Merge pull request #550 from tseaver/514-rip_out_connection_cruft

#514: rip out `Connection` cruft

gcloud/datastore/api.py

@@ -19,8 +19,8 @@
 """
 
 from gcloud.datastore import _implicit_environ
-from gcloud.datastore.batch import _BATCHES
 from gcloud.datastore.batch import Batch
+from gcloud.datastore.transaction import Transaction
 from gcloud.datastore import helpers
 
 
@@ -113,10 +113,13 @@ def get(keys, missing=None, deferred=None, connection=None):
     connection = _require_connection(connection)
     dataset_id = _get_dataset_id_from_keys(keys)
 
+    transaction = Transaction.current()
+
     entity_pbs = connection.lookup(
         dataset_id=dataset_id,
         key_pbs=[k.to_protobuf() for k in keys],
         missing=missing, deferred=deferred,
+        transaction_id=transaction and transaction.id,
     )
 
     if missing is not None:
@@ -150,7 +153,7 @@ def put(entities, connection=None):
 
     connection = connection or _implicit_environ.CONNECTION
 
-    current = _BATCHES.top
+    current = Batch.current()
     in_batch = current is not None
     if not in_batch:
         keys = [entity.key for entity in entities]
@@ -177,7 +180,7 @@ def delete(keys, connection=None):
     connection = connection or _implicit_environ.CONNECTION
 
     # We allow partial keys to attempt a delete, the backend will fail.
-    current = _BATCHES.top
+    current = Batch.current()
     in_batch = current is not None
     if not in_batch:
         dataset_id = _get_dataset_id_from_keys(keys)

gcloud/datastore/batch.py

@@ -130,6 +130,11 @@ def __init__(self, dataset_id=None, connection=None):
         self._mutation = datastore_pb.Mutation()
         self._auto_id_entities = []
 
+    @staticmethod
+    def current():
+        """Return the topmost batch / transaction, or None."""
+        return _BATCHES.top
+
     @property
     def dataset_id(self):
         """Getter for dataset ID in which the batch will run.
@@ -308,6 +313,11 @@ def _assign_entity_to_mutation(mutation_pb, entity, auto_id_entities):
     insert.key.CopyFrom(key_pb)
 
     for name, value in entity.items():
+
+        value_is_list = isinstance(value, list)
+        if value_is_list and len(value) == 0:
+            continue
+
         prop = insert.property.add()
         # Set the name of the property.
         prop.name = name
@@ -316,7 +326,7 @@ def _assign_entity_to_mutation(mutation_pb, entity, auto_id_entities):
         helpers._set_protobuf_value(prop.value, value)
 
         if name in entity.exclude_from_indexes:
-            if not isinstance(value, list):
+            if not value_is_list:
                 prop.value.indexed = False
 
             for sub_value in prop.value.list_value: