feat: add quota_project, credentials_file, and scopes support (#1022)

Add support for client options:
* quota_project_id
* credentials_file
* scopes

These are only available when default credentials are used.

googleapiclient/_auth.py

@@ -38,12 +38,27 @@
     HAS_OAUTH2CLIENT = False
 
 
-def default_credentials():
+def credentials_from_file(filename, scopes=None, quota_project_id=None):
+    """Returns credentials loaded from a file."""
+    if HAS_GOOGLE_AUTH:
+        credentials, _ = google.auth.load_credentials_from_file(filename, scopes=scopes, quota_project_id=quota_project_id)
+        return credentials
+    else:
+        raise EnvironmentError(
+        "client_options.credentials_file is only supported in google-auth.")
+
+
+def default_credentials(scopes=None, quota_project_id=None):
     """Returns Application Default Credentials."""
     if HAS_GOOGLE_AUTH:
-        credentials, _ = google.auth.default()
+        credentials, _ = google.auth.default(scopes=scopes, quota_project_id=quota_project_id)
         return credentials
     elif HAS_OAUTH2CLIENT:
+        if scopes is not None or quota_project_id is not None:
+            raise EnvironmentError(
+                "client_options.scopes and client_options.quota_project_id are not supported in oauth2client."
+                "Please install google-auth."
+            )
         return oauth2client.client.GoogleCredentials.get_application_default()
     else:
         raise EnvironmentError(

googleapiclient/discovery.py

@@ -30,6 +30,7 @@
 # Standard library imports
 import copy
 from collections import OrderedDict
+
 try:
     from email.generator import BytesGenerator
 except ImportError:
@@ -260,14 +261,17 @@ def build(
     else:
         discovery_http = http
 
-    for discovery_url in \
-            _discovery_service_uri_options(discoveryServiceUrl, version):
+    for discovery_url in _discovery_service_uri_options(discoveryServiceUrl, version):
         requested_url = uritemplate.expand(discovery_url, params)
 
         try:
             content = _retrieve_discovery_doc(
-                requested_url, discovery_http, cache_discovery, cache,
-                developerKey, num_retries=num_retries
+                requested_url,
+                discovery_http,
+                cache_discovery,
+                cache,
+                developerKey,
+                num_retries=num_retries,
             )
             return build_from_document(
                 content,
@@ -308,13 +312,15 @@ def _discovery_service_uri_options(discoveryServiceUrl, version):
     # V1 Discovery won't work if the requested version is None
     if discoveryServiceUrl == V1_DISCOVERY_URI and version is None:
         logger.warning(
-            "Discovery V1 does not support empty versions. Defaulting to V2...")
+            "Discovery V1 does not support empty versions. Defaulting to V2..."
+        )
         urls.pop(0)
     return list(OrderedDict.fromkeys(urls))
 
 
-def _retrieve_discovery_doc(url, http, cache_discovery,
-    cache=None, developerKey=None, num_retries=1):
+def _retrieve_discovery_doc(
+    url, http, cache_discovery, cache=None, developerKey=None, num_retries=1
+):
     """Retrieves the discovery_doc from cache or the internet.
 
   Args:
@@ -444,8 +450,20 @@ def build_from_document(
       setting up mutual TLS channel.
   """
 
-    if http is not None and credentials is not None:
-        raise ValueError("Arguments http and credentials are mutually exclusive.")
+    if client_options is None:
+        client_options = google.api_core.client_options.ClientOptions()
+    if isinstance(client_options, six.moves.collections_abc.Mapping):
+        client_options = google.api_core.client_options.from_dict(client_options)
+
+    if http is not None:
+        # if http is passed, the user cannot provide credentials
+        banned_options = [
+            (credentials, "credentials"),
+            (client_options.credentials_file, "client_options.credentials_file"),
+        ]
+        for option, name in banned_options:
+            if option is not None:
+                raise ValueError("Arguments http and {} are mutually exclusive".format(name))
 
     if isinstance(service, six.string_types):
         service = json.loads(service)
@@ -463,11 +481,8 @@ def build_from_document(
 
     # If an API Endpoint is provided on client options, use that as the base URL
     base = urljoin(service["rootUrl"], service["servicePath"])
-    if client_options:
-        if isinstance(client_options, six.moves.collections_abc.Mapping):
-            client_options = google.api_core.client_options.from_dict(client_options)
-        if client_options.api_endpoint:
-            base = client_options.api_endpoint
+    if client_options.api_endpoint:
+        base = client_options.api_endpoint
 
     schema = Schemas(service)
 
@@ -483,13 +498,30 @@ def build_from_document(
         # If so, then the we need to setup authentication if no developerKey is
         # specified.
         if scopes and not developerKey:
+            # Make sure the user didn't pass multiple credentials
+            if client_options.credentials_file and credentials:
+                raise google.api_core.exceptions.DuplicateCredentialArgs(
+                    "client_options.credentials_file and credentials are mutually exclusive."
+            )
+            # Check for credentials file via client options
+            if client_options.credentials_file:
+                credentials = _auth.credentials_from_file(
+                    client_options.credentials_file,
+                    scopes=client_options.scopes,
+                    quota_project_id=client_options.quota_project_id,
+                )
             # If the user didn't pass in credentials, attempt to acquire application
             # default credentials.
             if credentials is None:
-                credentials = _auth.default_credentials()
+                credentials = _auth.default_credentials(
+                    scopes=client_options.scopes,
+                    quota_project_id=client_options.quota_project_id,
+                )
 
             # The credentials need to be scoped.
-            credentials = _auth.with_scopes(credentials, scopes)
+            # If the user provided scopes via client_options don't override them
+            if not client_options.scopes:
+                credentials = _auth.with_scopes(credentials, scopes)
 
         # If credentials are provided, create an authorized http instance;
         # otherwise, skip authentication.
@@ -519,7 +551,9 @@ def build_from_document(
                 and client_options.client_encrypted_cert_source
             ):
                 client_cert_to_use = client_options.client_encrypted_cert_source
-            elif adc_cert_path and adc_key_path and mtls.has_default_client_cert_source():
+            elif (
+                adc_cert_path and adc_key_path and mtls.has_default_client_cert_source()
+            ):
                 client_cert_to_use = mtls.default_client_encrypted_cert_source(
                     adc_cert_path, adc_key_path
                 )

noxfile.py

@@ -44,7 +44,7 @@ def lint(session):
     )
 
 
-@nox.session(python=["2.7", "3.5", "3.6", "3.7"])
+@nox.session(python=["2.7", "3.5", "3.6", "3.7", "3.8"])
 @nox.parametrize(
     "oauth2client",
     [

setup.py

@@ -41,7 +41,7 @@
     "httplib2>=0.9.2,<1dev",
     "google-auth>=1.16.0",
     "google-auth-httplib2>=0.0.3",
-    "google-api-core>=1.18.0,<2dev",
+    "google-api-core>=1.21.0,<2dev",
     "six>=1.6.1,<2dev",
     "uritemplate>=3.0.0,<4dev",
 ]

tests/test__auth.py

@@ -40,6 +40,35 @@ def test_default_credentials(self):
 
             self.assertEqual(credentials, mock.sentinel.credentials)
 
+    def test_credentials_from_file(self):
+        with mock.patch(
+            "google.auth.load_credentials_from_file", autospec=True
+        ) as default:
+            default.return_value = (mock.sentinel.credentials, mock.sentinel.project)
+
+            credentials = _auth.credentials_from_file("credentials.json")
+
+            self.assertEqual(credentials, mock.sentinel.credentials)
+            default.assert_called_once_with(
+                "credentials.json", scopes=None, quota_project_id=None
+            )
+
+    def test_default_credentials_with_scopes(self):
+        with mock.patch("google.auth.default", autospec=True) as default:
+            default.return_value = (mock.sentinel.credentials, mock.sentinel.project)
+            credentials = _auth.default_credentials(scopes=["1", "2"])
+
+            default.assert_called_once_with(scopes=["1", "2"], quota_project_id=None)
+            self.assertEqual(credentials, mock.sentinel.credentials)
+
+    def test_default_credentials_with_quota_project(self):
+        with mock.patch("google.auth.default", autospec=True) as default:
+            default.return_value = (mock.sentinel.credentials, mock.sentinel.project)
+            credentials = _auth.default_credentials(quota_project_id="my-project")
+
+            default.assert_called_once_with(scopes=None, quota_project_id="my-project")
+            self.assertEqual(credentials, mock.sentinel.credentials)
+
     def test_with_scopes_non_scoped(self):
         credentials = mock.Mock(spec=google.auth.credentials.Credentials)
 
@@ -95,6 +124,16 @@ def test_default_credentials(self):
 
             self.assertEqual(credentials, mock.sentinel.credentials)
 
+    def test_credentials_from_file(self):
+        with self.assertRaises(EnvironmentError):
+            credentials = _auth.credentials_from_file("credentials.json")
+
+    def test_default_credentials_with_scopes_and_quota_project(self):
+        with self.assertRaises(EnvironmentError):
+            credentials = _auth.default_credentials(
+                scopes=["1", "2"], quota_project_id="my-project"
+            )
+
     def test_with_scopes_non_scoped(self):
         credentials = mock.Mock(spec=oauth2client.client.Credentials)