Core: Add client options.

api_core/google/api_core/client_options.py

@@ -0,0 +1,48 @@
+# Copyright 2019 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Client options class.
+
+Client options provide a consistent interface for user options to be defined
+across clients.
+"""
+
+
+class ClientOptions(object):
+    """Client Options used to set options on clients.
+
+    Args:
+        api_endpoint (str): The desired API endpoint, e.g., compute.googleapis.com
+    """
+
+    def __init__(self, api_endpoint=None):
+        self.api_endpoint = api_endpoint
+
+
+def from_dict(options):
+    """Construct a client options object from a dictionary.
+
+    Args:
+        options (dict): A dictionary with client options.
+    """
+
+    client_options = ClientOptions()
+
+    for key, value in options.items():
+        if hasattr(client_options, key):
+            setattr(client_options, key, value)
+        else:
+            raise ValueError("ClientOptions does not accept an option '" + key + "'")
+
+    return client_options

api_core/tests/unit/test_client_options.py

@@ -0,0 +1,36 @@
+# Copyright 2017 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import pytest
+
+from google.api_core import client_options
+
+
+def test_constructor():
+    options = client_options.ClientOptions(api_endpoint="foo.googleapis.com")
+
+    assert options.api_endpoint == "foo.googleapis.com"
+
+
+def test_from_dict():
+    options = client_options.from_dict({"api_endpoint": "foo.googleapis.com"})
+
+    assert options.api_endpoint == "foo.googleapis.com"
+
+
+def test_from_dict_bad_argument():
+    with pytest.raises(ValueError):
+        client_options.from_dict(
+            {"api_endpoint": "foo.googleapis.com", "bad_arg": "1234"}
+        )

iot/google/cloud/iot_v1/gapic/device_manager_client.py

@@ -22,6 +22,7 @@
 
 from google.oauth2 import service_account
 import google.api_core.gapic_v1.client_info
+import google.api_core.client_options
 import google.api_core.gapic_v1.config
 import google.api_core.gapic_v1.method
 import google.api_core.gapic_v1.routing_header
@@ -112,6 +113,7 @@ def __init__(
         credentials=None,
         client_config=None,
         client_info=None,
+        client_options=None,
     ):
         """Constructor.
 
@@ -142,6 +144,9 @@ def __init__(
                 API requests. If ``None``, then default info will be used.
                 Generally, you only need to set this if you're developing
                 your own client library.
+            client_options (Union[dict, google.api_core.client_options.ClientOptions):
+                Client options used to set user options on the client. API Endpoint
+                should be set through client_options.
         """
         # Raise deprecation warnings for things we want to go away.
         if client_config is not None:
@@ -160,6 +165,13 @@ def __init__(
                 stacklevel=2,
             )
 
+        api_endpoint = self.SERVICE_ADDRESS
+        if client_options:
+            if type(client_options) == dict:
+                client_options = google.api_core.client_options.from_dict(client_options)
+            if client_options.api_endpoint:
+                api_endpoint = client_options.api_endpoint
+
         # Instantiate the transport.
         # The transport is responsible for handling serialization and
         # deserialization and actually sending data to the service.
@@ -168,6 +180,7 @@ def __init__(
                 self.transport = transport(
                     credentials=credentials,
                     default_class=device_manager_grpc_transport.DeviceManagerGrpcTransport,
+                    address=api_endpoint,
                 )
             else:
                 if credentials:
@@ -178,7 +191,7 @@ def __init__(
                 self.transport = transport
         else:
             self.transport = device_manager_grpc_transport.DeviceManagerGrpcTransport(
-                address=self.SERVICE_ADDRESS, channel=channel, credentials=credentials
+                address=api_endpoint, channel=channel, credentials=credentials
             )
 
         if client_info is None: