updating concept

examples/concept.py

@@ -2,7 +2,7 @@
 Concept example of objects catalogs.
 """
 
-import objects
+from objects import Catalog, Singleton, NewInstance, InitArg, Attribute
 import sqlite3
 
 
@@ -19,29 +19,30 @@ class B(object):
 
 
 # Catalog of objects providers.
-class Catalog(objects.Catalog):
+class AppCatalog(Catalog):
     """
     Objects catalog.
     """
 
-    database = objects.Singleton(provides=sqlite3.Connection,
-                                 database='example.db')
+    database = Singleton(sqlite3.Connection,
+                         InitArg('database', ':memory:'),
+                         Attribute('row_factory', sqlite3.Row))
     """ :type: (objects.Provider) -> sqlite3.Connection """
 
-    object_a = objects.NewInstance(provides=A,
-                                   db=database)
+    object_a = NewInstance(A,
+                           InitArg('db', database))
     """ :type: (objects.Provider) -> A """
 
-    object_b = objects.NewInstance(provides=B,
-                                   a=object_a,
-                                   db=database)
+    object_b = NewInstance(B,
+                           InitArg('a', object_a),
+                           InitArg('db', database))
     """ :type: (objects.Provider) -> B """
 
 
 # Catalog injection into consumer class.
 class Consumer(object):
-    catalog = Catalog(Catalog.object_a,
-                      Catalog.object_b)
+    catalog = AppCatalog(AppCatalog.object_a,
+                         AppCatalog.object_b)
 
     def return_a_b(self):
         return (self.catalog.object_a(),
@@ -51,8 +52,8 @@ a1, b1 = Consumer().return_a_b()
 
 
 # Catalog static provides.
-a2 = Catalog.object_a()
-b2 = Catalog.object_b()
+a2 = AppCatalog.object_a()
+b2 = AppCatalog.object_b()
 
 # Some asserts.
 assert a1 is not a2

examples/concept_v1.py

@@ -1,61 +0,0 @@
-"""
-Concept example of objects catalogs.
-"""
-
-from objects import Catalog, Singleton, NewInstance, KwArg, Attribute
-import sqlite3
-
-
-# Some example classes.
-class A(object):
-    def __init__(self, db):
-        self.db = db
-
-
-class B(object):
-    def __init__(self, a, db):
-        self.a = a
-        self.db = db
-
-
-# Catalog of objects providers.
-class AppCatalog(Catalog):
-    """
-    Objects catalog.
-    """
-
-    database = Singleton(provides=sqlite3.Connection,
-                         database=KwArg('example.db'),
-                         row_factory=Attribute(sqlite3.Row))
-    """ :type: (Provider) -> sqlite3.Connection """
-
-    object_a = NewInstance(provides=A,
-                           db=KwArg(database))
-    """ :type: (Provider) -> A """
-
-    object_b = NewInstance(provides=B,
-                           a=KwArg(object_a),
-                           db=KwArg(database))
-    """ :type: (Provider) -> B """
-
-
-# Catalog injection into consumer class.
-class Consumer(object):
-    catalog = AppCatalog(AppCatalog.object_a,
-                         AppCatalog.object_b)
-
-    def return_a_b(self):
-        return (self.catalog.object_a(),
-                self.catalog.object_b())
-
-a1, b1 = Consumer().return_a_b()
-
-
-# Catalog static provides.
-a2 = AppCatalog.object_a()
-b2 = AppCatalog.object_b()
-
-# Some asserts.
-assert a1 is not a2
-assert b1 is not b2
-assert a1.db is a2.db is b1.db is b2.db

examples/concept_v2.py

@@ -1,61 +0,0 @@
-"""
-Concept example of objects catalogs.
-"""
-
-from objects import Catalog, Singleton, NewInstance, KwArg, Attribute
-import sqlite3
-
-
-# Some example classes.
-class A(object):
-    def __init__(self, db):
-        self.db = db
-
-
-class B(object):
-    def __init__(self, a, db):
-        self.a = a
-        self.db = db
-
-
-# Catalog of objects providers.
-class AppCatalog(Catalog):
-    """
-    Objects catalog.
-    """
-
-    database = Singleton(sqlite3.Connection,
-                         KwArg('database', ':memory:'),
-                         Attribute('row_factory', sqlite3.Row))
-    """ :type: (objects.Provider) -> sqlite3.Connection """
-
-    object_a = NewInstance(A,
-                           KwArg('db', database))
-    """ :type: (objects.Provider) -> A """
-
-    object_b = NewInstance(B,
-                           KwArg('a', object_a),
-                           KwArg('db', database))
-    """ :type: (objects.Provider) -> B """
-
-
-# Catalog injection into consumer class.
-class Consumer(object):
-    catalog = AppCatalog(AppCatalog.object_a,
-                         AppCatalog.object_b)
-
-    def return_a_b(self):
-        return (self.catalog.object_a(),
-                self.catalog.object_b())
-
-a1, b1 = Consumer().return_a_b()
-
-
-# Catalog static provides.
-a2 = AppCatalog.object_a()
-b2 = AppCatalog.object_b()
-
-# Some asserts.
-assert a1 is not a2
-assert b1 is not b2
-assert a1.db is a2.db is b1.db is b2.db

objects/__init__.py

@@ -5,7 +5,14 @@
 from .catalog import Catalog
 from .std_providers import (Provider, NewInstance, Singleton, Class, Object,
                             Function, Value)
+from .injections import InitArg, Attribute, Method
 
 
-__all__ = ['Catalog', 'Provider', 'NewInstance', 'Singleton', 'Class',
-           'Object', 'Function', 'Value']
+__all__ = ['Catalog',
+
+           # Providers
+           'Provider', 'NewInstance', 'Singleton', 'Class',
+           'Object', 'Function', 'Value',
+
+           # Injections
+           'InitArg', 'Attribute', 'Method']

objects/injections.py

@@ -0,0 +1,43 @@
+"""
+Injections module.
+"""
+
+
+class Injection(object):
+    """
+    Base injection class.
+    """
+
+    def __init__(self, name, injectable):
+        """
+        Initializer.
+        """
+        self.name = name
+        self.injectable = injectable
+
+    @classmethod
+    def fetch(cls, injections):
+        """
+        Fetches injections of self type from list.
+        """
+        return tuple([injection
+                      for injection in injections
+                      if isinstance(injection, cls)])
+
+
+class InitArg(Injection):
+    """
+    Init argument injection.
+    """
+
+
+class Attribute(Injection):
+    """
+    Attribute injection.
+    """
+
+
+class Method(Injection):
+    """
+    Method injection.
+    """

objects/std_providers.py

@@ -2,6 +2,8 @@
 Standard providers.
 """
 
+from .injections import InitArg, Attribute, Method
+
 
 class Provider(object):
     """
@@ -14,34 +16,54 @@ class Provider(object):
         """
         raise NotImplementedError()
 
+    @staticmethod
+    def prepare_injections(injections):
+        """
+        Prepares injections list to injection.
+        """
+        prepared_injections = dict()
+        for injection in injections:
+            if isinstance(injection.injectable, Provider):
+                value = injection.injectable.__call__()
+            else:
+                value = injection.injectable
+            prepared_injections[injection.name] = value
+        return prepared_injections
+
 
 class NewInstance(Provider):
     """
     New instance providers will create and return new instance on every call.
     """
 
-    def __init__(self, provides, **dependencies):
+    def __init__(self, provides, *injections):
         """
         Initializer.
         """
         self.provides = provides
-        self.dependencies = dependencies
+        self.init_injections = InitArg.fetch(injections)
+        self.attribute_injections = Attribute.fetch(injections)
+        self.method_injections = Method.fetch(injections)
 
     def __call__(self, *args, **kwargs):
         """
         Returns provided instance.
         """
-        for name, dependency in self.dependencies.iteritems():
-            if name in kwargs:
-                continue
+        init_injections = Provider.prepare_injections(self.init_injections)
+        init_injections.update(kwargs)
 
-            if isinstance(dependency, Provider):
-                value = dependency.__call__()
-            else:
-                value = dependency
+        provided = self.provides(*args, **init_injections)
 
-            kwargs[name] = value
-        return self.provides(*args, **kwargs)
+        attribute_injections = Provider.prepare_injections(
+            self.attribute_injections)
+        for name, injectable in attribute_injections.iteritems():
+            setattr(provided, name, injectable)
+
+        method_injections = Provider.prepare_injections(self.method_injections)
+        for name, injectable in method_injections.iteritems():
+            getattr(provided, name)(injectable)
+
+        return provided
 
 
 class Singleton(NewInstance):