Making Connection()-s act as proxies for data stored in Client()-s

bigquery/google/cloud/bigquery/_http.py

@@ -18,7 +18,11 @@
 
 
 class Connection(_http.JSONConnection):
-    """A connection to Google BigQuery via the JSON REST API."""
+    """A connection to Google BigQuery via the JSON REST API.
+
+    :type client: :class:`~google.cloud.bigquery.client.Client`
+    :param client: The client that owns the current connection.
+    """
 
     API_BASE_URL = 'https://www.googleapis.com'
     """The base of the API call URL."""
@@ -28,7 +32,3 @@ class Connection(_http.JSONConnection):
 
     API_URL_TEMPLATE = '{api_base_url}/bigquery/{api_version}{path}'
     """A template for the URL of a particular API call."""
-
-    SCOPE = ('https://www.googleapis.com/auth/bigquery',
-             'https://www.googleapis.com/auth/cloud-platform')
-    """The scopes required for authenticating as a BigQuery consumer."""

bigquery/google/cloud/bigquery/client.py

@@ -72,11 +72,14 @@ class Client(ClientWithProject):
                  ``credentials`` for the current object.
     """
 
+    SCOPE = ('https://www.googleapis.com/auth/bigquery',
+             'https://www.googleapis.com/auth/cloud-platform')
+    """The scopes required for authenticating as a BigQuery consumer."""
+
     def __init__(self, project=None, credentials=None, http=None):
         super(Client, self).__init__(
             project=project, credentials=credentials, http=http)
-        self._connection = Connection(
-            credentials=self._credentials, http=self._http)
+        self._connection = Connection(self)
 
     def list_projects(self, max_results=None, page_token=None):
         """List projects for the project associated with this client.

bigquery/unit_tests/test__http.py

@@ -27,7 +27,7 @@ def _make_one(self, *args, **kw):
         return self._get_target_class()(*args, **kw)
 
     def test_build_api_url_no_extra_query_params(self):
-        conn = self._make_one()
+        conn = self._make_one(object())
         URI = '/'.join([
             conn.API_BASE_URL,
             'bigquery',
@@ -40,7 +40,7 @@ def test_build_api_url_w_extra_query_params(self):
         from six.moves.urllib.parse import parse_qsl
         from six.moves.urllib.parse import urlsplit
 
-        conn = self._make_one()
+        conn = self._make_one(object())
         uri = conn.build_api_url('/foo', {'bar': 'baz'})
         scheme, netloc, path, qs, _ = urlsplit(uri)
         self.assertEqual('%s://%s' % (scheme, netloc), conn.API_BASE_URL)

core/google/cloud/_http.py

@@ -19,10 +19,6 @@
 import six
 from six.moves.urllib.parse import urlencode
 
-import google.auth.credentials
-import google_auth_httplib2
-import httplib2
-
 from google.cloud.exceptions import make_exception
 
 
@@ -37,50 +33,14 @@
 class Connection(object):
     """A generic connection to Google Cloud Platform.
 
-    Subclasses should understand only the basic types in method arguments,
-    however they should be capable of returning advanced types.
-
-    If no value is passed in for ``http``, a :class:`httplib2.Http` object
-    will be created and authorized with the ``credentials``. If not, the
-    ``credentials`` and ``http`` need not be related.
-
-    Subclasses may seek to use the private key from ``credentials`` to sign
-    data.
-
-    A custom (non-``httplib2``) HTTP object must have a ``request`` method
-    which accepts the following arguments:
-
-    * ``uri``
-    * ``method``
-    * ``body``
-    * ``headers``
-
-    In addition, ``redirections`` and ``connection_type`` may be used.
-
-    Without the use of ``credentials.authorize(http)``, a custom ``http``
-    object will also need to be able to add a bearer token to API
-    requests and handle token refresh on 401 errors.
-
-    :type credentials: :class:`google.auth.credentials.Credentials` or
-                       :class:`NoneType`
-    :param credentials: The credentials to use for this connection.
-
-    :type http: :class:`httplib2.Http` or class that defines ``request()``.
-    :param http: An optional HTTP object to make requests.
+    :type client: :class:`~google.cloud.client.Client`
+    :param client: The client that owns the current connection.
     """
 
     USER_AGENT = DEFAULT_USER_AGENT
 
-    SCOPE = None
-    """The scopes required for authenticating with a service.
-
-    Needs to be set by subclasses.
-    """
-
-    def __init__(self, credentials=None, http=None):
-        self._http = http
-        self._credentials = google.auth.credentials.with_scopes_if_required(
-            credentials, self.SCOPE)
+    def __init__(self, client):
+        self._client = client
 
     @property
     def credentials(self):
@@ -90,7 +50,7 @@ def credentials(self):
                 :class:`NoneType`
         :returns: The credentials object associated with this connection.
         """
-        return self._credentials
+        return self._client._credentials
 
     @property
     def http(self):
@@ -99,13 +59,7 @@ def http(self):
         :rtype: :class:`httplib2.Http`
         :returns: A Http object used to transport data.
         """
-        if self._http is None:
-            if self._credentials:
-                self._http = google_auth_httplib2.AuthorizedHttp(
-                    self._credentials)
-            else:
-                self._http = httplib2.Http()
-        return self._http
+        return self._client._http
 
 
 class JSONConnection(Connection):

core/google/cloud/client.py

@@ -16,6 +16,7 @@
 
 import google.auth.credentials
 from google.oauth2 import service_account
+import google_auth_httplib2
 import six
 
 from google.cloud._helpers import _determine_default_project
@@ -74,6 +75,26 @@ class Client(_ClientFactoryMixin):
     Stores ``credentials`` and ``http`` object so that subclasses
     can pass them along to a connection class.
 
+    If no value is passed in for ``http``, a :class:`httplib2.Http` object
+    will be created and authorized with the ``credentials``. If not, the
+    ``credentials`` and ``http`` need not be related.
+
+    Callers and subclasses may seek to use the private key from
+    ``credentials`` to sign data.
+
+    A custom (non-``httplib2``) HTTP object must have a ``request`` method
+    which accepts the following arguments:
+
+    * ``uri``
+    * ``method``
+    * ``body``
+    * ``headers``
+
+    In addition, ``redirections`` and ``connection_type`` may be used.
+
+    A custom ``http`` object will also need to be able to add a bearer token
+    to API requests and handle token refresh on 401 errors.
+
     :type credentials: :class:`~google.auth.credentials.Credentials`
     :param credentials: (Optional) The OAuth2 Credentials to use for this
                         client. If not passed (and if no ``http`` object is
@@ -88,15 +109,34 @@ class Client(_ClientFactoryMixin):
                  ``credentials`` for the current object.
     """
 
+    SCOPE = None
+    """The scopes required for authenticating with a service.
+
+    Needs to be set by subclasses.
+    """
+
     def __init__(self, credentials=None, http=None):
         if (credentials is not None and
                 not isinstance(
                     credentials, google.auth.credentials.Credentials)):
             raise ValueError(_GOOGLE_AUTH_CREDENTIALS_HELP)
         if credentials is None and http is None:
             credentials = get_credentials()
-        self._credentials = credentials
-        self._http = http
+        self._credentials = google.auth.credentials.with_scopes_if_required(
+            credentials, self.SCOPE)
+        self._http_internal = http
+
+    @property
+    def _http(self):
+        """Getter for object used for HTTP transport.
+
+        :rtype: :class:`~httplib2.Http`
+        :returns: An HTTP object.
+        """
+        if self._http_internal is None:
+            self._http_internal = google_auth_httplib2.AuthorizedHttp(
+                self._credentials)
+        return self._http_internal
 
 
 class _ClientProjectMixin(object):