Fix bug related to augmenting client call details metatadata (#17)

Use public interface for re-creating ClientCallDetails with updated metadata in interceptor

ChangeLog

@@ -1,3 +1,6 @@
+* 0.5.1:
+- Fix bug related to usage of private grpc._interceptor._ClientCallDetails class
+
 * 0.5.0:
 - Google Ads v0_6 release.
 - Updating add_campaign_targeting_criteria.py example to add

google/ads/google_ads/__init__.py

@@ -18,4 +18,4 @@
 import google.ads.google_ads.errors
 
 
-VERSION = '0.4.0'
+VERSION = '0.5.1'

google/ads/google_ads/client.py

@@ -16,6 +16,7 @@
 import logging
 import os
 import yaml
+from collections import namedtuple
 
 import google.api_core.grpc_helpers
 import google.auth.transport.requests
@@ -346,6 +347,14 @@ def __init__(self, developer_token, login_customer_id):
             ('login-customer-id', login_customer_id) if login_customer_id
             else None)
 
+    def _update_client_call_details_metadata(
+            self, client_call_details, metadata):
+        client_call_details = _ClientCallDetails(
+            client_call_details.method, client_call_details.timeout, metadata,
+            client_call_details.credentials)
+
+        return client_call_details
+
     def intercept_unary_unary(self, continuation, client_call_details, request):
         """Intercepts and appends custom metadata.
 
@@ -361,14 +370,22 @@ def intercept_unary_unary(self, continuation, client_call_details, request):
         if self.login_customer_id_meta:
             metadata.append(self.login_customer_id_meta)
 
-        client_call_details = grpc._interceptor._ClientCallDetails(
-            client_call_details.method, client_call_details.timeout, metadata,
-            client_call_details.credentials
-        )
+        client_call_details = self._update_client_call_details_metadata(
+            client_call_details,
+            metadata)
 
         return continuation(client_call_details, request)
 
 
+class _ClientCallDetails(
+        namedtuple(
+            '_ClientCallDetails',
+            ('method', 'timeout', 'metadata', 'credentials')),
+        grpc.ClientCallDetails):
+    """An wrapper class for initializing a new ClientCallDetails instance."""
+    pass
+
+
 def _get_version(name):
     """Returns the given API version.
 

setup.py

@@ -33,7 +33,7 @@
 
 setup(
     name='google-ads',
-    version='0.5.0',
+    version='0.5.1',
     author='Google LLC',
     author_email='googleapis-packages@google.com',
     classifiers=[

tests/client_test.py

@@ -304,3 +304,80 @@ def test_get_type_invalid_version(self):
         self.assertRaises(
             ValueError, google.ads.google_ads.client.GoogleAdsClient.get_type,
             'GoogleAdsFailure', version='v0_bad')
+
+
+class MetadataInterceptorTest(TestCase):
+
+    def setUp(self):
+        self.mock_developer_token = '1234567890'
+        self.mock_login_customer_id = '0987654321'
+
+    def test_init(self):
+        interceptor = google.ads.google_ads.client.MetadataInterceptor(
+            self.mock_developer_token,
+            self.mock_login_customer_id)
+
+        self.assertEqual(
+            interceptor.developer_token_meta,
+            ('developer-token', self.mock_developer_token))
+
+        self.assertEqual(
+            interceptor.login_customer_id_meta,
+            ('login-customer-id', self.mock_login_customer_id)
+        )
+
+    def test_init_no_login_customer_id(self):
+        interceptor = google.ads.google_ads.client.MetadataInterceptor(
+            self.mock_developer_token,
+            None)
+
+        self.assertEqual(
+            interceptor.developer_token_meta,
+            ('developer-token', self.mock_developer_token))
+
+        self.assertEqual(
+            interceptor.login_customer_id_meta,
+            None
+        )
+
+    def test_update_client_call_details_metadata(self):
+        interceptor = google.ads.google_ads.client.MetadataInterceptor(
+            self.mock_developer_token,
+            self.mock_login_customer_id)
+
+        mock_metadata = list([('test-key', 'test-value')])
+        mock_client_call_details = mock.Mock()
+
+        client_call_details = interceptor._update_client_call_details_metadata(
+            mock_client_call_details, mock_metadata)
+
+        self.assertEqual(client_call_details.metadata, mock_metadata)
+
+    def test_intercept_unary_unary(self):
+        interceptor = google.ads.google_ads.client.MetadataInterceptor(
+            self.mock_developer_token,
+            self.mock_login_customer_id)
+
+        mock_continuation = mock.Mock(return_value=None)
+        mock_client_call_details = mock.Mock()
+        mock_client_call_details.method = 'test/method'
+        mock_client_call_details.timeout = 5
+        mock_client_call_details.metadata = [('apples', 'oranges')]
+        mock_request = mock.Mock()
+
+        with mock.patch.object(
+            interceptor,
+            '_update_client_call_details_metadata',
+            wraps=interceptor._update_client_call_details_metadata
+        ) as mock_updater:
+            interceptor.intercept_unary_unary(
+                mock_continuation,
+                mock_client_call_details,
+                mock_request)
+
+            mock_updater.assert_called_once_with(
+                mock_client_call_details, [mock_client_call_details.metadata[0],
+                interceptor.developer_token_meta,
+                interceptor.login_customer_id_meta])
+
+            mock_continuation.assert_called_once()