Merge remote-tracking branch 'origin/catalogs_copying'

dependency_injector/catalogs/__init__.py

@@ -1,30 +1,16 @@
 """Dependency injector catalogs package."""
 
 from dependency_injector.catalogs.bundle import CatalogBundle
-
 from dependency_injector.catalogs.dynamic import DynamicCatalog
-
 from dependency_injector.catalogs.declarative import (
     DeclarativeCatalogMetaClass,
     DeclarativeCatalog,
     AbstractCatalog,
 )
-
-
-def override(catalog):
-    """:py:class:`DeclarativeCatalog` overriding decorator.
-
-    :param catalog: Catalog that should be overridden by decorated catalog.
-    :type catalog: :py:class:`DeclarativeCatalog` | :py:class:`DynamicCatalog`
-
-    :return: Declarative catalog's overriding decorator.
-    :rtype: callable(:py:class:`DeclarativeCatalog`)
-    """
-    def decorator(overriding_catalog):
-        """Overriding decorator."""
-        catalog.override(overriding_catalog)
-        return overriding_catalog
-    return decorator
+from dependency_injector.catalogs.utils import (
+    copy,
+    override
+)
 
 
 __all__ = (
@@ -33,5 +19,6 @@ __all__ = (
     'DeclarativeCatalogMetaClass',
     'DeclarativeCatalog',
     'AbstractCatalog',
+    'copy',
     'override',
 )

dependency_injector/catalogs/declarative.py

@@ -4,13 +4,11 @@ import six
 
 from dependency_injector.catalogs.dynamic import DynamicCatalog
 from dependency_injector.catalogs.bundle import CatalogBundle
-
 from dependency_injector.utils import (
     is_provider,
     is_catalog,
     is_declarative_catalog,
 )
-
 from dependency_injector.errors import (
     Error,
     UndefinedProviderError,
@@ -125,7 +123,7 @@ class DeclarativeCatalogMetaClass(type):
         :rtype: None
         """
         if is_provider(value):
-            setattr(cls._catalog, name, value)
+            cls.bind_provider(name, value, _set_as_attribute=False)
         return super(DeclarativeCatalogMetaClass, cls).__setattr__(name, value)
 
     def __delattr__(cls, name):
@@ -350,7 +348,8 @@ class DeclarativeCatalog(object):
     get = get_provider  # Backward compatibility for versions < 0.11.*
 
     @classmethod
-    def bind_provider(cls, name, provider):
+    def bind_provider(cls, name, provider, force=False,
+                      _set_as_attribute=True):
         """Bind provider to catalog with specified name.
 
         :param name: Name of the provider.
@@ -359,14 +358,26 @@ class DeclarativeCatalog(object):
         :param provider: Provider instance.
         :type provider: :py:class:`dependency_injector.providers.Provider`
 
+        :param force: Force binding of provider.
+        :type force: bool
+
         :raise: :py:exc:`dependency_injector.errors.Error`
 
         :rtype: None
         """
-        setattr(cls, name, provider)
+        if cls._catalog.is_provider_bound(provider):
+            bindind_name = cls._catalog.get_provider_bind_name(provider)
+            if bindind_name == name and not force:
+                return
+
+        cls._catalog.bind_provider(name, provider, force)
+        cls.cls_providers[name] = provider
+
+        if _set_as_attribute:
+            setattr(cls, name, provider)
 
     @classmethod
-    def bind_providers(cls, providers):
+    def bind_providers(cls, providers, force=False):
         """Bind providers dictionary to catalog.
 
         :param providers: Dictionary of providers, where key is a name
@@ -374,12 +385,15 @@ class DeclarativeCatalog(object):
         :type providers:
             dict[str, :py:class:`dependency_injector.providers.Provider`]
 
+        :param force: Force binding of providers.
+        :type force: bool
+
         :raise: :py:exc:`dependency_injector.errors.Error`
 
         :rtype: None
         """
         for name, provider in six.iteritems(providers):
-            setattr(cls, name, provider)
+            cls.bind_provider(name, provider, force=force)
 
     @classmethod
     def has_provider(cls, name):
@@ -404,6 +418,7 @@ class DeclarativeCatalog(object):
         :rtype: None
         """
         delattr(cls, name)
+        del cls.cls_providers[name]
 
     @classmethod
     def __getattr__(cls, name):  # pragma: no cover

dependency_injector/catalogs/dynamic.py

@@ -3,13 +3,11 @@
 import six
 
 from dependency_injector.catalogs.bundle import CatalogBundle
-
 from dependency_injector.utils import (
     is_provider,
     ensure_is_provider,
     ensure_is_catalog_bundle,
 )
-
 from dependency_injector.errors import (
     Error,
     UndefinedProviderError,
@@ -213,7 +211,7 @@ class DynamicCatalog(object):
             raise UndefinedProviderError('{0} has no provider with such '
                                          'name - {1}'.format(self, name))
 
-    def bind_provider(self, name, provider):
+    def bind_provider(self, name, provider, force=False):
         """Bind provider to catalog with specified name.
 
         :param name: Name of the provider.
@@ -222,6 +220,9 @@ class DynamicCatalog(object):
         :param provider: Provider instance.
         :type provider: :py:class:`dependency_injector.providers.Provider`
 
+        :param force: Force binding of provider.
+        :type force: bool
+
         :raise: :py:exc:`dependency_injector.errors.Error`
 
         :rtype: None
@@ -233,17 +234,18 @@ class DynamicCatalog(object):
             raise Error('{0} can contain only {1} instances'.format(
                 self, self.__class__.provider_type))
 
-        if name in self.providers:
-            raise Error('Catalog {0} already has provider with '
-                        'such name - {1}'.format(self, name))
-        if provider in self.provider_names:
-            raise Error('Catalog {0} already has such provider '
-                        'instance - {1}'.format(self, provider))
+        if not force:
+            if name in self.providers:
+                raise Error('Catalog {0} already has provider with '
+                            'such name - {1}'.format(self, name))
+            if provider in self.provider_names:
+                raise Error('Catalog {0} already has such provider '
+                            'instance - {1}'.format(self, provider))
 
         self.providers[name] = provider
         self.provider_names[provider] = name
 
-    def bind_providers(self, providers):
+    def bind_providers(self, providers, force=False):
         """Bind providers dictionary to catalog.
 
         :param providers: Dictionary of providers, where key is a name
@@ -251,12 +253,15 @@ class DynamicCatalog(object):
         :type providers:
             dict[str, :py:class:`dependency_injector.providers.Provider`]
 
+        :param force: Force binding of providers.
+        :type force: bool
+
         :raise: :py:exc:`dependency_injector.errors.Error`
 
         :rtype: None
         """
         for name, provider in six.iteritems(providers):
-            self.bind_provider(name, provider)
+            self.bind_provider(name, provider, force)
 
     def has_provider(self, name):
         """Check if there is provider with certain name.

dependency_injector/catalogs/utils.py

@@ -0,0 +1,62 @@
+"""Dependency injector catalog utils."""
+
+import six
+
+from dependency_injector.utils import _copy_providers
+from dependency_injector.errors import UndefinedProviderError
+
+
+def copy(catalog):
+    """:py:class:`DeclarativeCatalog` copying decorator.
+
+    This decorator copy all providers from provided catalog to decorated one.
+    If one of the decorated catalog providers matches to source catalog
+    providers by name, it would be replaced by reference.
+
+    :param catalog: Catalog that should be copied by decorated catalog.
+    :type catalog: :py:class:`dependency_injector.catalogs.DeclarativeCatalog`
+
+    :return: Declarative catalog's copying decorator.
+    :rtype:
+        callable(:py:class:`DeclarativeCatalog`)
+    """
+    def decorator(copied_catalog):
+        """Copying decorator.
+
+        :param copied_catalog: Decorated catalog.
+        :type copied_catalog: :py:class:`DeclarativeCatalog`
+
+        :return: Decorated catalog.
+        :rtype:
+            :py:class:`DeclarativeCatalog`
+        """
+        memo = dict()
+        for name, provider in six.iteritems(copied_catalog.cls_providers):
+            try:
+                source_provider = catalog.get_provider(name)
+            except UndefinedProviderError:
+                pass
+            else:
+                memo[id(source_provider)] = provider
+
+        copied_catalog.bind_providers(_copy_providers(catalog.providers, memo),
+                                      force=True)
+
+        return copied_catalog
+    return decorator
+
+
+def override(catalog):
+    """:py:class:`DeclarativeCatalog` overriding decorator.
+
+    :param catalog: Catalog that should be overridden by decorated catalog.
+    :type catalog: :py:class:`DeclarativeCatalog`
+
+    :return: Declarative catalog's overriding decorator.
+    :rtype: callable(:py:class:`DeclarativeCatalog`)
+    """
+    def decorator(overriding_catalog):
+        """Overriding decorator."""
+        catalog.override(overriding_catalog)
+        return overriding_catalog
+    return decorator

dependency_injector/providers/__init__.py

@@ -6,8 +6,6 @@ from dependency_injector.providers.base import (
     Static,
     StaticProvider,
     ExternalDependency,
-    OverridingContext,
-    override,
 )
 from dependency_injector.providers.callable import (
     Callable,
@@ -29,6 +27,10 @@ from dependency_injector.providers.config import (
     Config,
     ChildConfig,
 )
+from dependency_injector.providers.utils import (
+    OverridingContext,
+    override,
+)
 
 
 __all__ = (

dependency_injector/providers/base.py

@@ -2,8 +2,8 @@
 
 import six
 
+from dependency_injector.providers.utils import OverridingContext
 from dependency_injector.errors import Error
-
 from dependency_injector.utils import (
     is_provider,
     ensure_is_provider,
@@ -356,67 +356,3 @@ class ExternalDependency(Provider):
         return represent_provider(provider=self, provides=self.instance_of)
 
     __repr__ = __str__
-
-
-class OverridingContext(object):
-    """Provider overriding context.
-
-    :py:class:`OverridingContext` is used by :py:meth:`Provider.override` for
-    implemeting ``with`` contexts. When :py:class:`OverridingContext` is
-    closed, overriding that was created in this context is dropped also.
-
-    .. code-block:: python
-
-        with provider.override(another_provider):
-            assert provider.is_overridden
-        assert not provider.is_overridden
-    """
-
-    def __init__(self, overridden, overriding):
-        """Initializer.
-
-        :param overridden: Overridden provider.
-        :type overridden: :py:class:`Provider`
-
-        :param overriding: Overriding provider.
-        :type overriding: :py:class:`Provider`
-        """
-        self.overridden = overridden
-        self.overriding = overriding
-
-    def __enter__(self):
-        """Do nothing."""
-        return self.overriding
-
-    def __exit__(self, *_):
-        """Exit overriding context."""
-        self.overridden.reset_last_overriding()
-
-
-def override(overridden):
-    """Decorator for overriding providers.
-
-    This decorator overrides ``overridden`` provider by decorated one.
-
-    .. code-block:: python
-
-        @Factory
-        class SomeClass(object):
-            pass
-
-
-        @override(SomeClass)
-        @Factory
-        class ExtendedSomeClass(SomeClass.cls):
-            pass
-
-    :param overridden: Provider that should be overridden.
-    :type overridden: :py:class:`Provider`
-
-    :return: Overriding provider.
-    :rtype: :py:class:`Provider`
-    """
-    def decorator(overriding):
-        overridden.override(overriding)
-        return overriding
-    return decorator

dependency_injector/providers/callable.py

@@ -3,14 +3,11 @@
 import six
 
 from dependency_injector.providers.base import Provider
-
 from dependency_injector.injections import (
     _parse_args_injections,
     _parse_kwargs_injections,
 )
-
 from dependency_injector.utils import represent_provider
-
 from dependency_injector.errors import Error
 
 

dependency_injector/providers/config.py

@@ -3,10 +3,8 @@
 import six
 
 from dependency_injector.providers.base import Provider
-
-from dependency_injector.errors import Error
-
 from dependency_injector.utils import represent_provider
+from dependency_injector.errors import Error
 
 
 @six.python_2_unicode_compatible

dependency_injector/providers/creational.py

@@ -1,13 +1,11 @@
 """Dependency injector creational providers."""
 
 from dependency_injector.providers.callable import Callable
-
 from dependency_injector.utils import (
     is_attribute_injection,
     is_method_injection,
     GLOBAL_LOCK,
 )
-
 from dependency_injector.errors import Error
 
 

dependency_injector/providers/utils.py

@@ -0,0 +1,65 @@
+"""Dependency injector provider utils."""
+
+
+class OverridingContext(object):
+    """Provider overriding context.
+
+    :py:class:`OverridingContext` is used by :py:meth:`Provider.override` for
+    implemeting ``with`` contexts. When :py:class:`OverridingContext` is
+    closed, overriding that was created in this context is dropped also.
+
+    .. code-block:: python
+
+        with provider.override(another_provider):
+            assert provider.is_overridden
+        assert not provider.is_overridden
+    """
+
+    def __init__(self, overridden, overriding):
+        """Initializer.
+
+        :param overridden: Overridden provider.
+        :type overridden: :py:class:`Provider`
+
+        :param overriding: Overriding provider.
+        :type overriding: :py:class:`Provider`
+        """
+        self.overridden = overridden
+        self.overriding = overriding
+
+    def __enter__(self):
+        """Do nothing."""
+        return self.overriding
+
+    def __exit__(self, *_):
+        """Exit overriding context."""
+        self.overridden.reset_last_overriding()
+
+
+def override(overridden):
+    """Decorator for overriding providers.
+
+    This decorator overrides ``overridden`` provider by decorated one.
+
+    .. code-block:: python
+
+        @Factory
+        class SomeClass(object):
+            pass
+
+
+        @override(SomeClass)
+        @Factory
+        class ExtendedSomeClass(SomeClass.cls):
+            pass
+
+    :param overridden: Provider that should be overridden.
+    :type overridden: :py:class:`Provider`
+
+    :return: Overriding provider.
+    :rtype: :py:class:`Provider`
+    """
+    def decorator(overriding):
+        overridden.override(overriding)
+        return overriding
+    return decorator

dependency_injector/utils.py

@@ -1,6 +1,8 @@
 """Utils module."""
 
 import sys
+import copy
+import types
 import threading
 
 import six
@@ -20,6 +22,12 @@ if _IS_PYPY or six.PY3:  # pragma: no cover
 else:  # pragma: no cover
     _OBJECT_INIT = None
 
+if six.PY2:  # pragma: no cover
+    copy._deepcopy_dispatch[types.MethodType] = \
+        lambda obj, memo: type(obj)(obj.im_func,
+                                    copy.deepcopy(obj.im_self, memo),
+                                    obj.im_class)
+
 
 def is_provider(instance):
     """Check if instance is provider instance.
@@ -245,3 +253,8 @@ def fetch_cls_init(cls):
         return None
     else:
         return cls_init
+
+
+def _copy_providers(providers, memo=None):
+    """Make full copy of providers dictionary."""
+    return copy.deepcopy(providers, memo)

docs/main/changelog.rst

@@ -9,7 +9,7 @@ follows `Semantic versioning`_
 
 Development version
 -------------------
-- No features.
+- Add ``@copy`` decorator for copying declarative catalog providers.
 
 1.15.2
 ------

examples/stories/movie_lister/apps_db_csv.py

@@ -0,0 +1,76 @@
+"""A naive example of dependency injection in Python.
+
+Example implementation of dependency injection in Python from Martin Fowler's
+article about dependency injection and inversion of control:
+
+http://www.martinfowler.com/articles/injection.html
+
+This mini application uses ``movies`` library, that is configured to work with
+csv file movies database.
+"""
+
+import sqlite3
+
+from dependency_injector import catalogs
+from dependency_injector import providers
+from dependency_injector import injections
+
+from movies import MoviesModule
+from movies import finders
+
+from settings import MOVIES_CSV_PATH
+from settings import MOVIES_DB_PATH
+
+
+class ApplicationModule(catalogs.DeclarativeCatalog):
+    """Catalog of application component providers."""
+
+    database = providers.Singleton(sqlite3.connect, MOVIES_DB_PATH)
+
+
+@catalogs.copy(MoviesModule)
+class DbMoviesModule(MoviesModule):
+    """Customized catalog of movies module component providers."""
+
+    movie_finder = providers.Factory(finders.SqliteMovieFinder,
+                                     *MoviesModule.movie_finder.injections,
+                                     database=ApplicationModule.database)
+
+
+@catalogs.copy(MoviesModule)
+class CsvMoviesModule(MoviesModule):
+    """Customized catalog of movies module component providers."""
+
+    movie_finder = providers.Factory(finders.CsvMovieFinder,
+                                     *MoviesModule.movie_finder.injections,
+                                     csv_file=MOVIES_CSV_PATH,
+                                     delimeter=',')
+
+
+@injections.inject(db_movie_lister=DbMoviesModule.movie_lister)
+@injections.inject(csv_movie_lister=CsvMoviesModule.movie_lister)
+def main(db_movie_lister, csv_movie_lister):
+    """Main function.
+
+    This program prints info about all movies that were directed by different
+    persons and then prints all movies that were released in 2015.
+
+    :param db_movie_lister: Database movie lister instance
+    :type db_movie_lister: movies.listers.MovieLister
+
+    :param csv_movie_lister: Database movie lister instance
+    :type csv_movie_lister: movies.listers.MovieLister
+    """
+    print db_movie_lister.movies_directed_by('Francis Lawrence')
+    print db_movie_lister.movies_directed_by('Patricia Riggen')
+    print db_movie_lister.movies_directed_by('JJ Abrams')
+    print db_movie_lister.movies_released_in(2015)
+
+    print csv_movie_lister.movies_directed_by('Francis Lawrence')
+    print csv_movie_lister.movies_directed_by('Patricia Riggen')
+    print csv_movie_lister.movies_directed_by('JJ Abrams')
+    print csv_movie_lister.movies_released_in(2015)
+
+
+if __name__ == '__main__':
+    main()

tests/catalogs/test_declarative.py

@@ -29,6 +29,17 @@ class DeclarativeCatalogTests(unittest.TestCase):
 
     def test_cls_providers(self):
         """Test `di.DeclarativeCatalog.cls_providers` contents."""
+        class CatalogA(catalogs.DeclarativeCatalog):
+            """Test catalog A."""
+
+            p11 = providers.Provider()
+            p12 = providers.Provider()
+
+        class CatalogB(CatalogA):
+            """Test catalog B."""
+
+            p21 = providers.Provider()
+            p22 = providers.Provider()
         self.assertDictEqual(CatalogA.cls_providers,
                              dict(p11=CatalogA.p11,
                                   p12=CatalogA.p12))
@@ -71,6 +82,14 @@ class DeclarativeCatalogTests(unittest.TestCase):
         del CatalogA.px
         del CatalogA.py
 
+    def test_bind_existing_provider(self):
+        """Test setting of provider via bind_provider() to catalog."""
+        with self.assertRaises(errors.Error):
+            CatalogA.p11 = providers.Provider()
+
+        with self.assertRaises(errors.Error):
+            CatalogA.bind_provider('p11', providers.Provider())
+
     def test_bind_provider_with_valid_provided_type(self):
         """Test setting of provider with provider type restriction."""
         class SomeProvider(providers.Provider):
@@ -350,3 +369,62 @@ class TestCatalogWithProvidingCallbacks(unittest.TestCase):
         auth_service = Services.auth()
 
         self.assertIsInstance(auth_service, ExtendedAuthService)
+
+
+class CopyingTests(unittest.TestCase):
+    """Declarative catalogs copying tests."""
+
+    def test_copy(self):
+        """Test catalog providers copying."""
+        @catalogs.copy(CatalogA)
+        class CatalogA1(CatalogA):
+            pass
+
+        @catalogs.copy(CatalogA)
+        class CatalogA2(CatalogA):
+            pass
+
+        self.assertIsNot(CatalogA.p11, CatalogA1.p11)
+        self.assertIsNot(CatalogA.p12, CatalogA1.p12)
+
+        self.assertIsNot(CatalogA.p11, CatalogA2.p11)
+        self.assertIsNot(CatalogA.p12, CatalogA2.p12)
+
+        self.assertIsNot(CatalogA1.p11, CatalogA2.p11)
+        self.assertIsNot(CatalogA1.p12, CatalogA2.p12)
+
+    def test_copy_with_replacing(self):
+        """Test catalog providers copying."""
+        class CatalogA(catalogs.DeclarativeCatalog):
+            p11 = providers.Value(0)
+            p12 = providers.Factory(dict, p11=p11)
+
+        @catalogs.copy(CatalogA)
+        class CatalogA1(CatalogA):
+            p11 = providers.Value(1)
+            p13 = providers.Value(11)
+
+        @catalogs.copy(CatalogA)
+        class CatalogA2(CatalogA):
+            p11 = providers.Value(2)
+            p13 = providers.Value(22)
+
+        self.assertIsNot(CatalogA.p11, CatalogA1.p11)
+        self.assertIsNot(CatalogA.p12, CatalogA1.p12)
+
+        self.assertIsNot(CatalogA.p11, CatalogA2.p11)
+        self.assertIsNot(CatalogA.p12, CatalogA2.p12)
+
+        self.assertIsNot(CatalogA1.p11, CatalogA2.p11)
+        self.assertIsNot(CatalogA1.p12, CatalogA2.p12)
+
+        self.assertIs(CatalogA.p12.injections[0].injectable, CatalogA.p11)
+        self.assertIs(CatalogA1.p12.injections[0].injectable, CatalogA1.p11)
+        self.assertIs(CatalogA2.p12.injections[0].injectable, CatalogA2.p11)
+
+        self.assertEqual(CatalogA.p12(), dict(p11=0))
+        self.assertEqual(CatalogA1.p12(), dict(p11=1))
+        self.assertEqual(CatalogA2.p12(), dict(p11=2))
+
+        self.assertEqual(CatalogA1.p13(), 11)
+        self.assertEqual(CatalogA2.p13(), 22)

tests/catalogs/test_dynamic.py

@@ -41,6 +41,17 @@ class DynamicCatalogTests(unittest.TestCase):
         self.assertIs(self.catalog.py, py)
         self.assertIs(self.catalog.get_provider('py'), py)
 
+    def test_bind_existing_provider(self):
+        """Test setting of provider via bind_provider() to catalog."""
+        with self.assertRaises(errors.Error):
+            self.catalog.bind_provider('p1', providers.Factory(object))
+
+    def test_force_bind_existing_provider(self):
+        """Test setting of provider via bind_provider() to catalog."""
+        p1 = providers.Factory(object)
+        self.catalog.bind_provider('p1', p1, force=True)
+        self.assertIs(self.catalog.p1, p1)
+
     def test_bind_provider_with_valid_provided_type(self):
         """Test setting of provider with provider type restriction."""
         class SomeProvider(providers.Provider):
@@ -99,6 +110,17 @@ class DynamicCatalogTests(unittest.TestCase):
         self.assertIs(self.catalog.py, py)
         self.assertIs(self.catalog.get_provider('py'), py)
 
+    def test_bind_providers_with_existing(self):
+        """Test setting of provider via bind_providers() to catalog."""
+        with self.assertRaises(errors.Error):
+            self.catalog.bind_providers(dict(p1=providers.Factory(object)))
+
+    def test_bind_providers_force(self):
+        """Test setting of provider via bind_providers() to catalog."""
+        p1 = providers.Factory(object)
+        self.catalog.bind_providers(dict(p1=p1), force=True)
+        self.assertIs(self.catalog.p1, p1)
+
     def test_setattr(self):
         """Test setting of providers via attributes to catalog."""
         px = providers.Provider()