Dev/no lock (#2308)

* Remove async lock in asyncio.Connection.read_response

* Skip concurrent-commands test on non-pooled connections

4 files changed, 29 insertions, 66 deletions

diff --git a/redis/asyncio/cluster.py b/redis/asyncio/cluster.py
index 78dcd05..8d34b9a 100644
--- a/redis/asyncio/cluster.py
+++ b/redis/asyncio/cluster.py
@@ -390,7 +390,7 @@ class RedisCluster(AbstractRedis, AbstractRedisCluster, AsyncRedisClusterCommand
         # regardless of the server type. If this is a primary connection,
         # READONLY would not affect executing write commands.
         await connection.send_command("READONLY")
-        if str_if_bytes(await connection.read_response_without_lock()) != "OK":
+        if str_if_bytes(await connection.read_response()) != "OK":
             raise ConnectionError("READONLY command failed")
 
     def get_nodes(self) -> List["ClusterNode"]:
@@ -866,11 +866,9 @@ class ClusterNode:
     ) -> Any:
         try:
             if NEVER_DECODE in kwargs:
-                response = await connection.read_response_without_lock(
-                    disable_decoding=True
-                )
+                response = await connection.read_response(disable_decoding=True)
             else:
-                response = await connection.read_response_without_lock()
+                response = await connection.read_response()
         except ResponseError:
             if EMPTY_RESPONSE in kwargs:
                 return kwargs[EMPTY_RESPONSE]
diff --git a/redis/asyncio/connection.py b/redis/asyncio/connection.py
index db8c240..16f33e2 100644
--- a/redis/asyncio/connection.py
+++ b/redis/asyncio/connection.py
@@ -671,7 +671,6 @@ class Connection:
         self.set_parser(parser_class)
         self._connect_callbacks: List[weakref.WeakMethod[ConnectCallbackT]] = []
         self._buffer_cutoff = 6000
-        self._lock = asyncio.Lock()
 
     def __repr__(self):
         repr_args = ",".join((f"{k}={v}" for k, v in self.repr_pieces()))
@@ -942,39 +941,6 @@ class Connection:
     async def read_response(self, disable_decoding: bool = False):
         """Read the response from a previously sent command"""
         try:
-            async with self._lock:
-                if self.socket_timeout:
-                    async with async_timeout.timeout(self.socket_timeout):
-                        response = await self._parser.read_response(
-                            disable_decoding=disable_decoding
-                        )
-                else:
-                    response = await self._parser.read_response(
-                        disable_decoding=disable_decoding
-                    )
-        except asyncio.TimeoutError:
-            await self.disconnect()
-            raise TimeoutError(f"Timeout reading from {self.host}:{self.port}")
-        except OSError as e:
-            await self.disconnect()
-            raise ConnectionError(
-                f"Error while reading from {self.host}:{self.port} : {e.args}"
-            )
-        except BaseException:
-            await self.disconnect()
-            raise
-
-        if self.health_check_interval:
-            next_time = asyncio.get_running_loop().time() + self.health_check_interval
-            self.next_health_check = next_time
-
-        if isinstance(response, ResponseError):
-            raise response from None
-        return response
-
-    async def read_response_without_lock(self, disable_decoding: bool = False):
-        """Read the response from a previously sent command"""
-        try:
             if self.socket_timeout:
                 async with async_timeout.timeout(self.socket_timeout):
                     response = await self._parser.read_response(
@@ -1241,7 +1207,6 @@ class UnixDomainSocketConnection(Connection):  # lgtm [py/missing-call-to-init]
         self.set_parser(parser_class)
         self._connect_callbacks = []
         self._buffer_cutoff = 6000
-        self._lock = asyncio.Lock()
 
     def repr_pieces(self) -> Iterable[Tuple[str, Union[str, int]]]:
         pieces = [("path", self.path), ("db", self.db)]
diff --git a/tests/test_asyncio/test_cluster.py b/tests/test_asyncio/test_cluster.py
index e299395..88cfb1f 100644
--- a/tests/test_asyncio/test_cluster.py
+++ b/tests/test_asyncio/test_cluster.py
@@ -120,7 +120,7 @@ async def get_mocked_redis_client(*args, **kwargs) -> RedisCluster:
 def mock_node_resp(node: ClusterNode, response: Any) -> ClusterNode:
     connection = mock.AsyncMock()
     connection.is_connected = True
-    connection.read_response_without_lock.return_value = response
+    connection.read_response.return_value = response
     while node._free:
         node._free.pop()
     node._free.append(connection)
@@ -130,7 +130,7 @@ def mock_node_resp(node: ClusterNode, response: Any) -> ClusterNode:
 def mock_node_resp_exc(node: ClusterNode, exc: Exception) -> ClusterNode:
     connection = mock.AsyncMock()
     connection.is_connected = True
-    connection.read_response_without_lock.side_effect = exc
+    connection.read_response.side_effect = exc
     while node._free:
         node._free.pop()
     node._free.append(connection)
@@ -275,16 +275,12 @@ class TestRedisClusterObj:
         for node in rc.get_nodes():
             assert node.max_connections == 10
 
-        with mock.patch.object(
-            Connection, "read_response_without_lock"
-        ) as read_response_without_lock:
+        with mock.patch.object(Connection, "read_response") as read_response:
 
-            async def read_response_without_lock_mocked(
-                *args: Any, **kwargs: Any
-            ) -> None:
+            async def read_response_mocked(*args: Any, **kwargs: Any) -> None:
                 await asyncio.sleep(10)
 
-            read_response_without_lock.side_effect = read_response_without_lock_mocked
+            read_response.side_effect = read_response_mocked
 
             with pytest.raises(MaxConnectionsError):
                 await asyncio.gather(
@@ -316,10 +312,10 @@ class TestRedisClusterObj:
         assert await r.ping(target_nodes=RedisCluster.PRIMARIES) is True
         for primary in primaries:
             conn = primary._free.pop()
-            assert conn.read_response_without_lock.called is True
+            assert conn.read_response.called is True
         for replica in replicas:
             conn = replica._free.pop()
-            assert conn.read_response_without_lock.called is not True
+            assert conn.read_response.called is not True
 
     async def test_execute_command_node_flag_replicas(self, r: RedisCluster) -> None:
         """
@@ -333,10 +329,10 @@ class TestRedisClusterObj:
         assert await r.ping(target_nodes=RedisCluster.REPLICAS) is True
         for replica in replicas:
             conn = replica._free.pop()
-            assert conn.read_response_without_lock.called is True
+            assert conn.read_response.called is True
         for primary in primaries:
             conn = primary._free.pop()
-            assert conn.read_response_without_lock.called is not True
+            assert conn.read_response.called is not True
 
         await r.close()
 
@@ -348,7 +344,7 @@ class TestRedisClusterObj:
         assert await r.ping(target_nodes=RedisCluster.ALL_NODES) is True
         for node in r.get_nodes():
             conn = node._free.pop()
-            assert conn.read_response_without_lock.called is True
+            assert conn.read_response.called is True
 
     async def test_execute_command_node_flag_random(self, r: RedisCluster) -> None:
         """
@@ -359,7 +355,7 @@ class TestRedisClusterObj:
         called_count = 0
         for node in r.get_nodes():
             conn = node._free.pop()
-            if conn.read_response_without_lock.called is True:
+            if conn.read_response.called is True:
                 called_count += 1
         assert called_count == 1
 
@@ -372,7 +368,7 @@ class TestRedisClusterObj:
         mock_node_resp(def_node, "PONG")
         assert await r.ping() is True
         conn = def_node._free.pop()
-        assert conn.read_response_without_lock.called
+        assert conn.read_response.called
 
     async def test_ask_redirection(self, r: RedisCluster) -> None:
         """
@@ -516,7 +512,7 @@ class TestRedisClusterObj:
         with mock.patch.multiple(
             Connection,
             send_command=mock.DEFAULT,
-            read_response_without_lock=mock.DEFAULT,
+            read_response=mock.DEFAULT,
             _connect=mock.DEFAULT,
             can_read=mock.DEFAULT,
             on_connect=mock.DEFAULT,
@@ -548,7 +544,7 @@ class TestRedisClusterObj:
                 # so we'll mock some of the Connection's functions to allow it
                 execute_command.side_effect = execute_command_mock_first
                 mocks["send_command"].return_value = True
-                mocks["read_response_without_lock"].return_value = "OK"
+                mocks["read_response"].return_value = "OK"
                 mocks["_connect"].return_value = True
                 mocks["can_read"].return_value = False
                 mocks["on_connect"].return_value = True
@@ -857,8 +853,8 @@ class TestClusterRedisCommands:
         node0 = r.get_node(default_host, 7000)
         node1 = r.get_node(default_host, 7001)
         assert await r.cluster_delslots(0, 8192) == [True, True]
-        assert node0._free.pop().read_response_without_lock.called
-        assert node1._free.pop().read_response_without_lock.called
+        assert node0._free.pop().read_response.called
+        assert node1._free.pop().read_response.called
 
         await r.close()
 
@@ -1027,7 +1023,7 @@ class TestClusterRedisCommands:
         node = r.nodes_manager.get_node_from_slot(12182)
         mock_node_resp(node, "OK")
         assert await r.cluster_setslot_stable(12182) is True
-        assert node._free.pop().read_response_without_lock.called
+        assert node._free.pop().read_response.called
 
     @skip_if_redis_enterprise()
     async def test_cluster_replicas(self, r: RedisCluster) -> None:
@@ -1069,7 +1065,7 @@ class TestClusterRedisCommands:
         for res in all_replicas_results.values():
             assert res is True
         for replica in r.get_replicas():
-            assert replica._free.pop().read_response_without_lock.called
+            assert replica._free.pop().read_response.called
 
         await r.close()
 
@@ -1082,7 +1078,7 @@ class TestClusterRedisCommands:
         for res in all_replicas_results.values():
             assert res is True
         for replica in r.get_replicas():
-            assert replica._free.pop().read_response_without_lock.called
+            assert replica._free.pop().read_response.called
 
         await r.close()
 
@@ -2441,8 +2437,8 @@ class TestClusterPipeline:
             mock_node_resp_exc(first_node, AskError(ask_msg))
             mock_node_resp(ask_node, "MOCK_OK")
             res = await pipe.get(key).execute()
-            assert first_node._free.pop().read_response_without_lock.await_count
-            assert ask_node._free.pop().read_response_without_lock.await_count
+            assert first_node._free.pop().read_response.await_count
+            assert ask_node._free.pop().read_response.await_count
             assert res == ["MOCK_OK"]
 
     async def test_moved_redirection_on_slave_with_default(
@@ -2497,7 +2493,7 @@ class TestClusterPipeline:
             executed_on_replica = False
             for node in slot_nodes:
                 if node.server_type == REPLICA:
-                    if node._free.pop().read_response_without_lock.await_count:
+                    if node._free.pop().read_response.await_count:
                         executed_on_replica = True
                         break
             assert executed_on_replica
diff --git a/tests/test_asyncio/test_connection.py b/tests/test_asyncio/test_connection.py
index 419c8a7..674a1b9 100644
--- a/tests/test_asyncio/test_connection.py
+++ b/tests/test_asyncio/test_connection.py
@@ -64,6 +64,10 @@ async def test_socket_param_regression(r):
 
 
 async def test_can_run_concurrent_commands(r):
+    if getattr(r, "connection", None) is not None:
+        # Concurrent commands are only supported on pooled or cluster connections
+        # since there is no synchronization on a single connection.
+        pytest.skip("pool only")
     assert await r.ping() is True
     assert all(await asyncio.gather(*(r.ping() for _ in range(10))))