Wrap TCP request reading in async_timeout.timeout() (#339)

There have recently been [reports of `RuntimeError: coroutine ignored
GeneratorExit`] which are presumably triggered by timeouts on the
socket, without being raised as `TimeoutError`.  This case seems to be
mitigated by timing out the request after a default of 10 seconds which
doesn't give `GeneratorExit` - triggered by something yet unknown -
enough time to surface.

[reports of `RuntimeError: coroutine ignored GeneratorExit`]: robbinjanssen/home-assistant-omnik-inverter#116

omnikinverter/omnikinverter.py

@@ -137,16 +137,24 @@ async def tcp_request(self) -> dict[str, Any]:
             raise OmnikInverterAuthError(msg)
 
         try:
-            reader, writer = await asyncio.open_connection(self.host, self.tcp_port)
+            async with async_timeout.timeout(self.request_timeout):
+                reader, writer = await asyncio.open_connection(self.host, self.tcp_port)
         except OSError as exception:
             msg = "Failed to open a TCP connection to the Omnik Inverter device"
             raise OmnikInverterConnectionError(msg) from exception
+        except asyncio.TimeoutError as exception:  # pragma: no cover
+            msg = "Timeout occurred while connecting to the Omnik Inverter device"
+            raise OmnikInverterConnectionError(msg) from exception
 
         try:
-            writer.write(tcp.create_information_request(self.serial_number))
-            await writer.drain()
+            async with async_timeout.timeout(self.request_timeout):
+                writer.write(tcp.create_information_request(self.serial_number))
+                await writer.drain()
 
-            raw_msg = await reader.read(1024)
+                raw_msg = await reader.read(1024)
+        except asyncio.TimeoutError as exception:
+            msg = "Timeout occurred while communicating with the Omnik Inverter device"
+            raise OmnikInverterConnectionError(msg) from exception
         finally:
             writer.close()
             try:

tests/test_tcp_models.py

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import struct
+import time
 from socket import SHUT_RDWR, SO_LINGER, SOL_SOCKET, socket
 from threading import Thread
 from typing import TYPE_CHECKING
@@ -403,13 +404,43 @@ def close_immediately(conn: socket) -> None:
         assert await client.inverter()
 
     assert (
-        excinfo.value.args[0]
+        str(excinfo.value)
         == "Failed to communicate with the Omnik Inverter device over TCP"
     )
 
     await server_exit
 
 
+async def test_communication_timeout() -> None:
+    """Test on timed out connection attempt - TCP source."""
+    serial_number = 1
+
+    def long_timeout(conn: socket) -> None:
+        """Close the connection and send RST."""
+        time.sleep(0.2)
+        conn.close()
+
+    (server_exit, port) = tcp_server(serial_number, long_timeout)
+
+    client = OmnikInverter(
+        host="localhost",
+        source_type="tcp",
+        serial_number=serial_number,
+        tcp_port=port,
+        request_timeout=0.1,
+    )
+
+    with pytest.raises(OmnikInverterConnectionError) as excinfo:
+        assert await client.inverter()
+
+    assert (
+        str(excinfo.value)
+        == "Timeout occurred while communicating with the Omnik Inverter device"
+    )
+
+    await server_exit
+
+
 async def test_connection_failed() -> None:
     """Test on failed connection attempt - TCP source."""
     serial_number = 1