chore: Defer import of live, Client and _transformers in google.genai

Co-authored-by: Liang Wu <wuliang@google.com>
PiperOrigin-RevId: 831444358

Author: wuliang229

src/google/adk/flows/llm_flows/instructions.py

@@ -19,7 +19,6 @@
 from typing import AsyncGenerator
 from typing import TYPE_CHECKING
 
-from google.genai import _transformers
 from typing_extensions import override
 
 from ...agents.readonly_context import ReadonlyContext
@@ -85,6 +84,8 @@ async def run_async(
 
     # Handle static_instruction - add via append_instructions
     if agent.static_instruction:
+      from google.genai import _transformers
+
       # Convert ContentUnion to Content using genai transformer
       static_content = _transformers.t_content(agent.static_instruction)
       llm_request.append_instructions(static_content)

src/google/adk/models/apigee_llm.py

@@ -18,21 +18,22 @@
 from functools import cached_property
 import logging
 import os
-import re
 from typing import Optional
 from typing import TYPE_CHECKING
 
 from google.adk import version as adk_version
-from google.genai import Client
 from google.genai import types
 from typing_extensions import override
 
 from ..utils.env_utils import is_env_enabled
 from .google_llm import Gemini
 
 if TYPE_CHECKING:
+  from google.genai import Client
+
   from .llm_request import LlmRequest
 
+
 logger = logging.getLogger('google_adk.' + __name__)
 
 _APIGEE_PROXY_URL_ENV_VARIABLE_NAME = 'APIGEE_PROXY_URL'
@@ -137,6 +138,7 @@ def api_client(self) -> Client:
     Returns:
       The api client.
     """
+    from google.genai import Client
 
     kwargs_for_http_options = {}
     if self._api_version:

src/google/adk/models/gemini_context_cache_manager.py

@@ -21,8 +21,8 @@
 import logging
 import time
 from typing import Optional
+from typing import TYPE_CHECKING
 
-from google.genai import Client
 from google.genai import types
 
 from ..utils.feature_decorator import experimental
@@ -32,6 +32,9 @@
 
 logger = logging.getLogger("google_adk." + __name__)
 
+if TYPE_CHECKING:
+  from google.genai import Client
+
 
 @experimental
 class GeminiContextCacheManager:

src/google/adk/models/gemini_llm_connection.py

@@ -18,7 +18,6 @@
 from typing import AsyncGenerator
 from typing import Union
 
-from google.genai import live
 from google.genai import types
 
 from ..utils.context_utils import Aclosing
@@ -28,6 +27,10 @@
 logger = logging.getLogger('google_adk.' + __name__)
 
 RealtimeInput = Union[types.Blob, types.ActivityStart, types.ActivityEnd]
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+  from google.genai import live
 
 
 class GeminiLlmConnection(BaseLlmConnection):

src/google/adk/models/google_llm.py

@@ -27,7 +27,6 @@
 from typing import TYPE_CHECKING
 from typing import Union
 
-from google.genai import Client
 from google.genai import types
 from typing_extensions import override
 
@@ -41,6 +40,8 @@
 from .llm_response import LlmResponse
 
 if TYPE_CHECKING:
+  from google.genai import Client
+
   from .llm_request import LlmRequest
 
 logger = logging.getLogger('google_adk.' + __name__)
@@ -200,6 +201,8 @@ def api_client(self) -> Client:
     Returns:
       The api client.
     """
+    from google.genai import Client
+
     return Client(
         http_options=types.HttpOptions(
             headers=self._tracking_headers,
@@ -239,6 +242,8 @@ def _live_api_version(self) -> str:
 
   @cached_property
   def _live_api_client(self) -> Client:
+    from google.genai import Client
+
     return Client(
         http_options=types.HttpOptions(
             headers=self._tracking_headers, api_version=self._live_api_version

tests/unittests/models/test_apigee_llm.py

@@ -46,7 +46,7 @@ def llm_request():
 
 
 @pytest.mark.asyncio
-@mock.patch('google.adk.models.apigee_llm.Client')
+@mock.patch('google.genai.Client')
 async def test_generate_content_async_non_streaming(
     mock_client_constructor, llm_request
 ):
@@ -96,7 +96,7 @@ async def test_generate_content_async_non_streaming(
 
 
 @pytest.mark.asyncio
-@mock.patch('google.adk.models.apigee_llm.Client')
+@mock.patch('google.genai.Client')
 async def test_generate_content_async_streaming(
     mock_client_constructor, llm_request
 ):
@@ -167,7 +167,7 @@ async def mock_stream_generator():
 
 
 @pytest.mark.asyncio
-@mock.patch('google.adk.models.apigee_llm.Client')
+@mock.patch('google.genai.Client')
 async def test_generate_content_async_with_custom_headers(
     mock_client_constructor, llm_request
 ):
@@ -207,7 +207,7 @@ async def test_generate_content_async_with_custom_headers(
 
 
 @pytest.mark.asyncio
-@mock.patch('google.adk.models.apigee_llm.Client')
+@mock.patch('google.genai.Client')
 async def test_vertex_model_path_parsing(mock_client_constructor):
   """Tests that Vertex AI model paths are parsed correctly."""
   apigee_llm = ApigeeLlm(model=APIGEE_VERTEX_MODEL_ID, proxy_url=PROXY_URL)
@@ -249,7 +249,7 @@ async def test_vertex_model_path_parsing(mock_client_constructor):
 
 
 @pytest.mark.asyncio
-@mock.patch('google.adk.models.apigee_llm.Client')
+@mock.patch('google.genai.Client')
 async def test_proxy_url_from_env_variable(mock_client_constructor):
   """Tests that proxy_url is read from environment variable."""
   with mock.patch.dict(
@@ -381,7 +381,7 @@ def test_vertex_model_missing_project_or_location_raises_error(
         ),
     ],
 )
-@mock.patch('google.adk.models.apigee_llm.Client')
+@mock.patch('google.genai.Client')
 async def test_model_string_parsing_and_client_initialization(
     mock_client_constructor,
     model_string,