fix: handle timeout on connection close (#1)

Author: joshuagruenstein

examples/example.py

@@ -14,7 +14,7 @@ async def example() -> None:
         response = await conn.send_modbus_message(example_message)
 
     assert response is not None, "we expect a response from ReadCoils"
-    print(response.data)
+    print(response.data)  # noqa: T201
 
 
 if __name__ == "__main__":

tcp_modbus_aio/client.py

@@ -6,12 +6,9 @@
 import time
 import uuid
 from dataclasses import dataclass
-from types import TracebackType
-from typing import Any, ClassVar
+from typing import TYPE_CHECKING, Any, ClassVar
 
 from cachetools import TTLCache
-from typing_extensions import Self
-from umodbus.functions import ModbusFunction
 
 from tcp_modbus_aio.exceptions import (
     ModbusCommunicationFailureError,
@@ -24,6 +21,12 @@
     create_function_from_response_pdu,
 )
 
+if TYPE_CHECKING:
+    from types import TracebackType
+
+    from typing_extensions import Self
+    from umodbus.functions import ModbusFunction
+
 
 @dataclass
 class CoilWatchStatus:
@@ -308,7 +311,16 @@ async def clear_tcp_connection(self) -> None:
                 )
 
             self._writer.close()
-            await self._writer.wait_closed()
+
+            try:
+                await self._writer.wait_closed()
+            except TimeoutError:
+                if self.logger is not None:
+                    self.logger.warning(
+                        f"[{self}][clear_tcp_connection] connection close timed out, continuing anyway"
+                    )
+
+                pass
 
         self._reader = None
         self._writer = None