feat: implement a basic async rest method

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

@@ -181,7 +181,8 @@ def _get_http_options():
         payload = json.loads(content.decode('utf-8'))
         request_url = "{host}{uri}".format(host=self._host, uri=transcoded_request['uri'])
         method = transcoded_request['method']
-        raise core_exceptions.format_http_response_error(response, method, request_url, payload)
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2137): Remove `type:  ignore` once version check is added for google-api-core. #}
+        raise core_exceptions.format_http_response_error(response, method, request_url, payload)  # type: ignore
         {% else %}
         raise core_exceptions.from_http_response(response)
         {% endif %}{# is_async #}

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

@@ -16,7 +16,11 @@ from google.auth.aio import credentials as ga_credentials_async  # type: ignore
 from google.api_core import exceptions as core_exceptions
 from google.api_core import gapic_v1
 from google.api_core import retry_async as retries
+from google.api_core import rest_helpers
 
+from google.protobuf import json_format
+
+import json  # type: ignore
 import dataclasses
 from typing import Any, Callable, Tuple, Optional, Sequence, Union
 
@@ -109,16 +113,73 @@ class Async{{service.name}}RestTransport(_Base{{ service.name }}RestTransport):
         def __hash__(self):
             return hash("Async{{service.name}}RestTransport.{{method.name}}")
 
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2168): Implement server streaming method. #}
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2169): Implement client streaming method. #}
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2170): Implement long running operation method. #}
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2171): Implement pager method. #}
+        {% if method.http_options and not method.client_streaming and not method.server_streaming and not method.lro and not method.extended_lro and not method.paged_result_field %}
+        {% set body_spec = method.http_options[0].body %}
+        {{ shared_macros.response_method(body_spec, is_async=True)|indent(8) }}
+
+        {% endif %}{#  method.http_options and not method.client_streaming and not method.server_streaming and not method.lro and not method.extended_lro and not method.paged_result_field #}
         async def __call__(self,
                     request: {{method.input.ident}}, *,
                     retry: OptionalRetry=gapic_v1.method.DEFAULT,
                     timeout: Optional[float]=None,
                     metadata: Sequence[Tuple[str, str]]=(),
-                    {# TODO(b/362949446): Update the return type as we implement this for different method types. #}
-                    ) -> None:
+                    {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2168): Update return type for server streaming method. #}
+                    {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2169): Update return type for client streaming method. #}
+                    {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2170): Update the return type for long running operation method. #}
+                    {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2171): Update the return type for pager method. #}
+                    ){% if not method.void %} -> {% if not method.server_streaming %}{{method.output.ident}}{% else %}None{% endif %}{% endif %}:
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2168): Implement server streaming method. #}
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2169): Implement client streaming method. #}
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2170): Implement long running operation method. #}
+        {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2171): Implement pager method. #}
+         {% if method.http_options and not method.client_streaming and not method.server_streaming and not method.lro and not method.extended_lro and not method.paged_result_field %}
+            r"""Call the {{- ' ' -}}
+            {{ (method.name|snake_case).replace('_',' ')|wrap(
+                    width=70, offset=45, indent=8) }}
+            {{- ' ' -}} method over HTTP.
+
+            Args:
+                request (~.{{ method.input.ident }}):
+                    The request object.{{ ' ' }}
+                    {{- method.input.meta.doc|rst(width=72, indent=16, nl=False) }}
+                retry (google.api_core.retry_async.AsyncRetry): Designation of what errors, if any,
+                    should be retried.
+                timeout (float): The timeout for this request.
+                metadata (Sequence[Tuple[str, str]]): Strings which should be
+                    sent along with the request as metadata.
+            {% if not method.void %}
+
+            Returns:
+                ~.{{ method.output.ident }}:
+                    {{ method.output.meta.doc|rst(width=72, indent=16) }}
+            {% endif %}
+            """
+
+            {{ shared_macros.rest_call_method_common(body_spec, method.name, service.name, is_async=True)|indent(8) }}
+
+            {% if not method.void %}
+            # Return the response
+            resp = {{method.output.ident}}()
+            {% if method.output.ident.is_proto_plus_type %}
+            pb_resp = {{method.output.ident}}.pb(resp)
+            {% else %}
+            pb_resp = resp
+            {% endif %}
+            content = await response.read()
+            json_format.Parse(content, pb_resp, ignore_unknown_fields=True)
+            return resp
+
+            {% endif %}{# method.void #}
+
+         {% else %}
                 raise NotImplementedError(
                     "Method {{ method.name }} is not available over REST transport"
                 )
+        {% endif %}{#  method.http_options and not method.client_streaming and not method.server_streaming and not method.lro and not method.extended_lro and not method.paged_result_field #}
 
     {% endfor %}
     {% for method in service.methods.values()|sort(attribute="name") %}

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

@@ -1051,6 +1051,9 @@ def test_{{ method_name }}_raw_page_lro():
 {% with method_name = method.safe_name|snake_case + "_unary" if method.extended_lro and not full_extended_lro else method.name|snake_case, method_output = method.extended_lro.operation_type if method.extended_lro and not full_extended_lro else method.output %}{% if method.http_options %}
 {# TODO(kbandes): remove this if condition when lro and client streaming are supported. #}
 {% if not method.client_streaming %}
+{# TODO(https://github.com/googleapis/gapic-generator-python/issues/2168): Remove unit test for server streaming method. #}
+{# TODO(https://github.com/googleapis/gapic-generator-python/issues/2170): Remove unit test for long running operation method. #}
+{# TODO(https://github.com/googleapis/gapic-generator-python/issues/2171): Remove unit test for pager method. #}
 {# NOTE: This guard is added to avoid generating duplicate tests for methods which are tested elsewhere. As we implement each of the api methods
  # in the `macro::call_success_test`, the case will be removed from this condition below.
  # TODO(https://github.com/googleapis/gapic-generator-python/issues/2143): Remove the test `test_{{ method_name }}_rest` from here once the linked issue is resolved.
@@ -1940,7 +1943,7 @@ def test_unsupported_parameter_rest_asyncio():
  # There are no plans to add support for client streaming.
 #}
 {% macro is_rest_unsupported_method(method, is_async) %}
-{%- if method.client_streaming or is_async -%}
+{%- if method.client_streaming or (is_async and (method.server_streaming or method.lro or method.extended_lro or method.paged_result_field)) -%}
 {{'True'}}
 {%- else -%}
 {{'False'}}
@@ -2083,6 +2086,9 @@ def test_initialize_client_w_{{transport_name}}():
  # (method.extended_lro and not full_extended_lro)
 #}
 {% set method_output = method.output %}
+{# TODO(https://github.com/googleapis/gapic-generator-python/issues/2168): Add unit test for server streaming method. #}
+{# TODO(https://github.com/googleapis/gapic-generator-python/issues/2170): Add unit test for long running operation method. #}
+{# TODO(https://github.com/googleapis/gapic-generator-python/issues/2171): Add unit test for pager method. #}
 {# TODO(https://github.com/googleapis/gapic-generator-python/issues/2143): Update the guard below as we add support for each method, and keep it in sync with the guard in
  # `rest_required_tests`, which should be the exact opposite. Remove it once we have all the methods supported in async rest transport that are supported in sync rest transport.
  #}
@@ -2230,10 +2236,10 @@ def test_initialize_client_w_{{transport_name}}():
         json_return_value = json_format.MessageToJson(return_value)
         {% endif %}{# method.void #}
         {% if is_async %}
-        response_value.read = mock.AsyncMock(return_value=b'{}')
+        response_value.read = mock.AsyncMock(return_value=json_return_value.encode('UTF-8'))
         {% else %}{# is_async #}
         response_value.content = json_return_value.encode('UTF-8')
-        {% endif %}
+        {% endif %}{# is_async #}
         req.return_value = response_value
         response = {{ await_prefix }}client.{{ method_name }}(request)
 

noxfile.py

@@ -444,7 +444,7 @@ def showcase_unit_w_rest_async(
         # 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@add-support-for-async-authorized-session-api")
+        session.install('--no-cache-dir', '--force-reinstall', "google-auth@git+https://github.com/googleapis/google-auth-library-python.git")
         session.install("aiohttp")
         run_showcase_unit_tests(session)