chore: add showcase e2e tests for async rest

.github/workflows/tests.yaml

@@ -55,8 +55,9 @@ jobs:
     strategy:
       # Run showcase tests on the lowest and highest supported runtimes
       matrix:
+        # TODO(https://github.com/googleapis/gapic-generator-python/issues/2121) Remove `showcase_w_rest_async` target when async rest is GA.
         python: ["3.7", "3.12"]
-        target: [showcase, showcase_alternative_templates]
+        target: [showcase, showcase_alternative_templates, showcase_w_rest_async]
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4

gapic/ads-templates/%namespace/%name/%version/%sub/services/%service/_shared_macros.j2

@@ -57,6 +57,7 @@ The `try/except` below can be removed once the minimum version of
 try:
     from google.api_core import version_header
     HAS_GOOGLE_API_CORE_VERSION_HEADER = True  # pragma: NO COVER
+{# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
 except ImportError:  # pragma: NO COVER
     HAS_GOOGLE_API_CORE_VERSION_HEADER = False
 {% endif %}{# service_version #}

gapic/templates/%namespace/%name_%version/%sub/services/%service/client.py.j2

@@ -69,10 +69,18 @@ from .transports.rest import {{ service.name }}RestTransport
 try:
     from .transports.rest_asyncio import Async{{ service.name }}RestTransport
     HAS_GOOGLE_AUTH_AIO = True
+{# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
 except ImportError as e: # pragma: NO COVER
     HAS_GOOGLE_AUTH_AIO = False
     GOOGLE_AUTH_AIO_EXCEPTION = e
 
+try:
+    import aiohttp  # type: ignore
+    HAS_AIOHTTP_INSTALLED = True
+{# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
+except ImportError as e: # pragma: NO COVER
+    HAS_AIOHTTP_INSTALLED = False
+
 {% endif %}{# if rest_async_io_enabled #}
 {% endif %}
 
@@ -93,7 +101,7 @@ class {{ service.client_name }}Meta(type):
     _transport_registry["rest"] = {{ service.name }}RestTransport
     {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2121): Remove this condition when async rest is GA. #}
     {% if rest_async_io_enabled %}
-    if HAS_GOOGLE_AUTH_AIO:  # pragma: NO COVER
+    if HAS_GOOGLE_AUTH_AIO and HAS_AIOHTTP_INSTALLED:  # pragma: NO COVER
         _transport_registry["rest_asyncio"] = Async{{ service.name }}RestTransport
     {% endif %}{# if rest_async_io_enabled #}
     {% endif %}
@@ -113,8 +121,12 @@ class {{ service.client_name }}Meta(type):
         # If a specific transport is requested, return that one.
         {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2121): Remove this condition when async rest is GA. #}
         {% if rest_async_io_enabled %}
+        {# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
         if label == "rest_asyncio" and not HAS_GOOGLE_AUTH_AIO:  # pragma: NO COVER
             raise GOOGLE_AUTH_AIO_EXCEPTION
+        {# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
+        elif label == "rest_asyncio" and not HAS_AIOHTTP_INSTALLED:  # pragma: NO COVER
+            raise ImportError("async rest transport requires aiohttp external package.")
         {% endif %}
         if label:
             return cls._transport_registry[label]

gapic/templates/%namespace/%name_%version/%sub/services/%service/transports/__init__.py.j2

@@ -1,9 +1,11 @@
+{# TODO(https://github.com/googleapis/gapic-generator-python/issues/2121): Remove the following variable (and the condition later in this file) for async rest transport once support for it is GA. #}
+{% set rest_async_io_enabled = api.all_library_settings[api.naming.proto_package].python_settings.experimental_features.rest_async_io_enabled %}
 {% extends '_base.py.j2' %}
 
 {% block content %}
 
 from collections import OrderedDict
-from typing import Dict, Type
+from typing import Dict, Type{% if rest_async_io_enabled %}, Tuple{% endif +%}
 
 from .base import {{ service.name }}Transport
 {% if 'grpc' in opts.transport %}
@@ -13,6 +15,16 @@ from .grpc_asyncio import {{ service.name }}GrpcAsyncIOTransport
 {% if 'rest' in opts.transport %}
 from .rest import {{ service.name }}RestTransport
 from .rest import {{ service.name }}RestInterceptor
+{% if rest_async_io_enabled %}
+ASYNC_REST_CLASSES: Tuple[str, ...]
+try:
+    from .rest_asyncio import Async{{ service.name }}RestTransport
+    ASYNC_REST_CLASSES = ('Async{{ service.name }}RestTransport',)
+    HAS_REST_ASYNC = True
+except ImportError:  # pragma: NO COVER
+    ASYNC_REST_CLASSES = ()
+    HAS_REST_ASYNC = False
+{% endif %}{# if rest_async_io_enabled #}
 {% endif %}
 
 
@@ -25,6 +37,10 @@ _transport_registry['grpc_asyncio'] = {{ service.name }}GrpcAsyncIOTransport
 {% endif %}
 {% if 'rest' in opts.transport %}
 _transport_registry['rest'] = {{ service.name }}RestTransport
+{% if rest_async_io_enabled %}
+if HAS_REST_ASYNC:  # pragma: NO COVER
+    _transport_registry['rest_asyncio'] = Async{{ service.name }}RestTransport
+{% endif %}{# if rest_async_io_enabled #}
 {% endif %}
 
 __all__ = (
@@ -37,5 +53,5 @@ __all__ = (
     '{{ service.name }}RestTransport',
     '{{ service.name }}RestInterceptor',
     {% endif %}
-)
+){% if 'rest' in opts.transport and rest_async_io_enabled%} + ASYNC_REST_CLASSES{%endif%}
 {% endblock %}

gapic/templates/%namespace/%name_%version/%sub/services/%service/transports/rest_asyncio.py.j2

@@ -5,8 +5,16 @@
 
 {% block content %}
 
+try:
+    import aiohttp # type: ignore
+{# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
+except ImportError as e:  # pragma: NO COVER
+    raise ImportError("async rest transport requires aiohttp external package.") from e
+
+import google.auth
 try:
     from google.auth.aio.transport.sessions import AsyncAuthorizedSession # type: ignore
+{# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
 except ImportError as e:  # pragma: NO COVER
     {# TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged. #}
     raise ImportError("async rest transport requires google.auth >= 2.x.x") from e
@@ -35,11 +43,10 @@ try:
 except AttributeError:  # pragma: NO COVER
     OptionalRetry = Union[retries.AsyncRetry, object, None]  # type: ignore
 
-{# TODO (https://github.com/googleapis/gapic-generator-python/issues/2128): Update `rest_version` to include the transport dependency version. #}
 DEFAULT_CLIENT_INFO = gapic_v1.client_info.ClientInfo(
     gapic_version=BASE_DEFAULT_CLIENT_INFO.gapic_version,
     grpc_version=None,
-    rest_version=None,
+    rest_version=google.auth.__version__
 )
 
 {# TODO: Add an `_interceptor` property once implemented #}

gapic/templates/tests/unit/gapic/%name_%version/%sub/test_%service.py.j2

@@ -30,6 +30,14 @@ from google.api_core import api_core_version
 from proto.marshal.rules.dates import DurationRule, TimestampRule
 from proto.marshal.rules import wrappers
 {% if 'rest' in opts.transport %}
+{% if rest_async_io_enabled %}
+try:
+    import aiohttp  # type: ignore
+    HAS_AIOHTTP_INSTALLED = True
+{# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
+except ImportError: # pragma: NO COVER
+    HAS_AIOHTTP_INSTALLED = False
+{% endif %}{# if rest_async_io_enabled #}
 from requests import Response
 from requests import Request, PreparedRequest
 from requests.sessions import Session
@@ -43,6 +51,7 @@ try:
     from google.auth.aio.transport.sessions import AsyncAuthorizedSession
     {% endif %}
     HAS_GOOGLE_AUTH_AIO = True
+{# NOTE: `pragma: NO COVER` is needed since the coverage for presubmits isn't combined. #}
 except ImportError: # pragma: NO COVER
     HAS_GOOGLE_AUTH_AIO = False
 

gapic/templates/tests/unit/gapic/%name_%version/%sub/test_macros.j2

@@ -1861,6 +1861,8 @@ def test_transport_kind_{{ transport_name }}():
     if not HAS_GOOGLE_AUTH_AIO:
         {# TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged. #}
         pytest.skip("google-auth > 2.x.x is required for async rest transport.")
+    elif not HAS_AIOHTTP_INSTALLED:
+        pytest.skip("aiohttp is required for async rest transport.")
     {% endif %}
     transport = {{ get_client(service, is_async) }}.get_transport_class("{{ transport_name }}")(
         credentials={{get_credentials(is_async)}}
@@ -1884,6 +1886,8 @@ def test_transport_kind_{{ transport_name }}():
     if not HAS_GOOGLE_AUTH_AIO:
         {# TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged. #}
         pytest.skip("google-auth > 2.x.x is required for async rest transport.")
+    elif not HAS_AIOHTTP_INSTALLED:
+        pytest.skip("aiohttp is required for async rest transport.")
     {% endif %}
     client = {{ get_client(service, is_async) }}(
         credentials={{get_credentials(is_async)}},
@@ -1902,6 +1906,8 @@ def test_unsupported_parameter_rest_asyncio():
     if not HAS_GOOGLE_AUTH_AIO:
         {# TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged. #}
         pytest.skip("google-auth > 2.x.x is required for async rest transport.")
+    elif not HAS_AIOHTTP_INSTALLED:
+        pytest.skip("aiohttp is required for async rest transport.")
     options = client_options.ClientOptions(quota_project_id="octopus")
     {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2137): Remove `type: ignore` once we add a version check for google-api-core. #}
     with pytest.raises(core_exceptions.AsyncRestUnsupportedParameterError, match="google.api_core.client_options.ClientOptions.quota_project_id") as exc:  # type: ignore
@@ -1987,6 +1993,8 @@ def test_unsupported_parameter_rest_asyncio():
     if not HAS_GOOGLE_AUTH_AIO:
         {# TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged. #}
         pytest.skip("google-auth > 2.x.x is required for async rest transport.")
+    elif not HAS_AIOHTTP_INSTALLED:
+        pytest.skip("aiohttp is required for async rest transport.")
     {% endif %}
 
     client = {{ get_client(service, is_async) }}(
@@ -2015,6 +2023,8 @@ def test_initialize_client_w_{{transport_name}}():
     if not HAS_GOOGLE_AUTH_AIO:
         {# TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged. #}
         pytest.skip("google-auth > 2.x.x is required for async rest transport.")
+    elif not HAS_AIOHTTP_INSTALLED:
+        pytest.skip("aiohttp is required for async rest transport.")
     {% endif %}
     client = {{ get_client(service, is_async) }}(
         credentials={{get_credentials(is_async)}},
@@ -2044,7 +2054,8 @@ def test_initialize_client_w_{{transport_name}}():
     if not HAS_GOOGLE_AUTH_AIO:
         {# TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged. #}
         pytest.skip("google-auth > 2.x.x is required for async rest transport.")
-
+    elif not HAS_AIOHTTP_INSTALLED:
+        pytest.skip("aiohttp is required for async rest transport.")
     {% endif %}
     client = {{ get_client(service, is_async) }}(
         credentials={{get_credentials(is_async)}},
@@ -2110,6 +2121,8 @@ def test_initialize_client_w_{{transport_name}}():
     if not HAS_GOOGLE_AUTH_AIO:
         {# TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged. #}
         pytest.skip("google-auth > 2.x.x is required for async rest transport.")
+    elif not HAS_AIOHTTP_INSTALLED:
+        pytest.skip("aiohttp is required for async rest transport.")
 
     {% endif %}
     client = {{ get_client(service, is_async) }}(

noxfile.py

@@ -341,6 +341,39 @@ def showcase(
             env=env,
         )
 
+@nox.session(python=ALL_PYTHON)
+def showcase_w_rest_async(
+    session,
+    templates="DEFAULT",
+    other_opts: typing.Iterable[str] = (),
+    env: typing.Optional[typing.Dict[str, str]] = {},
+):
+    """Run the Showcase test suite."""
+
+    with showcase_library(session, templates=templates, other_opts=other_opts, rest_async_io_enabled=True):
+        session.install("aiohttp")
+        session.install("pytest", "pytest-asyncio")
+        test_directory = Path("tests", "system")
+        ignore_file = env.get("IGNORE_FILE")
+        pytest_command = [
+            "py.test",
+            "--quiet",
+            *(session.posargs or [str(test_directory)]),
+        ]
+        if ignore_file:
+            ignore_path = test_directory / ignore_file
+            pytest_command.extend(["--ignore", str(ignore_path)])
+
+        # Note: google-api-core and google-auth are re-installed here to override the version installed in constraints.
+        # TODO(https://github.com/googleapis/python-api-core/pull/694): Update the version of google-api-core once the linked PR is merged.
+        session.install('--no-cache-dir', '--force-reinstall', "google-api-core[grpc]@git+https://github.com/googleapis/python-api-core.git@7dea20d73878eca93b61bb82ae6ddf335fb3a8ca")
+        # TODO(https://github.com/googleapis/google-auth-library-python/pull/1577): Update the version of google-auth once the linked PR is merged.
+        session.install('--no-cache-dir', '--force-reinstall', "google-auth@git+https://github.com/googleapis/google-auth-library-python.git")
+        session.run(
+            *pytest_command,
+            env=env,
+        )
+
 
 @nox.session(python=NEWEST_PYTHON)
 def showcase_mtls(

tests/integration/goldens/redis/google/cloud/redis_v1/services/cloud_redis/client.py

@@ -56,6 +56,12 @@
     HAS_GOOGLE_AUTH_AIO = False
     GOOGLE_AUTH_AIO_EXCEPTION = e
 
+try:
+    import aiohttp  # type: ignore
+    HAS_AIOHTTP_INSTALLED = True
+except ImportError as e: # pragma: NO COVER
+    HAS_AIOHTTP_INSTALLED = False
+
 
 class CloudRedisClientMeta(type):
     """Metaclass for the CloudRedis client.
@@ -68,7 +74,7 @@ class CloudRedisClientMeta(type):
     _transport_registry["grpc"] = CloudRedisGrpcTransport
     _transport_registry["grpc_asyncio"] = CloudRedisGrpcAsyncIOTransport
     _transport_registry["rest"] = CloudRedisRestTransport
-    if HAS_GOOGLE_AUTH_AIO:  # pragma: NO COVER
+    if HAS_GOOGLE_AUTH_AIO and HAS_AIOHTTP_INSTALLED:  # pragma: NO COVER
         _transport_registry["rest_asyncio"] = AsyncCloudRedisRestTransport
 
     def get_transport_class(cls,
@@ -86,6 +92,8 @@ def get_transport_class(cls,
         # If a specific transport is requested, return that one.
         if label == "rest_asyncio" and not HAS_GOOGLE_AUTH_AIO:  # pragma: NO COVER
             raise GOOGLE_AUTH_AIO_EXCEPTION
+        elif label == "rest_asyncio" and not HAS_AIOHTTP_INSTALLED:  # pragma: NO COVER
+            raise ImportError("async rest transport requires aiohttp external package.")
         if label:
             return cls._transport_registry[label]
 

tests/integration/goldens/redis/google/cloud/redis_v1/services/cloud_redis/transports/__init__.py

@@ -14,25 +14,35 @@
 # limitations under the License.
 #
 from collections import OrderedDict
-from typing import Dict, Type
+from typing import Dict, Type, Tuple
 
 from .base import CloudRedisTransport
 from .grpc import CloudRedisGrpcTransport
 from .grpc_asyncio import CloudRedisGrpcAsyncIOTransport
 from .rest import CloudRedisRestTransport
 from .rest import CloudRedisRestInterceptor
+ASYNC_REST_CLASSES: Tuple[str, ...]
+try:
+    from .rest_asyncio import AsyncCloudRedisRestTransport
+    ASYNC_REST_CLASSES = ('AsyncCloudRedisRestTransport',)
+    HAS_REST_ASYNC = True
+except ImportError:  # pragma: NO COVER
+    ASYNC_REST_CLASSES = ()
+    HAS_REST_ASYNC = False
 
 
 # Compile a registry of transports.
 _transport_registry = OrderedDict()  # type: Dict[str, Type[CloudRedisTransport]]
 _transport_registry['grpc'] = CloudRedisGrpcTransport
 _transport_registry['grpc_asyncio'] = CloudRedisGrpcAsyncIOTransport
 _transport_registry['rest'] = CloudRedisRestTransport
+if HAS_REST_ASYNC:  # pragma: NO COVER
+    _transport_registry['rest_asyncio'] = AsyncCloudRedisRestTransport
 
 __all__ = (
     'CloudRedisTransport',
     'CloudRedisGrpcTransport',
     'CloudRedisGrpcAsyncIOTransport',
     'CloudRedisRestTransport',
     'CloudRedisRestInterceptor',
-)
+) + ASYNC_REST_CLASSES

tests/integration/goldens/redis/google/cloud/redis_v1/services/cloud_redis/transports/rest_asyncio.py

@@ -13,6 +13,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
+try:
+    import aiohttp # type: ignore
+except ImportError as e:  # pragma: NO COVER
+    raise ImportError("async rest transport requires aiohttp external package.") from e
+
+import google.auth
 try:
     from google.auth.aio.transport.sessions import AsyncAuthorizedSession # type: ignore
 except ImportError as e:  # pragma: NO COVER
@@ -48,7 +54,7 @@
 DEFAULT_CLIENT_INFO = gapic_v1.client_info.ClientInfo(
     gapic_version=BASE_DEFAULT_CLIENT_INFO.gapic_version,
     grpc_version=None,
-    rest_version=None,
+    rest_version=google.auth.__version__
 )
 
 @dataclasses.dataclass