test: add integration test for custom event round-trip via coordinator_ws

Verifies the full pub/sub cycle: send a custom event via REST
(call.send_call_event), receive it on ConnectionManager.coordinator_ws
through ws.on("custom") listener. Uses asyncio.Event for reliable
timing instead of fixed sleep.

Author: aliev

tests/rtc/coordinator/test_custom_events.py

@@ -0,0 +1,69 @@
+"""
+Integration tests for custom event pub/sub via coordinator WebSocket.
+
+Tests the full round-trip: send a custom event via REST, receive it on the
+coordinator WS through ConnectionManager.coordinator_ws property.
+
+Requires Stream API credentials (STREAM_API_KEY, STREAM_API_SECRET).
+"""
+
+import asyncio
+import uuid
+
+import pytest
+import pytest_asyncio
+
+from getstream import AsyncStream
+from getstream.models import CallRequest, UserRequest
+from getstream.video import rtc
+from getstream.video.rtc.connection_utils import ConnectionState
+from tests.conftest import skip_on_rate_limit
+
+
+@pytest_asyncio.fixture()
+async def test_user(async_client: AsyncStream):
+    user_id = f"test-user-{uuid.uuid4()}"
+    await async_client.upsert_users(UserRequest(id=user_id))
+    yield user_id
+    try:
+        await async_client.delete_users(
+            user_ids=[user_id], user="hard", conversations="hard", messages="hard"
+        )
+    except Exception:
+        pass
+
+
+@pytest.mark.asyncio
+@pytest.mark.integration
+@skip_on_rate_limit
+async def test_custom_event_round_trip(async_client: AsyncStream, test_user: str):
+    """Send a custom event via REST and verify it arrives on coordinator_ws."""
+    call = async_client.video.call("default", str(uuid.uuid4()))
+    await call.get_or_create(data=CallRequest(created_by_id=test_user))
+
+    async with await rtc.join(call, test_user) as connection:
+        assert connection.connection_state == ConnectionState.JOINED
+
+        ws = connection.coordinator_ws
+        assert ws is not None
+
+        received_event = None
+        event_received = asyncio.Event()
+
+        @ws.on("custom")
+        def on_custom(event):
+            nonlocal received_event
+            received_event = event
+            event_received.set()
+
+        await call.send_call_event(
+            user_id=test_user,
+            custom={"type": "test_event", "payload": "hello from test"},
+        )
+
+        await asyncio.wait_for(event_received.wait(), timeout=10.0)
+
+        assert received_event is not None
+        custom_data = received_event.get("custom", {})
+        assert custom_data.get("type") == "test_event"
+        assert custom_data.get("payload") == "hello from test"