feedback changes

Author: mhaseebtariq

pandas/io/gbq.py

@@ -171,25 +171,28 @@ def get_application_default_credentials(self):
         This method tries to retrieve the "default application credentials"
         Could be useful for running code on Google Cloud Platform
         """
-        from oauth2client.client import AccessTokenRefreshError
-        try:
-            from googleapiclient.discovery import build
-            from googleapiclient.errors import HttpError
-        except:
-            from apiclient.discovery import build
-            from apiclient.errors import HttpError
+        oauth2client_library_imported = False
         try:
             from oauth2client.client import GoogleCredentials
+            from oauth2client.client import AccessTokenRefreshError
             from oauth2client.client import HttpAccessTokenRefreshError
             from oauth2client.client import ApplicationDefaultCredentialsError
+            oauth2client_library_imported = True
+            from googleapiclient.discovery import build
+            from googleapiclient.errors import HttpError
         except ImportError:
+            from apiclient.discovery import build
+            from apiclient.errors import HttpError
+
+        if not oauth2client_library_imported:
             return None
 
         credentials = None
         try:
             credentials = GoogleCredentials.get_application_default()
         except ApplicationDefaultCredentialsError:
             return None
+
         # Check if the application has rights to the BigQuery project
         bigquery_service = build('bigquery', 'v2', credentials=credentials)
         jobs = bigquery_service.jobs()
@@ -617,14 +620,16 @@ def read_gbq(query, project_id=None, index_col=None, col_order=None,
     https://developers.google.com/api-client-library/python/apis/bigquery/v2
 
     Authentication to the Google BigQuery service is via OAuth 2.0.
-    If "private_key" is not provided:
-        By default "application default credentials" are used [new behavior]
-        If default application credentials are not found or are restrictive -
-        User account credentials are used. In this case - you will be asked to
+    - If "private_key" is not provided:
+        By default "application default credentials" are used.
+
+        .. versionadded:: 0.19.0
+
+        If default application credentials are not found or are restrictive,
+        user account credentials are used. In this case, you will be asked to
         grant permissions for product name 'pandas GBQ'.
-    If "private_key" is provided:
-        It is also posible to authenticate via service account credentials
-        by using this parameter.
+    - If "private_key" is provided:
+        Service account credentials will be used to authenticate.
 
     Parameters
     ----------
@@ -731,14 +736,17 @@ def to_gbq(dataframe, destination_table, project_id, chunksize=10000,
     Documentation is available at
     https://developers.google.com/api-client-library/python/apis/bigquery/v2
 
-    If "private_key" is not provided:
-        By default "application default credentials" are used [new behavior]
-        If default application credentials are not found or are restrictive -
-        User account credentials are used. In this case - you will be asked to
+    Authentication to the Google BigQuery service is via OAuth 2.0.
+    - If "private_key" is not provided:
+        By default "application default credentials" are used.
+
+        .. versionadded:: 0.19.0
+
+        If default application credentials are not found or are restrictive,
+        user account credentials are used. In this case, you will be asked to
         grant permissions for product name 'pandas GBQ'.
-    If "private_key" is provided:
-        It is also posible to authenticate via service account credentials
-        by using this parameter.
+    - If "private_key" is provided:
+        Service account credentials will be used to authenticate.
 
     Parameters
     ----------

pandas/io/tests/test_gbq.py

@@ -56,8 +56,7 @@ def _skip_if_no_private_key_contents():
         _skip_if_no_private_key_contents()
 
 
-def _skip_if_get_correct_default_credentials(can=False):
-    got_credentials = False
+def _check_if_can_get_correct_default_credentials():
     try:
         from oauth2client.client import GoogleCredentials
         from apiclient.discovery import build
@@ -66,13 +65,19 @@ def _skip_if_get_correct_default_credentials(can=False):
         jobs = bigquery_service.jobs()
         job_data = {'configuration': {'query': {'query': 'SELECT 1'}}}
         jobs.insert(projectId=PROJECT_ID, body=job_data).execute()
-        got_credentials = True
+        return True
     except:
-        pass
-    if can and got_credentials:
+        return False
+
+
+def _skip_if_cant_get_correct_default_credentials():
+    if not _check_if_can_get_correct_default_credentials():
         raise nose.SkipTest("Cannot get default_credentials "
                             "from the environment!")
-    if (not can) and (not got_credentials):
+
+
+def _skip_if_can_get_correct_default_credentials():
+    if _check_if_can_get_correct_default_credentials():
         raise nose.SkipTest("Can get default_credentials "
                             "from the environment!")
 
@@ -240,12 +245,12 @@ def test_should_be_able_to_get_results_from_query(self):
         self.assertTrue(pages is not None)
 
     def test_get_application_default_credentials_does_not_throw_error(self):
-        _skip_if_get_correct_default_credentials(can=True)
+        _skip_if_can_get_correct_default_credentials()
         credentials = self.sut.get_application_default_credentials()
         self.assertIsNone(credentials)
 
     def test_get_application_default_credentials_returns_credentials(self):
-        _skip_if_get_correct_default_credentials(can=False)
+        _skip_if_cant_get_correct_default_credentials()
         from oauth2client.client import GoogleCredentials
         credentials = self.sut.get_application_default_credentials()
         self.assertTrue(isinstance(credentials, GoogleCredentials))