@@ -1403,6 +1403,12 @@ async def check_valid_creds(
         # Done; return the response.
         return response
 
+    async def __aenter__(self):
+        return self
+
+    async def __aexit__(self, exc_type, exc, tb):
+        await self.transport.close()
+
 
 try:
     DEFAULT_CLIENT_INFO = gapic_v1.client_info.ClientInfo(
 
@@ -388,10 +388,7 @@ def __init__(
                 client_cert_source_for_mtls=client_cert_source_func,
                 quota_project_id=client_options.quota_project_id,
                 client_info=client_info,
-                always_use_jwt_access=(
-                    Transport == type(self).get_transport_class("grpc")
-                    or Transport == type(self).get_transport_class("grpc_asyncio")
-                ),
+                always_use_jwt_access=True,
             )
 
     def get_data_source(
@@ -1519,6 +1516,19 @@ def check_valid_creds(
         # Done; return the response.
         return response
 
+    def __enter__(self):
+        return self
+
+    def __exit__(self, type, value, traceback):
+        """Releases underlying transport's resources.
+
+        .. warning::
+            ONLY use as a context manager if the transport is NOT shared
+            with other clients! Exiting the with block will CLOSE the transport
+            and may cause errors in other clients!
+        """
+        self.transport.close()
+
 
 try:
     DEFAULT_CLIENT_INFO = gapic_v1.client_info.ClientInfo(
 
@@ -328,6 +328,15 @@ def _prep_wrapped_messages(self, client_info):
             ),
         }
 
+    def close(self):
+        """Closes resources associated with the transport.
+
+       .. warning::
+            Only call this method if the transport is NOT shared
+            with other clients - this may cause errors in other clients!
+        """
+        raise NotImplementedError()
+
     @property
     def get_data_source(
         self,
 
@@ -631,5 +631,8 @@ def check_valid_creds(
             )
         return self._stubs["check_valid_creds"]
 
+    def close(self):
+        self.grpc_channel.close()
+
 
 __all__ = ("DataTransferServiceGrpcTransport",)
@@ -650,5 +650,8 @@ def check_valid_creds(
             )
         return self._stubs["check_valid_creds"]
 
+    def close(self):
+        return self.grpc_channel.close()
+
 
 __all__ = ("DataTransferServiceGrpcAsyncIOTransport",)
@@ -236,6 +236,7 @@ class DataRefreshType(proto.Enum):
 
 class GetDataSourceRequest(proto.Message):
     r"""A request to get data source info.
+
     Attributes:
         name (str):
             Required. The field will contain name of the resource
@@ -275,6 +276,7 @@ class ListDataSourcesRequest(proto.Message):
 
 class ListDataSourcesResponse(proto.Message):
     r"""Returns list of supported data sources and their metadata.
+
     Attributes:
         data_sources (Sequence[google.cloud.bigquery_datatransfer_v1.types.DataSource]):
             List of supported data sources and their
@@ -419,6 +421,7 @@ class UpdateTransferConfigRequest(proto.Message):
 
 class GetTransferConfigRequest(proto.Message):
     r"""A request to get data transfer information.
+
     Attributes:
         name (str):
             Required. The field will contain name of the resource
@@ -447,6 +450,7 @@ class DeleteTransferConfigRequest(proto.Message):
 
 class GetTransferRunRequest(proto.Message):
     r"""A request to get data transfer run information.
+
     Attributes:
         name (str):
             Required. The field will contain name of the resource
@@ -461,6 +465,7 @@ class GetTransferRunRequest(proto.Message):
 
 class DeleteTransferRunRequest(proto.Message):
     r"""A request to delete data transfer run information.
+
     Attributes:
         name (str):
             Required. The field will contain name of the resource
@@ -504,6 +509,7 @@ class ListTransferConfigsRequest(proto.Message):
 
 class ListTransferConfigsResponse(proto.Message):
     r"""The returned list of pipelines in the project.
+
     Attributes:
         transfer_configs (Sequence[google.cloud.bigquery_datatransfer_v1.types.TransferConfig]):
             Output only. The stored pipeline transfer
@@ -568,6 +574,7 @@ class RunAttempt(proto.Enum):
 
 class ListTransferRunsResponse(proto.Message):
     r"""The returned list of pipelines in the project.
+
     Attributes:
         transfer_runs (Sequence[google.cloud.bigquery_datatransfer_v1.types.TransferRun]):
             Output only. The stored pipeline transfer
@@ -624,6 +631,7 @@ class ListTransferLogsRequest(proto.Message):
 
 class ListTransferLogsResponse(proto.Message):
     r"""The returned list transfer run messages.
+
     Attributes:
         transfer_messages (Sequence[google.cloud.bigquery_datatransfer_v1.types.TransferMessage]):
             Output only. The stored pipeline transfer
@@ -678,6 +686,7 @@ class CheckValidCredsResponse(proto.Message):
 
 class ScheduleTransferRunsRequest(proto.Message):
     r"""A request to schedule transfer runs for a time range.
+
     Attributes:
         parent (str):
             Required. Transfer configuration name in the form:
@@ -698,6 +707,7 @@ class ScheduleTransferRunsRequest(proto.Message):
 
 class ScheduleTransferRunsResponse(proto.Message):
     r"""A response to schedule transfer runs for a time range.
+
     Attributes:
         runs (Sequence[google.cloud.bigquery_datatransfer_v1.types.TransferRun]):
             The transfer runs that were scheduled.
@@ -708,6 +718,7 @@ class ScheduleTransferRunsResponse(proto.Message):
 
 class StartManualTransferRunsRequest(proto.Message):
     r"""A request to start manual transfer runs.
+
     Attributes:
         parent (str):
             Transfer configuration name in the form:
@@ -759,6 +770,7 @@ class TimeRange(proto.Message):
 
 class StartManualTransferRunsResponse(proto.Message):
     r"""A response to start manual transfer runs.
+
     Attributes:
         runs (Sequence[google.cloud.bigquery_datatransfer_v1.types.TransferRun]):
             The transfer runs that were created.
 
@@ -67,6 +67,7 @@ class EmailPreferences(proto.Message):
 
 class ScheduleOptions(proto.Message):
     r"""Options customizing the data transfer schedule.
+
     Attributes:
         disable_auto_scheduling (bool):
             If true, automatic scheduling of data
@@ -205,6 +206,7 @@ class TransferConfig(proto.Message):
 
 class TransferRun(proto.Message):
     r"""Represents a data transfer run.
+
     Attributes:
         name (str):
             The resource name of the transfer run. Transfer run names
 
@@ -29,6 +29,7 @@
 from google.api_core import gapic_v1
 from google.api_core import grpc_helpers
 from google.api_core import grpc_helpers_async
+from google.api_core import path_template
 from google.auth import credentials as ga_credentials
 from google.auth.exceptions import MutualTLSChannelError
 from google.cloud.bigquery_datatransfer_v1.services.data_transfer_service import (
@@ -4589,6 +4590,9 @@ def test_data_transfer_service_base_transport():
         with pytest.raises(NotImplementedError):
             getattr(transport, method)(request=object())
 
+    with pytest.raises(NotImplementedError):
+        transport.close()
+
 
 @requires_google_auth_gte_1_25_0
 def test_data_transfer_service_base_transport_with_credentials_file():
@@ -5117,3 +5121,49 @@ def test_client_withDEFAULT_CLIENT_INFO():
             credentials=ga_credentials.AnonymousCredentials(), client_info=client_info,
         )
         prep.assert_called_once_with(client_info)
+
+
+@pytest.mark.asyncio
+async def test_transport_close_async():
+    client = DataTransferServiceAsyncClient(
+        credentials=ga_credentials.AnonymousCredentials(), transport="grpc_asyncio",
+    )
+    with mock.patch.object(
+        type(getattr(client.transport, "grpc_channel")), "close"
+    ) as close:
+        async with client:
+            close.assert_not_called()
+        close.assert_called_once()
+
+
+def test_transport_close():
+    transports = {
+        "grpc": "_grpc_channel",
+    }
+
+    for transport, close_name in transports.items():
+        client = DataTransferServiceClient(
+            credentials=ga_credentials.AnonymousCredentials(), transport=transport
+        )
+        with mock.patch.object(
+            type(getattr(client.transport, close_name)), "close"
+        ) as close:
+            with client:
+                close.assert_not_called()
+            close.assert_called_once()
+
+
+def test_client_ctx():
+    transports = [
+        "grpc",
+    ]
+    for transport in transports:
+        client = DataTransferServiceClient(
+            credentials=ga_credentials.AnonymousCredentials(), transport=transport
+        )
+        # Test client calls underlying transport.
+        with mock.patch.object(type(client.transport), "close") as close:
+            close.assert_not_called()
+            with client:
+                pass
+            close.assert_called()
Original file line number	Diff line number	Diff line change
`@@ -631,5 +631,8 @@ def check_valid_creds(`
`631`	`631`	`)`
`632`	`632`	`return self._stubs["check_valid_creds"]`
`633`	`633`
	`634`	`+ def close(self):`
	`635`	`+ self.grpc_channel.close()`
	`636`	`+`
`634`	`637`
`635`	`638`	`__all__ = ("DataTransferServiceGrpcTransport",)`
Original file line number	Diff line number	Diff line change
`@@ -650,5 +650,8 @@ def check_valid_creds(`
`650`	`650`	`)`
`651`	`651`	`return self._stubs["check_valid_creds"]`
`652`	`652`
	`653`	`+ def close(self):`
	`654`	`+ return self.grpc_channel.close()`
	`655`	`+`
`653`	`656`
`654`	`657`	`__all__ = ("DataTransferServiceGrpcAsyncIOTransport",)`