Implement attribute injections and add tests

src/dependency_injector/providers.pxd

@@ -438,17 +438,46 @@ cdef inline void __async_prepare_args_kwargs_callback(object future):
 
 @cython.boundscheck(False)
 @cython.wraparound(False)
-cdef inline object __inject_attributes(
-        object instance,
-        tuple attributes,
-        int attributes_len,
-):
+cdef inline object __provide_attributes(tuple attributes, int attributes_len):
     cdef NamedInjection attr_injection
+    cdef dict attribute_injections = {}
+    cdef list awaitables = []
+
     for index in range(attributes_len):
         attr_injection = <NamedInjection>attributes[index]
-        setattr(instance,
-                __get_name(attr_injection),
-                __get_value(attr_injection))
+        name = __get_name(attr_injection)
+        value = __get_value(attr_injection)
+        attribute_injections[name] = value
+        if __isawaitable(value):
+            awaitables.append((name, value))
+
+    if awaitables:
+        return __awaitable_args_kwargs_future(attribute_injections, awaitables)
+
+    return attribute_injections
+
+
+cdef inline object __async_inject_attributes(future_instance, future_attributes):
+    future_result = asyncio.Future()
+
+    future = asyncio.Future()
+    future.set_result(future_result)
+
+    attributes_ready = asyncio.gather(future, future_instance, future_attributes)
+    attributes_ready.add_done_callback(__async_inject_attributes_callback)
+    asyncio.ensure_future(attributes_ready)
+
+    return future_result
+
+cdef inline void __async_inject_attributes_callback(future):
+    future_result, instance, attributes = future.result()
+    __inject_attributes(instance, attributes)
+    future_result.set_result(instance)
+
+
+cdef inline void __inject_attributes(object instance, dict attributes):
+    for name, value in attributes.items():
+        setattr(instance, name, value)
 
 
 cdef inline object __call(
@@ -485,7 +514,6 @@ cdef inline object __call(
             future.set_result(kwargs)
             kwargs = future
 
-
         future_result = asyncio.Future()
 
         future = asyncio.Future()
@@ -524,9 +552,25 @@ cdef inline object __factory_call(Factory self, tuple args, dict kwargs):
     instance = __callable_call(self.__instantiator, args, kwargs)
 
     if self.__attributes_len > 0:
-        __inject_attributes(instance,
-                            self.__attributes,
-                            self.__attributes_len)
+        attributes = __provide_attributes(self.__attributes, self.__attributes_len)
+
+        instance_awaitable = __isawaitable(instance)
+        attributes_awaitable = __isawaitable(attributes)
+
+        if instance_awaitable or attributes_awaitable:
+            if not instance_awaitable:
+                future = asyncio.Future()
+                future.set_result(instance)
+                instance = future
+
+            if not attributes_awaitable:
+                future = asyncio.Future()
+                future.set_result(attributes)
+                attributes = future
+
+            return __async_inject_attributes(instance, attributes)
+
+        __inject_attributes(instance, attributes)
 
     return instance
 

tests/unit/providers/test_async_py36.py

@@ -172,3 +172,49 @@ class FactoryTests(AsyncTestCase):
         self.assertIs(service2.client.resource2, RESOURCE2)
 
         self.assertIsNot(service1.client, service2.client)
+
+    def test_attributes_injection(self):
+        class ContainerWithAttributes(containers.DeclarativeContainer):
+            resource1 = providers.Resource(init_resource, providers.Object(RESOURCE1))
+            resource2 = providers.Resource(init_resource, providers.Object(RESOURCE2))
+
+            client = providers.Factory(
+                Client,
+                resource1,
+                resource2=None,
+            )
+            client.add_attributes(resource2=resource2)
+
+            service = providers.Factory(
+                Service,
+                client=None,
+            )
+            service.add_attributes(client=client)
+
+        container = ContainerWithAttributes()
+
+        client1 = self._run(container.client())
+        client2 = self._run(container.client())
+
+        self.assertIsInstance(client1, Client)
+        self.assertIs(client1.resource1, RESOURCE1)
+        self.assertIs(client1.resource2, RESOURCE2)
+
+        self.assertIsInstance(client2, Client)
+        self.assertIs(client2.resource1, RESOURCE1)
+        self.assertIs(client2.resource2, RESOURCE2)
+
+        service1 = self._run(container.service())
+        service2 = self._run(container.service())
+
+        self.assertIsInstance(service1, Service)
+        self.assertIsInstance(service1.client, Client)
+        self.assertIs(service1.client.resource1, RESOURCE1)
+        self.assertIs(service1.client.resource2, RESOURCE2)
+
+        self.assertIsInstance(service2, Service)
+        self.assertIsInstance(service2.client, Client)
+        self.assertIs(service2.client.resource1, RESOURCE1)
+        self.assertIs(service2.client.resource2, RESOURCE2)
+
+        self.assertIsNot(service1.client, service2.client)