fix(cli): preserve Docker dependency cache

src/google/adk/cli/cli_deploy.py

@@ -175,6 +175,18 @@ def _ensure_agent_engine_dependency(requirements_txt_path: str) -> None:
     f.write(f'google-adk[a2a]=={__version__}\n')
 
 
+def _get_agent_requirements_copy(
+    app_name: str, requirements_txt_path: str
+) -> str:
+  """Returns the Dockerfile step that copies an agent's requirements file."""
+  if not os.path.exists(requirements_txt_path):
+    return ''
+  return (
+      f'COPY --chown=myuser:myuser "agents/{app_name}/requirements.txt" '
+      f'"/app/agents/{app_name}/requirements.txt"'
+  )
+
+
 _DOCKERFILE_TEMPLATE: Final[str] = """
 FROM python:3.11-slim
 WORKDIR /app
@@ -200,17 +212,18 @@ def _ensure_agent_engine_dependency(requirements_txt_path: str) -> None:
 RUN python -c "import os, glob, google.adk.cli as cli; d = os.path.dirname(cli.__file__); [os.remove(f) for f in glob.glob(os.path.join(d, 'dev_server*'))]; [os.remove(f) for f in glob.glob(os.path.join(d, '__pycache__', 'dev_server*'))]" || true
 # Install ADK - End
 
+# Install Agent Deps - Start
+{agent_requirements_copy}
+{install_agent_deps}
+# Install Agent Deps - End
+
 # Copy agent - Start
 
 # Set permission
 COPY --chown=myuser:myuser "agents/{app_name}/" "/app/agents/{app_name}/"
 {extra_packages_copy}
 # Copy agent - End
 
-# Install Agent Deps - Start
-{install_agent_deps}
-# Install Agent Deps - End
-
 EXPOSE {port}
 
 CMD adk {command} --port={port} {host_option} {service_option} {trace_to_cloud_option} {otel_to_cloud_option} {allow_origins_option} {a2a_option} {trigger_sources_option} {gemini_enterprise_option}{express_mode_option} "/app/agents"
@@ -855,6 +868,9 @@ def to_cloud_run(
         app_name=app_name,
         port=port,
         command='api_server --with_ui' if with_ui else 'api_server',
+        agent_requirements_copy=_get_agent_requirements_copy(
+            app_name, requirements_txt_path
+        ),
         install_agent_deps=install_agent_deps,
         service_option=_get_service_option_by_adk_version(
             adk_version,
@@ -1380,6 +1396,9 @@ def create_dockerfile_for_agent_engine(resource_name: str) -> None:
           app_name=app_name,
           port=8080,
           command='api_server',
+          agent_requirements_copy=_get_agent_requirements_copy(
+              app_name, requirements_txt_path
+          ),
           install_agent_deps=install_agent_deps,
           service_option=_get_service_option_by_adk_version(
               adk_version,
@@ -1560,6 +1579,9 @@ def to_gke(
         app_name=app_name,
         port=port,
         command='api_server --with_ui' if with_ui else 'api_server',
+        agent_requirements_copy=_get_agent_requirements_copy(
+            app_name, requirements_txt_path
+        ),
         install_agent_deps=install_agent_deps,
         service_option=_get_service_option_by_adk_version(
             adk_version,

tests/unittests/cli/utils/test_cli_deploy_to_cloud_run.py

@@ -158,11 +158,29 @@ def test_to_cloud_run_happy_path(
 
   # Check agent dependencies installation based on include_requirements
   if include_requirements:
+    requirements_copy = (
+        'COPY --chown=myuser:myuser "agents/agent/requirements.txt" '
+        '"/app/agents/agent/requirements.txt"'
+    )
+    agent_copy = (
+        'COPY --chown=myuser:myuser "agents/agent/" "/app/agents/agent/"'
+    )
+    assert requirements_copy in dockerfile_content
     assert (
         'RUN pip install -r "/app/agents/agent/requirements.txt"'
         in dockerfile_content
     )
+    assert (
+        dockerfile_content.index(requirements_copy)
+        < dockerfile_content.index(
+            'RUN pip install -r "/app/agents/agent/requirements.txt"'
+        )
+        < dockerfile_content.index(agent_copy)
+    )
   else:
+    assert 'COPY --chown=myuser:myuser "agents/agent/requirements.txt"' not in (
+        dockerfile_content
+    )
     assert "# No requirements.txt found." in dockerfile_content
 
   assert (