Fix setting MQTT socket buffer size with WebsocketWrapper (#117672)

Author: bdraco

homeassistant/components/mqtt/client.py

@@ -540,6 +540,14 @@ def _async_start_misc_loop(self) -> None:
 
     def _increase_socket_buffer_size(self, sock: SocketType) -> None:
         """Increase the socket buffer size."""
+        if not hasattr(sock, "setsockopt") and hasattr(sock, "_socket"):
+            # The WebsocketWrapper does not wrap setsockopt
+            # so we need to get the underlying socket
+            # Remove this once
+            # https://github.com/eclipse/paho.mqtt.python/pull/843
+            # is available.
+            sock = sock._socket  # noqa: SLF001
+
         new_buffer_size = PREFERRED_BUFFER_SIZE
         while True:
             try:

tests/components/mqtt/test_init.py

@@ -4434,6 +4434,43 @@ async def test_server_sock_buffer_size(
     assert "Unable to increase the socket buffer size" in caplog.text
 
 
+@patch("homeassistant.components.mqtt.client.INITIAL_SUBSCRIBE_COOLDOWN", 0.0)
+@patch("homeassistant.components.mqtt.client.DISCOVERY_COOLDOWN", 0.0)
+@patch("homeassistant.components.mqtt.client.SUBSCRIBE_COOLDOWN", 0.0)
+async def test_server_sock_buffer_size_with_websocket(
+    hass: HomeAssistant,
+    mqtt_client_mock: MqttMockPahoClient,
+    mqtt_mock_entry: MqttMockHAClientGenerator,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Test handling the socket buffer size fails."""
+    mqtt_mock = await mqtt_mock_entry()
+    await hass.async_block_till_done()
+    assert mqtt_mock.connected is True
+
+    mqtt_client_mock.loop_misc.return_value = paho_mqtt.MQTT_ERR_SUCCESS
+
+    client, server = socket.socketpair(
+        family=socket.AF_UNIX, type=socket.SOCK_STREAM, proto=0
+    )
+    client.setblocking(False)
+    server.setblocking(False)
+
+    class FakeWebsocket(paho_mqtt.WebsocketWrapper):
+        def _do_handshake(self, *args, **kwargs):
+            pass
+
+    wrapped_socket = FakeWebsocket(client, "127.0.01", 1, False, "/", None)
+
+    with patch.object(client, "setsockopt", side_effect=OSError("foo")):
+        mqtt_client_mock.on_socket_open(mqtt_client_mock, None, wrapped_socket)
+        mqtt_client_mock.on_socket_register_write(
+            mqtt_client_mock, None, wrapped_socket
+        )
+        await hass.async_block_till_done()
+    assert "Unable to increase the socket buffer size" in caplog.text
+
+
 @patch("homeassistant.components.mqtt.client.INITIAL_SUBSCRIBE_COOLDOWN", 0.0)
 @patch("homeassistant.components.mqtt.client.DISCOVERY_COOLDOWN", 0.0)
 @patch("homeassistant.components.mqtt.client.SUBSCRIBE_COOLDOWN", 0.0)