address Bo comments, move runtime to platform

Author: marcusmotill

src/google/adk/events/event.py

@@ -18,7 +18,8 @@
 from typing import Optional
 import uuid
 
-from google.adk import runtime
+from google.adk.platform import time as platform_time
+from google.adk.platform import uuid as platform_uuid
 from google.genai import types
 from pydantic import alias_generators
 from pydantic import ConfigDict
@@ -71,7 +72,7 @@ class Event(LlmResponse):
   # Do not assign the ID. It will be assigned by the session.
   id: str = ''
   """The unique identifier of the event."""
-  timestamp: float = Field(default_factory=lambda: runtime.get_time())
+  timestamp: float = Field(default_factory=lambda: platform_time.get_time())
   """The timestamp of the event."""
 
   def model_post_init(self, __context):
@@ -126,4 +127,4 @@ def has_trailing_code_execution_result(
 
   @staticmethod
   def new_id():
-    return runtime.new_uuid()
+    return platform_uuid.new_uuid()

src/google/adk/runtime.py src/google/adk/platform/time.pysrc/google/adk/runtime.py renamed to src/google/adk/platform/time.py

@@ -1,4 +1,4 @@
-# Copyright 2025 Google LLC
+# Copyright 2026 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -12,14 +12,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""Runtime module for abstracting system primitives like time and UUIDs."""
+"""Platform module for abstracting system time generation."""
 
 import time
-import uuid
 from typing import Callable
 
-_time_provider: Callable[[], float] = time.time
-_id_provider: Callable[[], str] = lambda: str(uuid.uuid4())
+_default_time_provider: Callable[[], float] = time.time
+_time_provider: Callable[[], float] = _default_time_provider
 
 
 def set_time_provider(provider: Callable[[], float]) -> None:
@@ -33,21 +32,12 @@ def set_time_provider(provider: Callable[[], float]) -> None:
   _time_provider = provider
 
 
-def set_id_provider(provider: Callable[[], str]) -> None:
-  """Sets the provider for generating unique IDs.
-
-  Args:
-    provider: A callable that returns a unique ID string.
-  """
-  global _id_provider
-  _id_provider = provider
+def reset_time_provider() -> None:
+  """Resets the time provider to its default implementation."""
+  global _time_provider
+  _time_provider = _default_time_provider
 
 
 def get_time() -> float:
   """Returns the current time in seconds since the epoch."""
   return _time_provider()
-
-
-def new_uuid() -> str:
-  """Returns a new unique ID."""
-  return _id_provider()

src/google/adk/platform/uuid.py

@@ -0,0 +1,42 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Platform module for abstracting unique ID generation."""
+
+import uuid
+from typing import Callable
+
+_default_id_provider: Callable[[], str] = lambda: str(uuid.uuid4())
+_id_provider: Callable[[], str] = _default_id_provider
+
+
+def set_id_provider(provider: Callable[[], str]) -> None:
+  """Sets the provider for generating unique IDs.
+
+  Args:
+    provider: A callable that returns a unique ID string.
+  """
+  global _id_provider
+  _id_provider = provider
+
+
+def reset_id_provider() -> None:
+  """Resets the ID provider to its default implementation."""
+  global _id_provider
+  _id_provider = _default_id_provider
+
+
+def new_uuid() -> str:
+  """Returns a new unique ID."""
+  return _id_provider()

src/google/adk/sessions/in_memory_session_service.py

@@ -22,7 +22,8 @@
 
 from typing_extensions import override
 
-from google.adk import runtime
+from google.adk.platform import time as platform_time
+from google.adk.platform import uuid as platform_uuid
 from . import _session_util
 from ..errors.already_exists_error import AlreadyExistsError
 from ..events.event import Event
@@ -109,14 +110,14 @@ def _create_session_impl(
     session_id = (
         session_id.strip()
         if session_id and session_id.strip()
-        else runtime.new_uuid()
+        else platform_uuid.new_uuid()
     )
     session = Session(
         app_name=app_name,
         user_id=user_id,
         id=session_id,
         state=session_state or {},
-        last_update_time=runtime.get_time(),
+        last_update_time=platform_time.get_time(),
     )
 
     if app_name not in self.sessions:

tests/unittests/test_runtime.py tests/unittests/platform/test_time.pytests/unittests/test_runtime.py renamed to tests/unittests/platform/test_time.py

@@ -1,4 +1,4 @@
-# Copyright 2025 Google LLC
+# Copyright 2026 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -12,45 +12,29 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""Unit tests for the runtime module."""
+"""Unit tests for the platform time module."""
 
 import time
-import uuid
 import unittest
-from unittest.mock import MagicMock, patch
 
-from google.adk import runtime
+from google.adk.platform import time as platform_time
 
 
-class TestRuntime(unittest.TestCase):
+class TestTime(unittest.TestCase):
 
     def tearDown(self):
-        # Reset providers to default after each test
-        runtime.set_time_provider(time.time)
-        runtime.set_id_provider(lambda: str(uuid.uuid4()))
+        # Reset provider to default after each test
+        platform_time.reset_time_provider()
 
     def test_default_time_provider(self):
         # Verify it returns a float that is close to now
         now = time.time()
-        rt_time = runtime.get_time()
+        rt_time = platform_time.get_time()
         self.assertIsInstance(rt_time, float)
         self.assertAlmostEqual(rt_time, now, delta=1.0)
 
-    def test_default_id_provider(self):
-        # Verify it returns a string uuid
-        uid = runtime.new_uuid()
-        self.assertIsInstance(uid, str)
-        # Should be parseable as uuid
-        uuid.UUID(uid)
-
     def test_custom_time_provider(self):
         # Test override
         mock_time = 123456789.0
-        runtime.set_time_provider(lambda: mock_time)
-        self.assertEqual(runtime.get_time(), mock_time)
-
-    def test_custom_id_provider(self):
-        # Test override
-        mock_id = "test-id-123"
-        runtime.set_id_provider(lambda: mock_id)
-        self.assertEqual(runtime.new_uuid(), mock_id)
+        platform_time.set_time_provider(lambda: mock_time)
+        self.assertEqual(platform_time.get_time(), mock_time)

tests/unittests/platform/test_uuid.py

@@ -0,0 +1,40 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Unit tests for the platform uuid module."""
+
+import uuid
+import unittest
+
+from google.adk.platform import uuid as platform_uuid
+
+
+class TestUUID(unittest.TestCase):
+
+    def tearDown(self):
+        # Reset provider to default after each test
+        platform_uuid.reset_id_provider()
+
+    def test_default_id_provider(self):
+        # Verify it returns a string uuid
+        uid = platform_uuid.new_uuid()
+        self.assertIsInstance(uid, str)
+        # Should be parseable as uuid
+        uuid.UUID(uid)
+
+    def test_custom_id_provider(self):
+        # Test override
+        mock_id = "test-id-123"
+        platform_uuid.set_id_provider(lambda: mock_id)
+        self.assertEqual(platform_uuid.new_uuid(), mock_id)