ``Singleton``, ``Callable``, ``Coroutine``, ``Object``,
-  ``List``, ``Dict``, ``Configuration``, ``Dependency`` and ``Selector`` providers that help
-  assembling your objects.
+  ``List``, ``Dict``, ``Configuration``, ``Resource``, ``Dependency`` and ``Selector`` providers
+  that help assembling your objects.
   See `Providers <https://python-dependency-injector.ets-labs.org/providers/index.html>`_.
 - **Overriding**. Can override any provider by another provider on the fly. This helps in testing
   and configuring dev / stage environment to replace API clients with stubs etc. See
   `Provider overriding <https://python-dependency-injector.ets-labs.org/providers/overriding.html>`_.
-- **Configuration**. Read configuration from ``yaml`` & ``ini`` files, environment variables
+- **Configuration**. Reads configuration from ``yaml`` & ``ini`` files, environment variables
   and dictionaries.
   See `Configuration provider <https://python-dependency-injector.ets-labs.org/providers/configuration.html>`_.
 - **Containers**. Provides declarative and dynamic containers.
   See `Containers <https://python-dependency-injector.ets-labs.org/containers/index.html>`_.
+- **Resources**. Helps with initialization and configuring of logging, event loop, thread
+  or process pool, etc.
+  See `Resource provider <https://python-dependency-injector.ets-labs.org/providers/resource.html>`_.
 - **Wiring**. Injects dependencies into functions and methods. Helps integrating with
   other frameworks: Django, Flask, Aiohttp, etc.
   See `Wiring <https://python-dependency-injector.ets-labs.org/wiring.html>`_.

docs/index.rst

@@ -69,13 +69,15 @@ It helps implementing the dependency injection principle.
 Key features of the ``Dependency Injector``:
 
 - **Providers**. Provides ``Factory``, ``Singleton``, ``Callable``, ``Coroutine``, ``Object``,
-  ``List``, ``Dict``, ``Configuration``, ``Dependency`` and ``Selector`` providers that help
-  assembling your objects. See :ref:`providers`.
+  ``List``, ``Dict``, ``Configuration``, ``Resource``, ``Dependency`` and ``Selector`` providers
+  that help assembling your objects. See :ref:`providers`.
 - **Overriding**. Can override any provider by another provider on the fly. This helps in testing
   and configuring dev / stage environment to replace API clients with stubs etc. See
   :ref:`provider-overriding`.
-- **Configuration**. Read configuration from ``yaml`` & ``ini`` files, environment variables
+- **Configuration**. Reads configuration from ``yaml`` & ``ini`` files, environment variables
   and dictionaries. See :ref:`configuration-provider`.
+- **Resources**. Helps with initialization and configuring of logging, event loop, thread
+  or process pool, etc. See :ref:`resource-provider`.
 - **Containers**. Provides declarative and dynamic containers. See :ref:`containers`.
 - **Wiring**. Injects dependencies into functions and methods. Helps integrating with
   other frameworks: Django, Flask, Aiohttp, etc. See :ref:`wiring`.

docs/introduction/key_features.rst

@@ -11,13 +11,15 @@ Key features
 Key features of the ``Dependency Injector``:
 
 - **Providers**. Provides ``Factory``, ``Singleton``, ``Callable``, ``Coroutine``, ``Object``,
-  ``List``, ``Dict``, ``Configuration``, ``Dependency`` and ``Selector`` providers that help
-  assembling your objects. See :ref:`providers`.
+  ``List``, ``Dict``, ``Configuration``, ``Resource``, ``Dependency`` and ``Selector`` providers
+  that help assembling your objects. See :ref:`providers`.
 - **Overriding**. Can override any provider by another provider on the fly. This helps in testing
   and configuring dev / stage environment to replace API clients with stubs etc. See
   :ref:`provider-overriding`.
-- **Configuration**. Read configuration from ``yaml`` & ``ini`` files, environment variables
+- **Configuration**. Reads configuration from ``yaml`` & ``ini`` files, environment variables
   and dictionaries. See :ref:`configuration-provider`.
+- **Resources**. Helps with initialization and configuring of logging, event loop, thread
+  or process pool, etc. See :ref:`resource-provider`.
 - **Containers**. Provides declarative and dynamic containers. See :ref:`containers`.
 - **Wiring**. Injects dependencies into functions and methods. Helps integrating with
   other frameworks: Django, Flask, Aiohttp, etc. See :ref:`wiring`.

docs/main/changelog.rst

@@ -9,6 +9,7 @@ follows `Semantic versioning`_
 
 Develop
 -------
+- Add ``Resource`` provider.
 - Add ``Dict`` provider.
 - "Un-deprecate" ``@containers.override()`` and ``@containers.copy()`` decorators (
   see `Issue 301 <https://github.com/ets-labs/python-dependency-injector/issues/301>`_
@@ -16,6 +17,7 @@ Develop
 - Add favicon.
 - Remove redirects that occur while getting badge images to optimize docs load speed.
 - Update license year.
+- Update short description on PyPI.
 
 4.0.6
 -----

docs/providers/index.rst

@@ -45,6 +45,7 @@ Providers module API docs - :py:mod:`dependency_injector.providers`
     list
     dict
     configuration
+    resource
     selector
     dependency
     overriding

docs/providers/resource.rst

@@ -0,0 +1,206 @@
+.. _resource-provider:
+
+Resource provider
+=================
+
+.. meta::
+   :keywords: Python,DI,Dependency injection,IoC,Inversion of Control,Resource,Injection,
+              Logging,Event Loop,Thread Pool
+   :description: Resource provider provides a component with initialization and shutdown. It works
+                 well for configuring logging, event loop, thread or process pool, etc.
+                 This page demonstrates how to use resource provider.
+
+.. currentmodule:: dependency_injector.providers
+
+:py:class:`Resource` provider provides a component with initialization and shutdown.
+
+.. literalinclude:: ../../examples/providers/resource.py
+   :language: python
+   :lines: 3-
+
+Resource providers help to initialize and configure logging, event loop, thread or process pool, etc.
+
+Resource provider is similar to ``Singleton``. Resource initialization happens only once.
+You can do injections and use provided instance the same way like you do with any other provider.
+
+.. code-block:: python
+   :emphasize-lines: 12
+
+   class Container(containers.DeclarativeContainer):
+
+       config = providers.Configuration()
+
+       thread_pool = providers.Resource(
+           init_threat_pool,
+           max_workers=config.max_workers,
+       )
+
+       dispatcher = providers.Factory(
+           TaskDispatcher,
+           executor=thread_pool,
+       )
+
+Container has an interface to initialize and shutdown all resources:
+
+.. code-block:: python
+
+   container = Container()
+   container.init_resources()
+   container.shutdown_resources()
+
+You also can initialize and shutdown resources one-by-one using ``init()`` and
+``shutdown()`` methods of the provider:
+
+.. code-block:: python
+
+   container = Container()
+   container.thread_pool.init()
+   container.thread_pool.shutdown()
+
+Resource provider supports 3 types of initializers:
+
+- Function
+- Generator
+- Subclass of ``resources.Resource``
+
+Function initializer
+--------------------
+
+Function is the most common way to specify resource initialization:
+
+.. code-block:: python
+
+   def init_resource(argument1=..., argument2=...):
+       return SomeResource()
+
+
+   class Container(containers.DeclarativeContainer):
+
+       resource = providers.Resource(
+           init_resource,
+           argument1=...,
+           argument2=...,
+       )
+
+Function initializer may not return a value. This often happens when
+you configure global resource:
+
+.. code-block:: python
+
+   import logging.config
+
+
+   class Container(containers.DeclarativeContainer):
+
+       configure_logging = providers.Resource(
+           logging.config.fileConfig,
+           fname='logging.ini',
+       )
+
+Function initializer does not support shutdown.
+
+Generator initializer
+---------------------
+
+Resource provider can use 2-step generators:
+
+- First step of generator is an initialization phase
+- The second is step is a shutdown phase
+
+.. code-block:: python
+
+   def init_resource(argument1=..., argument2=...):
+       resource = SomeResource()  # initialization
+
+       yield resource
+
+       # shutdown
+       ...
+
+
+   class Container(containers.DeclarativeContainer):
+
+       resource = providers.Resource(
+           init_resource,
+           argument1=...,
+           argument2=...,
+       )
+
+Generator initialization phase ends on the first ``yield`` statement. You can return a
+resource object using ``yield resource`` like in the example above. Returning of the
+object is not mandatory. You can leave ``yield`` statement empty:
+
+.. code-block:: python
+
+   def init_resource(argument1=..., argument2=...):
+       # initialization
+       ...
+
+       yield
+
+       # shutdown
+       ...
+
+
+   class Container(containers.DeclarativeContainer):
+
+       resource = providers.Resource(
+           init_resource,
+           argument1=...,
+           argument2=...,
+       )
+
+Subclass initializer
+--------------------
+
+You can create resource initializer by implementing a subclass of the ``resources.Resource``:
+
+.. code-block:: python
+
+   from dependency_injector import resources
+
+
+   class MyResource(resources.Resource):
+
+       def init(self, argument1=..., argument2=...) -> SomeResource:
+           return SomeResource()
+
+       def shutdown(self, resource: SomeResource) -> None:
+           # shutdown
+           ...
+
+
+   class Container(containers.DeclarativeContainer):
+
+       resource = providers.Resource(
+           MyResource,
+           argument1=...,
+           argument2=...,
+       )
+
+Subclass must implement two methods: ``init()`` and ``shutdown()``.
+
+Method ``init()`` receives arguments specified in resource provider.
+It performs initialization and returns resource object. Returning of the object
+is not mandatory.
+
+Method ``shutdown()`` receives resource object returned from ``init()``. If ``init()``
+didn't return an object ``shutdown()`` method will be called anyway with ``None`` as a
+first argument.
+
+.. code-block:: python
+
+   from dependency_injector import resources
+
+
+   class MyResource(resources.Resource):
+
+       def init(self, argument1=..., argument2=...) -> None:
+           # initialization
+           ...
+
+       def shutdown(self, _: None) -> None:
+           # shutdown
+           ...
+
+.. disqus::

examples/providers/resource.py

@@ -0,0 +1,41 @@
+"""`Resource` provider example."""
+
+import sys
+import logging
+from concurrent.futures import ThreadPoolExecutor
+
+from dependency_injector import containers, providers
+
+
+def init_threat_pool(max_workers: int):
+    thread_pool = ThreadPoolExecutor(max_workers=max_workers)
+    yield thread_pool
+    thread_pool.shutdown(wait=True)
+
+
+class Container(containers.DeclarativeContainer):
+
+    config = providers.Configuration()
+
+    thread_pool = providers.Resource(
+        init_threat_pool,
+        max_workers=config.max_workers,
+    )
+
+    logging = providers.Resource(
+        logging.basicConfig,
+        level=logging.INFO,
+        stream=sys.stdout,
+    )
+
+
+if __name__ == '__main__':
+    container = Container(config={'max_workers': 4})
+
+    container.init_resources()
+
+    logging.info('Resources are initialized')
+    thread_pool = container.thread_pool()
+    thread_pool.map(print, range(10))
+
+    container.shutdown_resources()

setup.py

@@ -31,11 +31,11 @@ if os.environ.get('DEPENDENCY_INJECTOR_DEBUG_MODE') == '1':
 
 setup(name='dependency-injector',
       version=version,
-      description='Dependency injection microframework for Python',
+      description='Dependency injection framework for Python',
       long_description=description,
       author='ETS Labs',
       author_email='rmogilatov@gmail.com',
-      maintainer='Roman Mogilatov',
+      maintainer='Roman Mogylatov',
       maintainer_email='rmogilatov@gmail.com',
       url='https://github.com/ets-labs/python-dependency-injector',
       download_url='https://pypi.python.org/pypi/dependency_injector',

src/dependency_injector/containers.pyi

@@ -25,6 +25,8 @@ class Container:
     def resolve_provider_name(self, provider_to_resolve: Provider) -> Optional[str]: ...
     def wire(self, modules: Optional[Iterable[ModuleType]] = None, packages: Optional[Iterable[ModuleType]] = None) -> None: ...
     def unwire(self) -> None: ...
+    def init_resources(self) -> None: ...
+    def shutdown_resources(self) -> None: ...
 
 
 class DynamicContainer(Container): ...

src/dependency_injector/containers.pyx

@@ -7,6 +7,7 @@ import six
 from .errors import Error
 from .providers cimport (
     Provider,
+    Resource,
     deepcopy,
 )
 
@@ -213,6 +214,19 @@ class DynamicContainer(object):
         self.wired_to_modules.clear()
         self.wired_to_packages.clear()
 
+    def init_resources(self):
+        """Initialize all container resources."""
+        for provider in self.providers.values():
+            if not isinstance(provider, Resource):
+                continue
+            provider.init()
+
+    def shutdown_resources(self):
+        """Shutdown all container resources."""
+        for provider in self.providers.values():
+            if not isinstance(provider, Resource):
+                continue
+            provider.shutdown()
 
 
 class DeclarativeContainerMetaClass(type):

src/dependency_injector/providers.pxd

@@ -191,6 +191,21 @@ cdef class Dict(Provider):
     cpdef object _provide(self, tuple args, dict kwargs)
 
 
+cdef class Resource(Provider):
+    cdef object __initializer
+    cdef bint __initialized
+    cdef object __shutdowner
+    cdef object __resource
+
+    cdef tuple __args
+    cdef int __args_len
+
+    cdef tuple __kwargs
+    cdef int __kwargs_len
+
+    cpdef object _provide(self, tuple args, dict kwargs)
+
+
 cdef class Container(Provider):
     cdef object __container_cls
     cdef dict __overriding_providers

src/dependency_injector/providers.pyi

@@ -13,8 +13,13 @@ from typing import (
     Optional,
     Union,
     Coroutine as _Coroutine,
+    Iterator as _Iterator,
+    Generator as _Generator,
+    overload,
 )
 
+from . import resources
+
 
 Injection = Any
 T = TypeVar('T')
@@ -274,6 +279,30 @@ class Dict(Provider):
     def clear_kwargs(self) -> Dict: ...
 
 
+class Resource(Provider, Generic[T]):
+    @overload
+    def __init__(self, initializer: _Callable[..., resources.Resource[T]], *args: Injection, **kwargs: Injection) -> None: ...
+    @overload
+    def __init__(self, initializer: _Callable[..., _Iterator[T]], *args: Injection, **kwargs: Injection) -> None: ...
+    @overload
+    def __init__(self, initializer: _Callable[..., T], *args: Injection, **kwargs: Injection) -> None: ...
+    def __call__(self, *args: Injection, **kwargs: Injection) -> T: ...
+    @property
+    def args(self) -> Tuple[Injection]: ...
+    def add_args(self, *args: Injection) -> Resource: ...
+    def set_args(self, *args: Injection) -> Resource: ...
+    def clear_args(self) -> Resource: ...
+    @property
+    def kwargs(self) -> _Dict[Any, Injection]: ...
+    def add_kwargs(self, **kwargs: Injection) -> Resource: ...
+    def set_kwargs(self, **kwargs: Injection) -> Resource: ...
+    def clear_kwargs(self) -> Resource: ...
+    @property
+    def initialized(self) -> bool: ...
+    def init(self) -> T: ...
+    def shutdown(self) -> None: ...
+
+
 class Container(Provider):
 
     def __init__(self, container_cls: Type[T], container: Optional[T] = None, **overriding_providers: Provider) -> None: ...

src/dependency_injector/providers.pyx

@@ -3,6 +3,7 @@
 from __future__ import absolute_import
 
 import copy
+import inspect
 import os
 import re
 import sys
@@ -2502,7 +2503,7 @@ cdef class Dict(Provider):
 
         :rtype: str
         """
-        return represent_provider(provider=self, provides=dict(self.kwargs))
+        return represent_provider(provider=self, provides=self.kwargs)
 
     @property
     def kwargs(self):
@@ -2551,6 +2552,211 @@ cdef class Dict(Provider):
         return __provide_keyword_args(kwargs, self.__kwargs, self.__kwargs_len)
 
 
+cdef class Resource(Provider):
+    """Resource provider provides a component with initialization and shutdown."""
+
+    def __init__(self, initializer, *args, **kwargs):
+        self.__initializer = initializer
+        self.__initialized = False
+        self.__resource = None
+        self.__shutdowner = None
+
+        self.__args = tuple()
+        self.__args_len = 0
+        self.set_args(*args)
+
+        self.__kwargs = tuple()
+        self.__kwargs_len = 0
+        self.set_kwargs(**kwargs)
+
+        super().__init__()
+
+    def __deepcopy__(self, memo):
+        """Create and return full copy of provider."""
+        copied = memo.get(id(self))
+        if copied is not None:
+            return copied
+
+        if self.__initialized:
+            raise Error('Can not copy initialized resource')
+
+        copied = self.__class__(
+            self.__initializer,
+            *deepcopy(self.args, memo),
+            **deepcopy(self.kwargs, memo),
+        )
+        self._copy_overridings(copied, memo)
+
+        return copied
+
+    def __repr__(self):
+        return (
+            f'{self.__class__.__name__}({self.__initializer}, '
+            f'initialized={self.__initialized})'
+        )
+
+    @property
+    def args(self):
+        """Return positional argument injections."""
+        cdef int index
+        cdef PositionalInjection arg
+        cdef list args
+
+        args = list()
+        for index in range(self.__args_len):
+            arg = self.__args[index]
+            args.append(arg.__value)
+        return tuple(args)
+
+    def add_args(self, *args):
+        """Add positional argument injections.
+
+        :return: Reference ``self``
+        """
+        self.__args += parse_positional_injections(args)
+        self.__args_len = len(self.__args)
+        return self
+
+    def set_args(self, *args):
+        """Set positional argument injections.
+
+        Existing positional argument injections are dropped.
+
+        :return: Reference ``self``
+        """
+        self.__args = parse_positional_injections(args)
+        self.__args_len = len(self.__args)
+        return self
+
+    def clear_args(self):
+        """Drop positional argument injections.
+
+        :return: Reference ``self``
+        """
+        self.__args = tuple()
+        self.__args_len = len(self.__args)
+        return self
+
+    @property
+    def kwargs(self):
+        """Return keyword argument injections."""
+        cdef int index
+        cdef NamedInjection kwarg
+        cdef dict kwargs
+
+        kwargs = dict()
+        for index in range(self.__kwargs_len):
+            kwarg = self.__kwargs[index]
+            kwargs[kwarg.__name] = kwarg.__value
+        return kwargs
+
+    def add_kwargs(self, **kwargs):
+        """Add keyword argument injections.
+
+        :return: Reference ``self``
+        """
+        self.__kwargs += parse_named_injections(kwargs)
+        self.__kwargs_len = len(self.__kwargs)
+        return self
+
+    def set_kwargs(self, **kwargs):
+        """Set keyword argument injections.
+
+        Existing keyword argument injections are dropped.
+
+        :return: Reference ``self``
+        """
+        self.__kwargs = parse_named_injections(kwargs)
+        self.__kwargs_len = len(self.__kwargs)
+        return self
+
+    def clear_kwargs(self):
+        """Drop keyword argument injections.
+
+        :return: Reference ``self``
+        """
+        self.__kwargs = tuple()
+        self.__kwargs_len = len(self.__kwargs)
+        return self
+
+    @property
+    def initialized(self):
+        """Check if resource is initialized."""
+        return self.__initialized
+
+    def init(self):
+        """Initialize resource."""
+        return self.__call__()
+
+    def shutdown(self):
+        """Shutdown resource."""
+        if not self.__initialized:
+            return
+
+        if self.__shutdowner:
+            try:
+                self.__shutdowner(self.__resource)
+            except StopIteration:
+                pass
+
+        self.__resource = None
+        self.__initialized = False
+        self.__shutdowner = None
+
+    cpdef object _provide(self, tuple args, dict kwargs):
+        if self.__initialized:
+            return self.__resource
+
+        if self._is_resource_subclass(self.__initializer):
+            initializer = self.__initializer()
+            self.__resource = __call(
+                initializer.init,
+                args,
+                self.__args,
+                self.__args_len,
+                kwargs,
+                self.__kwargs,
+                self.__kwargs_len,
+            )
+            self.__shutdowner = initializer.shutdown
+        elif inspect.isgeneratorfunction(self.__initializer):
+            initializer = __call(
+                self.__initializer,
+                args,
+                self.__args,
+                self.__args_len,
+                kwargs,
+                self.__kwargs,
+                self.__kwargs_len,
+            )
+            self.__resource = next(initializer)
+            self.__shutdowner = initializer.send
+        elif callable(self.__initializer):
+            self.__resource = __call(
+                self.__initializer,
+                args,
+                self.__args,
+                self.__args_len,
+                kwargs,
+                self.__kwargs,
+                self.__kwargs_len,
+            )
+        else:
+            raise Error('Unknown type of resource initializer')
+
+        self.__initialized = True
+        return self.__resource
+
+    @staticmethod
+    def _is_resource_subclass(instance):
+        if  sys.version_info < (3, 5):
+            return False
+        if not isinstance(instance, CLASS_TYPES):
+            return
+        from . import resources
+        return issubclass(instance, resources.Resource)
+
+
 cdef class Container(Provider):
     """Container provider provides an instance of declarative container.
 

src/dependency_injector/resources.py

@@ -0,0 +1,31 @@
+"""Resources module."""
+
+import abc
+import sys
+from typing import TypeVar, Generic
+
+if sys.version_info < (3, 7):
+    from typing import GenericMeta
+else:
+    class GenericMeta(type):
+        ...
+
+
+T = TypeVar('T')
+
+
+class ResourceMeta(GenericMeta, abc.ABCMeta):
+    def __getitem__(cls, item):
+        # Spike for Python 3.6
+        return cls(item)
+
+
+class Resource(Generic[T], metaclass=ResourceMeta):
+
+    @abc.abstractmethod
+    def init(self, *args, **kwargs) -> T:
+        ...
+
+    @abc.abstractmethod
+    def shutdown(self, resource: T) -> None:
+        ...

tests/typing/resource.py

@@ -0,0 +1,43 @@
+from typing import List, Iterator, Generator
+
+from dependency_injector import providers, resources
+
+
+# Test 1: to check the return type with function
+def init1() -> List[int]:
+    return []
+
+
+provider1 = providers.Resource(init1)
+var1: List[int] = provider1()
+
+
+# Test 2: to check the return type with iterator
+def init2() -> Iterator[List[int]]:
+    yield []
+
+
+provider2 = providers.Resource(init2)
+var2: List[int] = provider2()
+
+
+# Test 3: to check the return type with generator
+def init3() -> Generator[List[int], None, None]:
+    yield []
+
+
+provider3 = providers.Resource(init3)
+var3: List[int] = provider3()
+
+
+# Test 4: to check the return type with resource subclass
+class MyResource4(resources.Resource[List[int]]):
+    def init(self, *args, **kwargs) -> List[int]:
+        return []
+
+    def shutdown(self, resource: List[int]) -> None:
+        ...
+
+
+provider4 = providers.Resource(MyResource4)
+var4: List[int] = provider4()

tests/unit/containers/test_dynamic_py2_py3.py

@@ -186,6 +186,52 @@ class DeclarativeContainerInstanceTests(unittest.TestCase):
         self.assertEqual(container.overridden, tuple())
         self.assertEqual(container.p11.overridden, tuple())
 
+    def test_init_shutdown_resources(self):
+        def _init1():
+            _init1.init_counter += 1
+            yield
+            _init1.shutdown_counter += 1
+
+        _init1.init_counter = 0
+        _init1.shutdown_counter = 0
+
+        def _init2():
+            _init2.init_counter += 1
+            yield
+            _init2.shutdown_counter += 1
+
+        _init2.init_counter = 0
+        _init2.shutdown_counter = 0
+
+        class Container(containers.DeclarativeContainer):
+            resource1 = providers.Resource(_init1)
+            resource2 = providers.Resource(_init2)
+
+        container = Container()
+        self.assertEqual(_init1.init_counter, 0)
+        self.assertEqual(_init1.shutdown_counter, 0)
+        self.assertEqual(_init2.init_counter, 0)
+        self.assertEqual(_init2.shutdown_counter, 0)
+
+        container.init_resources()
+        self.assertEqual(_init1.init_counter, 1)
+        self.assertEqual(_init1.shutdown_counter, 0)
+        self.assertEqual(_init2.init_counter, 1)
+        self.assertEqual(_init2.shutdown_counter, 0)
+
+        container.shutdown_resources()
+        self.assertEqual(_init1.init_counter, 1)
+        self.assertEqual(_init1.shutdown_counter, 1)
+        self.assertEqual(_init2.init_counter, 1)
+        self.assertEqual(_init2.shutdown_counter, 1)
+
+        container.init_resources()
+        container.shutdown_resources()
+        self.assertEqual(_init1.init_counter, 2)
+        self.assertEqual(_init1.shutdown_counter, 2)
+        self.assertEqual(_init2.init_counter, 2)
+        self.assertEqual(_init2.shutdown_counter, 2)
+
 
 if __name__ == '__main__':
     unittest.main()

tests/unit/providers/test_dict_py2_py3.py

@@ -93,7 +93,7 @@ class DictTests(unittest.TestCase):
 
         self.assertIs(provider_copy, provider_copy_memo)
 
-    def test_deepcopy_args(self):
+    def test_deepcopy_kwargs(self):
         provider = providers.Dict()
         dependent_provider1 = providers.Factory(list)
         dependent_provider2 = providers.Factory(dict)

tests/unit/providers/test_resource_py35.py

@@ -0,0 +1,322 @@
+"""Dependency injector resource provider unit tests."""
+
+import sys
+
+import unittest2 as unittest
+
+from dependency_injector import containers, providers, resources, errors
+
+
+def init_fn(*args, **kwargs):
+    return args, kwargs
+
+
+class ResourceTests(unittest.TestCase):
+
+    def test_is_provider(self):
+        self.assertTrue(providers.is_provider(providers.Resource(init_fn)))
+
+    def test_provided_instance_provider(self):
+        provider = providers.Resource(init_fn)
+        self.assertIsInstance(provider.provided, providers.ProvidedInstance)
+
+    def test_injection(self):
+        resource = object()
+
+        def _init():
+            _init.counter += 1
+            return resource
+        _init.counter = 0
+
+        class Container(containers.DeclarativeContainer):
+            resource = providers.Resource(_init)
+            dependency1 = providers.List(resource)
+            dependency2 = providers.List(resource)
+
+        container = Container()
+        list1 = container.dependency1()
+        list2 = container.dependency2()
+
+        self.assertEqual(list1, [resource])
+        self.assertIs(list1[0], resource)
+
+        self.assertEqual(list2, [resource])
+        self.assertIs(list2[0], resource)
+
+        self.assertEqual(_init.counter, 1)
+
+    def test_init_function(self):
+        def _init():
+            _init.counter += 1
+        _init.counter = 0
+
+        provider = providers.Resource(_init)
+
+        result1 = provider()
+        self.assertIsNone(result1)
+        self.assertEqual(_init.counter, 1)
+
+        result2 = provider()
+        self.assertIsNone(result2)
+        self.assertEqual(_init.counter, 1)
+
+        provider.shutdown()
+
+    def test_init_generator(self):
+        def _init():
+            _init.init_counter += 1
+            yield
+            _init.shutdown_counter += 1
+
+        _init.init_counter = 0
+        _init.shutdown_counter = 0
+
+        provider = providers.Resource(_init)
+
+        result1 = provider()
+        self.assertIsNone(result1)
+        self.assertEqual(_init.init_counter, 1)
+        self.assertEqual(_init.shutdown_counter, 0)
+
+        provider.shutdown()
+        self.assertEqual(_init.init_counter, 1)
+        self.assertEqual(_init.shutdown_counter, 1)
+
+        result2 = provider()
+        self.assertIsNone(result2)
+        self.assertEqual(_init.init_counter, 2)
+        self.assertEqual(_init.shutdown_counter, 1)
+
+        provider.shutdown()
+        self.assertEqual(_init.init_counter, 2)
+        self.assertEqual(_init.shutdown_counter, 2)
+
+    def test_init_class(self):
+        class TestResource(resources.Resource):
+            init_counter = 0
+            shutdown_counter = 0
+
+            def init(self):
+                self.__class__.init_counter += 1
+
+            def shutdown(self, _):
+                self.__class__.shutdown_counter += 1
+
+        provider = providers.Resource(TestResource)
+
+        result1 = provider()
+        self.assertIsNone(result1)
+        self.assertEqual(TestResource.init_counter, 1)
+        self.assertEqual(TestResource.shutdown_counter, 0)
+
+        provider.shutdown()
+        self.assertEqual(TestResource.init_counter, 1)
+        self.assertEqual(TestResource.shutdown_counter, 1)
+
+        result2 = provider()
+        self.assertIsNone(result2)
+        self.assertEqual(TestResource.init_counter, 2)
+        self.assertEqual(TestResource.shutdown_counter, 1)
+
+        provider.shutdown()
+        self.assertEqual(TestResource.init_counter, 2)
+        self.assertEqual(TestResource.shutdown_counter, 2)
+
+    def test_init_not_callable(self):
+        provider = providers.Resource(1)
+        with self.assertRaises(errors.Error):
+            provider.init()
+
+    def test_init_and_shutdown(self):
+        def _init():
+            _init.init_counter += 1
+            yield
+            _init.shutdown_counter += 1
+
+        _init.init_counter = 0
+        _init.shutdown_counter = 0
+
+        provider = providers.Resource(_init)
+
+        result1 = provider.init()
+        self.assertIsNone(result1)
+        self.assertEqual(_init.init_counter, 1)
+        self.assertEqual(_init.shutdown_counter, 0)
+
+        provider.shutdown()
+        self.assertEqual(_init.init_counter, 1)
+        self.assertEqual(_init.shutdown_counter, 1)
+
+        result2 = provider.init()
+        self.assertIsNone(result2)
+        self.assertEqual(_init.init_counter, 2)
+        self.assertEqual(_init.shutdown_counter, 1)
+
+        provider.shutdown()
+        self.assertEqual(_init.init_counter, 2)
+        self.assertEqual(_init.shutdown_counter, 2)
+
+    def test_initialized(self):
+        provider = providers.Resource(init_fn)
+        self.assertFalse(provider.initialized)
+
+        provider.init()
+        self.assertTrue(provider.initialized)
+
+        provider.shutdown()
+        self.assertFalse(provider.initialized)
+
+    def test_call_with_context_args(self):
+        provider = providers.Resource(init_fn, 'i1', 'i2')
+        self.assertEqual(provider('i3', i4=4), (('i1', 'i2', 'i3'), {'i4': 4}))
+
+    def test_fluent_interface(self):
+        provider = providers.Resource(init_fn) \
+            .add_args(1, 2) \
+            .add_kwargs(a3=3, a4=4)
+
+        self.assertEqual(provider(), ((1, 2), {'a3': 3, 'a4': 4}))
+
+    def test_set_args(self):
+        provider = providers.Resource(init_fn) \
+            .add_args(1, 2) \
+            .set_args(3, 4)
+        self.assertEqual(provider.args, tuple([3, 4]))
+
+    def test_clear_args(self):
+        provider = providers.Resource(init_fn) \
+            .add_args(1, 2) \
+            .clear_args()
+        self.assertEqual(provider.args, tuple())
+
+    def test_set_kwargs(self):
+        provider = providers.Resource(init_fn) \
+            .add_kwargs(a1='i1', a2='i2') \
+            .set_kwargs(a3='i3', a4='i4')
+        self.assertEqual(provider.kwargs, {'a3': 'i3', 'a4': 'i4'})
+
+    def test_clear_kwargs(self):
+        provider = providers.Resource(init_fn) \
+            .add_kwargs(a1='i1', a2='i2') \
+            .clear_kwargs()
+        self.assertEqual(provider.kwargs, {})
+
+    def test_call_overridden(self):
+        provider = providers.Resource(init_fn, 1)
+        overriding_provider1 = providers.Resource(init_fn, 2)
+        overriding_provider2 = providers.Resource(init_fn, 3)
+
+        provider.override(overriding_provider1)
+        provider.override(overriding_provider2)
+
+        instance1 = provider()
+        instance2 = provider()
+
+        self.assertIs(instance1, instance2)
+        self.assertEqual(instance1, ((3,), {}))
+        self.assertEqual(instance2, ((3,), {}))
+
+    def test_deepcopy(self):
+        provider = providers.Resource(init_fn, 1, 2, a3=3, a4=4)
+
+        provider_copy = providers.deepcopy(provider)
+
+        self.assertIsNot(provider, provider_copy)
+        self.assertEqual(provider.args, provider_copy.args)
+        self.assertEqual(provider.kwargs, provider_copy.kwargs)
+        self.assertIsInstance(provider, providers.Resource)
+
+    def test_deepcopy_initialized(self):
+        provider = providers.Resource(init_fn)
+        provider.init()
+
+        with self.assertRaises(errors.Error):
+            providers.deepcopy(provider)
+
+    def test_deepcopy_from_memo(self):
+        provider = providers.Resource(init_fn)
+        provider_copy_memo = providers.Resource(init_fn)
+
+        provider_copy = providers.deepcopy(
+            provider,
+            memo={id(provider): provider_copy_memo},
+        )
+
+        self.assertIs(provider_copy, provider_copy_memo)
+
+    def test_deepcopy_args(self):
+        provider = providers.Resource(init_fn)
+        dependent_provider1 = providers.Factory(list)
+        dependent_provider2 = providers.Factory(dict)
+
+        provider.add_args(dependent_provider1, dependent_provider2)
+
+        provider_copy = providers.deepcopy(provider)
+        dependent_provider_copy1 = provider_copy.args[0]
+        dependent_provider_copy2 = provider_copy.args[1]
+
+        self.assertNotEqual(provider.args, provider_copy.args)
+
+        self.assertIs(dependent_provider1.cls, dependent_provider_copy1.cls)
+        self.assertIsNot(dependent_provider1, dependent_provider_copy1)
+
+        self.assertIs(dependent_provider2.cls, dependent_provider_copy2.cls)
+        self.assertIsNot(dependent_provider2, dependent_provider_copy2)
+
+    def test_deepcopy_kwargs(self):
+        provider = providers.Resource(init_fn)
+        dependent_provider1 = providers.Factory(list)
+        dependent_provider2 = providers.Factory(dict)
+
+        provider.add_kwargs(d1=dependent_provider1, d2=dependent_provider2)
+
+        provider_copy = providers.deepcopy(provider)
+        dependent_provider_copy1 = provider_copy.kwargs['d1']
+        dependent_provider_copy2 = provider_copy.kwargs['d2']
+
+        self.assertNotEqual(provider.kwargs, provider_copy.kwargs)
+
+        self.assertIs(dependent_provider1.cls, dependent_provider_copy1.cls)
+        self.assertIsNot(dependent_provider1, dependent_provider_copy1)
+
+        self.assertIs(dependent_provider2.cls, dependent_provider_copy2.cls)
+        self.assertIsNot(dependent_provider2, dependent_provider_copy2)
+
+    def test_deepcopy_overridden(self):
+        provider = providers.Resource(init_fn)
+        object_provider = providers.Object(object())
+
+        provider.override(object_provider)
+
+        provider_copy = providers.deepcopy(provider)
+        object_provider_copy = provider_copy.overridden[0]
+
+        self.assertIsNot(provider, provider_copy)
+        self.assertEqual(provider.args, provider_copy.args)
+        self.assertIsInstance(provider, providers.Resource)
+
+        self.assertIsNot(object_provider, object_provider_copy)
+        self.assertIsInstance(object_provider_copy, providers.Object)
+
+    def test_deepcopy_with_sys_streams(self):
+        provider = providers.Resource(init_fn)
+        provider.add_args(sys.stdin, sys.stdout, sys.stderr)
+
+        provider_copy = providers.deepcopy(provider)
+
+        self.assertIsNot(provider, provider_copy)
+        self.assertIsInstance(provider_copy, providers.Resource)
+        self.assertIs(provider.args[0], sys.stdin)
+        self.assertIs(provider.args[1], sys.stdout)
+        self.assertIs(provider.args[2], sys.stderr)
+
+    def test_repr(self):
+        provider = providers.Resource(init_fn)
+
+        self.assertEqual(
+            repr(provider),
+            'Resource({0}, initialized={1})'.format(
+                init_fn,
+                provider.initialized,
+            )
+        )

tox.ini

@@ -5,6 +5,8 @@ envlist=
 [testenv]
 deps=
     unittest2
+    # TODO: Hotfix, remove when fixed https://github.com/aio-libs/aiohttp/issues/5107
+    typing_extensions
 extras=
     yaml
     flask
@@ -28,6 +30,8 @@ commands=
     coveralls
 
 [testenv:py27]
+deps=
+    unittest2
 extras=
     yaml
     flask
@@ -35,6 +39,8 @@ commands=
     unit2 discover -s tests/unit -p test_*_py2_py3.py
 
 [testenv:py34]
+deps=
+    unittest2
 extras=
     flask
 commands=
@@ -48,6 +54,8 @@ commands=
     unit2 discover -s tests/unit -p test_*_py3.py
 
 [testenv:pypy]
+deps=
+    unittest2
 extras=
     yaml
     flask