Allow WS queue to temporarily peak (#34175)

* Allow WS queue to temporarily peak

* Remove unused code

tests/components/websocket_api/test_http.py

@@ -0,0 +1,66 @@
+"""Test Websocket API http module."""
+from datetime import timedelta
+
+from aiohttp import WSMsgType
+from asynctest import patch
+import pytest
+
+from homeassistant.components.websocket_api import const, http
+from homeassistant.util.dt import utcnow
+
+from tests.common import async_fire_time_changed
+
+
+@pytest.fixture
+def mock_low_queue():
+    """Mock a low queue."""
+    with patch("homeassistant.components.websocket_api.http.MAX_PENDING_MSG", 5):
+        yield
+
+
+@pytest.fixture
+def mock_low_peak():
+    """Mock a low queue."""
+    with patch("homeassistant.components.websocket_api.http.PENDING_MSG_PEAK", 5):
+        yield
+
+
+async def test_pending_msg_overflow(hass, mock_low_queue, websocket_client):
+    """Test get_panels command."""
+    for idx in range(10):
+        await websocket_client.send_json({"id": idx + 1, "type": "ping"})
+    msg = await websocket_client.receive()
+    assert msg.type == WSMsgType.close
+
+
+async def test_pending_msg_peak(hass, mock_low_peak, hass_ws_client, caplog):
+    """Test pending msg overflow command."""
+    orig_handler = http.WebSocketHandler
+    instance = None
+
+    def instantiate_handler(*args):
+        nonlocal instance
+        instance = orig_handler(*args)
+        return instance
+
+    with patch(
+        "homeassistant.components.websocket_api.http.WebSocketHandler",
+        instantiate_handler,
+    ):
+        websocket_client = await hass_ws_client()
+
+    # Kill writer task and fill queue past peak
+    for _ in range(5):
+        instance._to_write.put_nowait(None)
+
+    # Trigger the peak check
+    instance._send_message({})
+
+    async_fire_time_changed(
+        hass, utcnow() + timedelta(seconds=const.PENDING_MSG_PEAK_TIME + 1)
+    )
+
+    msg = await websocket_client.receive()
+    assert msg.type == WSMsgType.close
+
+    assert "Client unable to keep up with pending messages" in caplog.text