Avoid redundant response release-connection calls

Author: rodrigo.nogueira

CHANGES/10089.bugfix.rst

@@ -0,0 +1,2 @@
+Reduced redundant ``ClientResponse._release_connection()`` invocations so
+successful requests now trigger a single release-path call per response.

aiohttp/client_reqrep.py

@@ -510,7 +510,8 @@ def release(self) -> None:
         self._closed = True
 
         self._cleanup_writer()
-        self._release_connection()
+        if self._connection is not None:
+            self._release_connection()
 
     @property
     def ok(self) -> bool:
@@ -558,7 +559,8 @@ async def _wait_released(self) -> None:
                     and task.cancelling()
                 ):
                     raise
-        self._release_connection()
+        if self._connection is not None:
+            self._release_connection()
 
     def _cleanup_writer(self) -> None:
         if self.__writer is not None:
@@ -583,7 +585,8 @@ async def wait_for_close(self) -> None:
                     and task.cancelling()
                 ):
                     raise
-        self.release()
+        if not self._released:
+            self.release()
 
     async def read(self) -> bytes:
         """Read response payload."""

tests/test_client_functional.py

@@ -370,6 +370,26 @@ async def handler(request: web.Request) -> web.Response:
     assert 1 == len(client._session.connector._conns)
 
 
+async def test_release_connection_called_once_per_request(
+    aiohttp_client: AiohttpClient, mocker: MockerFixture
+) -> None:
+    async def handler(request: web.Request) -> web.Response:
+        await request.read()
+        return web.Response(body=b"OK")
+
+    app = web.Application()
+    app.router.add_route("GET", "/", handler)
+    client = await aiohttp_client(app)
+
+    spy = mocker.spy(aiohttp.client_reqrep.ClientResponse, "_release_connection")
+    for _ in range(3):
+        async with client.get("/") as resp:
+            await resp.read()
+    await asyncio.sleep(0)
+
+    assert spy.call_count == 3
+
+
 async def test_HTTP_304(aiohttp_client: AiohttpClient) -> None:
     async def handler(request: web.Request) -> web.Response:
         body = await request.read()