fix(generator): move version checks after __all__ in __init__.py temlate (#18100)

This PR updates the `__init__.py.j2` template to place runtime checks
(`api_core.check_python_version()` and
`api_core.check_dependency_versions()`) at the very end of the file
after `__all__`.

In `gapic-generator 1.38.0`, runtime version and dependency checks were
placed immediately before `__all__`. This created an execution boundary
in the middle of the module:
* When post-processing scripts or handwritten extensions (such as
`SpeechHelpers` in `google-cloud-speech` or `VisionHelpers` in
`google-cloud-vision`) inject helper imports or wrap client classes
prior to `__all__`, linters (Flake8 and Ruff) flag `E402: Module level
import not at top of file`.
* Moving the checks to after `__all__` ensures all module imports remain
contiguous at the top of the file, complying with PEP 8 import ordering
and eliminating the need for `# noqa: E402` annotations in
post-processing.
* Module import semantics remain identical: Python executes the file
top-to-bottom, so environment checks still run immediately upon import
and abort if incompatible versions are detected.

Author: ohmayr

packages/gapic-generator/gapic/templates/%namespace/%name_%version/%sub/__init__.py.j2

@@ -60,9 +60,6 @@ from .types.{{ proto.module_name }} import {{ enum.name }}
 {% endfor %}
 {% endfor %}
 
-api_core.check_python_version("{{package_path}}")
-api_core.check_dependency_versions("{{package_path}}")
-
 {#  Define __all__.
     This requires the full set of imported names, so we iterate over
     them again.
@@ -90,4 +87,8 @@ __all__ = (
     {% endfor -%}
     {% endfilter %}
 )
+
+api_core.check_python_version("{{package_path}}")
+api_core.check_dependency_versions("{{package_path}}")
+
 {% endblock %}

packages/gapic-generator/tests/integration/goldens/asset/google/cloud/asset_v1/__init__.py

@@ -118,9 +118,6 @@
 from .types.assets import TimeWindow
 from .types.assets import VersionedResource
 
-api_core.check_python_version("google.cloud.asset_v1")
-api_core.check_dependency_versions("google.cloud.asset_v1")
-
 __all__ = (
     'AssetServiceAsyncClient',
 'AnalyzeIamPolicyLongrunningMetadata',
@@ -206,3 +203,6 @@
 'UpdateSavedQueryRequest',
 'VersionedResource',
 )
+
+api_core.check_python_version("google.cloud.asset_v1")
+api_core.check_dependency_versions("google.cloud.asset_v1")

packages/gapic-generator/tests/integration/goldens/credentials/google/iam/credentials_v1/__init__.py

@@ -44,9 +44,6 @@
 from .types.common import SignJwtRequest
 from .types.common import SignJwtResponse
 
-api_core.check_python_version("google.iam.credentials_v1")
-api_core.check_dependency_versions("google.iam.credentials_v1")
-
 __all__ = (
     'IAMCredentialsAsyncClient',
 'GenerateAccessTokenRequest',
@@ -59,3 +56,6 @@
 'SignJwtRequest',
 'SignJwtResponse',
 )
+
+api_core.check_python_version("google.iam.credentials_v1")
+api_core.check_dependency_versions("google.iam.credentials_v1")

packages/gapic-generator/tests/integration/goldens/eventarc/google/cloud/eventarc_v1/__init__.py

@@ -116,9 +116,6 @@
 from .types.trigger import Transport
 from .types.trigger import Trigger
 
-api_core.check_python_version("google.cloud.eventarc_v1")
-api_core.check_dependency_versions("google.cloud.eventarc_v1")
-
 __all__ = (
     'EventarcAsyncClient',
 'Channel',
@@ -193,3 +190,6 @@
 'UpdatePipelineRequest',
 'UpdateTriggerRequest',
 )
+
+api_core.check_python_version("google.cloud.eventarc_v1")
+api_core.check_dependency_versions("google.cloud.eventarc_v1")

packages/gapic-generator/tests/integration/goldens/logging/google/cloud/logging_v2/__init__.py

@@ -120,9 +120,6 @@
 from .types.logging_metrics import LogMetric
 from .types.logging_metrics import UpdateLogMetricRequest
 
-api_core.check_python_version("google.cloud.logging_v2")
-api_core.check_dependency_versions("google.cloud.logging_v2")
-
 __all__ = (
     'ConfigServiceV2AsyncClient',
     'LoggingServiceV2AsyncClient',
@@ -207,3 +204,6 @@
 'WriteLogEntriesRequest',
 'WriteLogEntriesResponse',
 )
+
+api_core.check_python_version("google.cloud.logging_v2")
+api_core.check_dependency_versions("google.cloud.logging_v2")

packages/gapic-generator/tests/integration/goldens/logging_internal/google/cloud/logging_v2/__init__.py

@@ -120,9 +120,6 @@
 from .types.logging_metrics import LogMetric
 from .types.logging_metrics import UpdateLogMetricRequest
 
-api_core.check_python_version("google.cloud.logging_v2")
-api_core.check_dependency_versions("google.cloud.logging_v2")
-
 __all__ = (
     'BaseConfigServiceV2AsyncClient',
     'BaseMetricsServiceV2AsyncClient',
@@ -207,3 +204,6 @@
 'WriteLogEntriesRequest',
 'WriteLogEntriesResponse',
 )
+
+api_core.check_python_version("google.cloud.logging_v2")
+api_core.check_dependency_versions("google.cloud.logging_v2")

packages/gapic-generator/tests/integration/goldens/redis/google/cloud/redis_v1/__init__.py

@@ -62,9 +62,6 @@
 from .types.cloud_redis import WeeklyMaintenanceWindow
 from .types.cloud_redis import ZoneMetadata
 
-api_core.check_python_version("google.cloud.redis_v1")
-api_core.check_dependency_versions("google.cloud.redis_v1")
-
 __all__ = (
     'CloudRedisAsyncClient',
 'CloudRedisClient',
@@ -96,3 +93,6 @@
 'WeeklyMaintenanceWindow',
 'ZoneMetadata',
 )
+
+api_core.check_python_version("google.cloud.redis_v1")
+api_core.check_dependency_versions("google.cloud.redis_v1")

packages/gapic-generator/tests/integration/goldens/redis_selective/google/cloud/redis_v1/__init__.py

@@ -55,9 +55,6 @@
 from .types.cloud_redis import WeeklyMaintenanceWindow
 from .types.cloud_redis import ZoneMetadata
 
-api_core.check_python_version("google.cloud.redis_v1")
-api_core.check_dependency_versions("google.cloud.redis_v1")
-
 __all__ = (
     'CloudRedisAsyncClient',
 'CloudRedisClient',
@@ -82,3 +79,6 @@
 'WeeklyMaintenanceWindow',
 'ZoneMetadata',
 )
+
+api_core.check_python_version("google.cloud.redis_v1")
+api_core.check_dependency_versions("google.cloud.redis_v1")

packages/gapic-generator/tests/integration/goldens/storagebatchoperations/google/cloud/storagebatchoperations_v1/__init__.py

@@ -64,9 +64,6 @@
 from .types.storage_batch_operations_types import RewriteObject
 from .types.storage_batch_operations_types import UpdateObjectCustomContext
 
-api_core.check_python_version("google.cloud.storagebatchoperations_v1")
-api_core.check_dependency_versions("google.cloud.storagebatchoperations_v1")
-
 __all__ = (
     'StorageBatchOperationsAsyncClient',
 'BucketList',
@@ -99,3 +96,6 @@
 'StorageBatchOperationsClient',
 'UpdateObjectCustomContext',
 )
+
+api_core.check_python_version("google.cloud.storagebatchoperations_v1")
+api_core.check_dependency_versions("google.cloud.storagebatchoperations_v1")