Merge pull request #979 from tseaver/944-remove__implicit_environ

Remove '_implicit_environ'

Author: tseaver

gcloud/datastore/__init__.py

@@ -18,9 +18,10 @@
 
 >>> from gcloud import datastore
 
->>> key = datastore.Key('EntityKind', 1234)
+>>> client = datastore.Client()
+>>> key = client.key('EntityKind', 1234)
 >>> entity = datastore.Entity(key)
->>> query = datastore.Query(kind='EntityKind')
+>>> query = client.query(kind='EntityKind')
 
 The main concepts with this API are:
 
@@ -49,11 +50,6 @@
   when race conditions may occur.
 """
 
-from gcloud.datastore._implicit_environ import get_connection
-from gcloud.datastore._implicit_environ import get_default_connection
-from gcloud.datastore._implicit_environ import get_default_dataset_id
-from gcloud.datastore._implicit_environ import set_default_connection
-from gcloud.datastore._implicit_environ import set_default_dataset_id
 from gcloud.datastore.batch import Batch
 from gcloud.datastore.connection import SCOPE
 from gcloud.datastore.connection import Connection
@@ -62,25 +58,3 @@
 from gcloud.datastore.key import Key
 from gcloud.datastore.query import Query
 from gcloud.datastore.transaction import Transaction
-
-
-def set_defaults(dataset_id=None, connection=None):
-    """Set defaults either explicitly or implicitly as fall-back.
-
-    Uses the arguments to call the individual default methods
-
-    - set_default_dataset_id
-    - set_default_connection
-
-    In the future we will likely enable methods like
-
-    - set_default_namespace
-
-    :type dataset_id: string
-    :param dataset_id: Optional. The dataset ID to use as default.
-
-    :type connection: :class:`gcloud.datastore.connection.Connection`
-    :param connection: A connection provided to be the default.
-    """
-    set_default_dataset_id(dataset_id=dataset_id)
-    set_default_connection(connection=connection)

gcloud/datastore/_implicit_environ.py

@@ -13,20 +13,71 @@
 # limitations under the License.
 """Convenience wrapper for invoking APIs/factories w/ a dataset ID."""
 
+import os
+
 from gcloud._helpers import _LocalStack
+from gcloud._helpers import _app_engine_id
+from gcloud._helpers import _compute_engine_id
 from gcloud.datastore import helpers
+from gcloud.datastore.connection import Connection
 from gcloud.datastore.batch import Batch
 from gcloud.datastore.entity import Entity
 from gcloud.datastore.key import Key
 from gcloud.datastore.query import Query
 from gcloud.datastore.transaction import Transaction
-from gcloud.datastore._implicit_environ import _determine_default_dataset_id
-from gcloud.datastore._implicit_environ import get_connection
 
 
 _MAX_LOOPS = 128
 """Maximum number of iterations to wait for deferred keys."""
 
+_DATASET_ENV_VAR_NAME = 'GCLOUD_DATASET_ID'
+"""Environment variable defining default dataset ID."""
+
+_GCD_DATASET_ENV_VAR_NAME = 'DATASTORE_DATASET'
+"""Environment variable defining default dataset ID under GCD."""
+
+
+def _get_production_dataset_id():
+    """Gets the production application ID if it can be inferred."""
+    return os.getenv(_DATASET_ENV_VAR_NAME)
+
+
+def _get_gcd_dataset_id():
+    """Gets the GCD application ID if it can be inferred."""
+    return os.getenv(_GCD_DATASET_ENV_VAR_NAME)
+
+
+def _determine_default_dataset_id(dataset_id=None):
+    """Determine default dataset ID explicitly or implicitly as fall-back.
+
+    In implicit case, supports four environments. In order of precedence, the
+    implicit environments are:
+
+    * GCLOUD_DATASET_ID environment variable
+    * DATASTORE_DATASET environment variable (for ``gcd`` testing)
+    * Google App Engine application ID
+    * Google Compute Engine project ID (from metadata server)
+
+    :type dataset_id: string
+    :param dataset_id: Optional. The dataset ID to use as default.
+
+    :rtype: string or ``NoneType``
+    :returns: Default dataset ID if it can be determined.
+    """
+    if dataset_id is None:
+        dataset_id = _get_production_dataset_id()
+
+    if dataset_id is None:
+        dataset_id = _get_gcd_dataset_id()
+
+    if dataset_id is None:
+        dataset_id = _app_engine_id()
+
+    if dataset_id is None:
+        dataset_id = _compute_engine_id()
+
+    return dataset_id
+
 
 def _extended_lookup(connection, dataset_id, key_pbs,
                      missing=None, deferred=None,
@@ -126,7 +177,7 @@ def __init__(self, dataset_id=None, namespace=None, connection=None):
             raise EnvironmentError('Dataset ID could not be inferred.')
         self.dataset_id = dataset_id
         if connection is None:
-            connection = get_connection()
+            connection = Connection.from_environment()
         self.connection = connection
         self._batch_stack = _LocalStack()
         self.namespace = namespace

gcloud/datastore/_testing.py

@@ -17,7 +17,6 @@
 import copy
 import six
 
-from gcloud.datastore import _implicit_environ
 from gcloud.datastore import _datastore_v1_pb2 as datastore_pb
 
 
@@ -395,15 +394,11 @@ def _validate_dataset_id(dataset_id, parent):
     :rtype: string
     :returns: The ``dataset_id`` passed in, or implied from the environment.
     :raises: :class:`ValueError` if ``dataset_id`` is ``None`` and no dataset
-             can be inferred.
+             can be inferred from the parent.
     """
     if parent is None:
-
         if dataset_id is None:
-
-            dataset_id = _implicit_environ.get_default_dataset_id()
-            if dataset_id is None:
-                raise ValueError("A Key must have a dataset ID set.")
+            raise ValueError("A Key must have a dataset ID set.")
 
     return dataset_id
 

gcloud/datastore/client.py

@@ -102,7 +102,7 @@ def dataset_id(self):
 
         :rtype: str
         """
-        return self._dataset_id
+        return self._dataset_id or self._client.dataset_id
 
     @property
     def namespace(self):
@@ -111,7 +111,7 @@ def namespace(self):
         :rtype: string or None
         :returns: the namespace assigned to this query
         """
-        return self._namespace
+        return self._namespace or self._client.namespace
 
     @namespace.setter
     def namespace(self, value):