Fix bundled Gemini Live transcription ordering

src/pipecat/services/google/gemini_live/llm.py

@@ -1361,9 +1361,9 @@ class GeminiLiveLLMService(LLMService):
                         self._check_and_reset_failure_counter()
 
                         # server_content fields are NOT mutually exclusive —
-                        # Gemini 3.x can bundle e.g. model_turn and
-                        # output_transcription on the same message — so check
-                        # each field independently.
+                        # Gemini 3.x can bundle multiple content fields and
+                        # turn_complete on the same message, so process the
+                        # content-bearing fields before closing the turn.
                         sc = message.server_content
                         if sc and sc.interrupted:
                             # NOTE: while the service triggers interruptions in
@@ -1380,18 +1380,25 @@ class GeminiLiveLLMService(LLMService):
                             await self.broadcast_interruption()
                         if sc and sc.model_turn:
                             await self._handle_msg_model_turn(message)
+                        if sc and sc.input_transcription:
+                            await self._handle_msg_input_transcription(message)
+                        if sc and sc.output_transcription:
+                            await self._handle_msg_output_transcription(message)
+                        if (
+                            sc
+                            and sc.grounding_metadata
+                            and not sc.model_turn
+                            and not sc.output_transcription
+                        ):
+                            # model_turn/output_transcription already defer
+                            # bundled grounding metadata to turn_complete.
+                            await self._handle_msg_grounding_metadata(message)
                         if sc and sc.turn_complete:
                             if not message.usage_metadata:
                                 logger.warning("Received turn_complete without usage_metadata")
                             await self._handle_msg_turn_complete(message)
                             if message.usage_metadata:
                                 await self._handle_msg_usage_metadata(message)
-                        if sc and sc.input_transcription:
-                            await self._handle_msg_input_transcription(message)
-                        if sc and sc.output_transcription:
-                            await self._handle_msg_output_transcription(message)
-                        if sc and sc.grounding_metadata:
-                            await self._handle_msg_grounding_metadata(message)
                         if message.tool_call:
                             await self._handle_msg_tool_call(message)
                         if message.session_resumption_update:

tests/test_google_gemini_live_llm.py

@@ -0,0 +1,190 @@
+#
+# Copyright (c) 2024-2026, Daily
+#
+# SPDX-License-Identifier: BSD 2-Clause License
+#
+
+"""Unit tests for Gemini Live message dispatch ordering."""
+
+import warnings
+from types import SimpleNamespace
+from unittest.mock import AsyncMock, patch
+
+import pytest
+
+try:
+    from pipecat.services.google.gemini_live.llm import GeminiLiveLLMService
+
+    google_available = True
+except Exception:
+    google_available = False
+
+
+class _SingleMessageTurn:
+    def __init__(self, message):
+        self._message = message
+        self._sent = False
+
+    def __aiter__(self):
+        return self
+
+    async def __anext__(self):
+        if self._sent:
+            raise StopAsyncIteration
+        self._sent = True
+        return self._message
+
+
+class _SingleMessageSession:
+    def __init__(self, message):
+        self._message = message
+        self._received = False
+
+    def receive(self):
+        if self._received:
+            raise RuntimeError("stop test session")
+        self._received = True
+        return _SingleMessageTurn(self._message)
+
+
+class _MockConnect:
+    def __init__(self, session):
+        self._session = session
+
+    async def __aenter__(self):
+        return self._session
+
+    async def __aexit__(self, exc_type, exc_val, exc_tb):
+        return False
+
+
+def _make_service():
+    with patch.object(GeminiLiveLLMService, "create_client"):
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            return GeminiLiveLLMService(api_key="test-key", model="test-model")
+
+
+def _make_message(
+    *,
+    model_turn=None,
+    turn_complete=False,
+    output_transcription=None,
+    grounding_metadata=None,
+    usage_metadata=None,
+):
+    server_content = SimpleNamespace(
+        interrupted=False,
+        model_turn=model_turn,
+        turn_complete=turn_complete,
+        input_transcription=None,
+        output_transcription=output_transcription,
+        grounding_metadata=grounding_metadata,
+    )
+    return SimpleNamespace(
+        server_content=server_content,
+        usage_metadata=usage_metadata,
+        tool_call=None,
+        session_resumption_update=None,
+    )
+
+
+async def _run_single_message(service, message):
+    session = _SingleMessageSession(message)
+    service._client = SimpleNamespace(
+        aio=SimpleNamespace(live=SimpleNamespace(connect=lambda **kwargs: _MockConnect(session)))
+    )
+    service._disconnecting = True
+    await service._connection_task_handler(config=SimpleNamespace())
+
+
+def _async_recorder(order, name):
+    async def _record(message):
+        order.append(name)
+
+    return _record
+
+
+@pytest.mark.asyncio
+@pytest.mark.skipif(not google_available, reason="Google dependencies not installed")
+async def test_output_transcription_is_processed_before_turn_complete():
+    service = _make_service()
+    order = []
+
+    service._handle_msg_model_turn = AsyncMock(side_effect=_async_recorder(order, "model_turn"))
+    service._handle_msg_output_transcription = AsyncMock(
+        side_effect=_async_recorder(order, "output_transcription")
+    )
+    service._handle_msg_turn_complete = AsyncMock(
+        side_effect=_async_recorder(order, "turn_complete")
+    )
+    service._handle_msg_usage_metadata = AsyncMock(
+        side_effect=_async_recorder(order, "usage_metadata")
+    )
+
+    message = _make_message(
+        model_turn=object(),
+        output_transcription=object(),
+        turn_complete=True,
+        usage_metadata=object(),
+    )
+    await _run_single_message(service, message)
+
+    assert order == ["model_turn", "output_transcription", "turn_complete", "usage_metadata"]
+
+
+@pytest.mark.asyncio
+@pytest.mark.skipif(not google_available, reason="Google dependencies not installed")
+async def test_bundled_grounding_metadata_is_not_emitted_immediately():
+    service = _make_service()
+    order = []
+
+    service._handle_msg_output_transcription = AsyncMock(
+        side_effect=_async_recorder(order, "output_transcription")
+    )
+    service._handle_msg_grounding_metadata = AsyncMock(
+        side_effect=_async_recorder(order, "grounding_metadata")
+    )
+    service._handle_msg_turn_complete = AsyncMock(
+        side_effect=_async_recorder(order, "turn_complete")
+    )
+    service._handle_msg_usage_metadata = AsyncMock(
+        side_effect=_async_recorder(order, "usage_metadata")
+    )
+
+    message = _make_message(
+        output_transcription=object(),
+        grounding_metadata=object(),
+        turn_complete=True,
+        usage_metadata=object(),
+    )
+    await _run_single_message(service, message)
+
+    assert order == ["output_transcription", "turn_complete", "usage_metadata"]
+    service._handle_msg_grounding_metadata.assert_not_called()
+
+
+@pytest.mark.asyncio
+@pytest.mark.skipif(not google_available, reason="Google dependencies not installed")
+async def test_standalone_grounding_metadata_is_still_emitted():
+    service = _make_service()
+    order = []
+
+    service._handle_msg_grounding_metadata = AsyncMock(
+        side_effect=_async_recorder(order, "grounding_metadata")
+    )
+    service._handle_msg_turn_complete = AsyncMock(
+        side_effect=_async_recorder(order, "turn_complete")
+    )
+    service._handle_msg_usage_metadata = AsyncMock(
+        side_effect=_async_recorder(order, "usage_metadata")
+    )
+
+    message = _make_message(
+        grounding_metadata=object(),
+        turn_complete=True,
+        usage_metadata=object(),
+    )
+    await _run_single_message(service, message)
+
+    assert order == ["grounding_metadata", "turn_complete", "usage_metadata"]