Merge pull request #1329 from dhermes/factor-out-_has_field

Moving _get_pb_property_value from bigtable into core.

Author: dhermes

gcloud/_helpers.py

@@ -388,6 +388,49 @@ def _datetime_to_pb_timestamp(when):
     return timestamp_pb2.Timestamp(seconds=seconds, nanos=nanos)
 
 
+def _has_field(message_pb, property_name):
+    """Determine if a field is set on a protobuf.
+
+    :type message_pb: :class:`google.protobuf.message.Message`
+    :param message_pb: The message to check for ``property_name``.
+
+    :type property_name: str
+    :param property_name: The property value to check against.
+
+    :rtype: bool
+    :returns: Flag indicating if ``property_name`` is set on ``message_pb``.
+    """
+    # NOTE: As of proto3, HasField() only works for message fields, not for
+    #       singular (non-message) fields. First try to use HasField and
+    #       if it fails (with a ValueError) we manually consult the fields.
+    try:
+        return message_pb.HasField(property_name)
+    except ValueError:
+        all_fields = set([field.name for field in message_pb._fields])
+        return property_name in all_fields
+
+
+def _get_pb_property_value(message_pb, property_name):
+    """Return a message field value.
+
+    :type message_pb: :class:`google.protobuf.message.Message`
+    :param message_pb: The message to check for ``property_name``.
+
+    :type property_name: str
+    :param property_name: The property value to check against.
+
+    :rtype: object
+    :returns: The value of ``property_name`` set on ``message_pb``.
+    :raises: :class:`ValueError <exceptions.ValueError>` if the result returned
+             from the ``message_pb`` does not contain the ``property_name``
+             value.
+    """
+    if _has_field(message_pb, property_name):
+        return getattr(message_pb, property_name)
+    else:
+        raise ValueError('Message does not contain %s.' % (property_name,))
+
+
 try:
     from pytz import UTC  # pylint: disable=unused-import,wrong-import-position
 except ImportError:

gcloud/bigtable/cluster.py

@@ -20,6 +20,7 @@
 from google.longrunning import operations_pb2
 
 from gcloud._helpers import _pb_timestamp_to_datetime
+from gcloud._helpers import _get_pb_property_value
 from gcloud.bigtable._generated import bigtable_cluster_data_pb2 as data_pb2
 from gcloud.bigtable._generated import (
     bigtable_cluster_service_messages_pb2 as messages_pb2)
@@ -47,30 +48,6 @@
 }
 
 
-def _get_pb_property_value(message_pb, property_name):
-    """Return a message field value.
-
-    :type message_pb: :class:`google.protobuf.message.Message`
-    :param message_pb: The message to check for ``property_name``.
-
-    :type property_name: str
-    :param property_name: The property value to check against.
-
-    :rtype: object
-    :returns: The value of ``property_name`` set on ``message_pb``.
-    :raises: :class:`ValueError <exceptions.ValueError>` if the result returned
-             from the ``message_pb`` does not contain the ``property_name``
-             value.
-    """
-    # Make sure `property_name` is set on the response.
-    # NOTE: As of proto3, HasField() only works for message fields, not for
-    #       singular (non-message) fields.
-    all_fields = set([field.name for field in message_pb._fields])
-    if property_name not in all_fields:
-        raise ValueError('Message does not contain %s.' % (property_name,))
-    return getattr(message_pb, property_name)
-
-
 def _prepare_create_request(cluster):
     """Creates a protobuf request for a CreateCluster request.
 

gcloud/bigtable/test_cluster.py

@@ -631,28 +631,6 @@ def test_list_tables_failure_name_bad_before(self):
             self._list_tables_helper(table_id, table_name=bad_table_name)
 
 
-class Test__get_pb_property_value(unittest2.TestCase):
-
-    def _callFUT(self, message_pb, property_name):
-        from gcloud.bigtable.cluster import _get_pb_property_value
-        return _get_pb_property_value(message_pb, property_name)
-
-    def test_it(self):
-        from gcloud.bigtable._generated import (
-            bigtable_cluster_data_pb2 as data_pb2)
-        serve_nodes = 119
-        cluster_pb = data_pb2.Cluster(serve_nodes=serve_nodes)
-        result = self._callFUT(cluster_pb, 'serve_nodes')
-        self.assertEqual(result, serve_nodes)
-
-    def test_with_value_unset_on_pb(self):
-        from gcloud.bigtable._generated import (
-            bigtable_cluster_data_pb2 as data_pb2)
-        cluster_pb = data_pb2.Cluster()
-        with self.assertRaises(ValueError):
-            self._callFUT(cluster_pb, 'serve_nodes')
-
-
 class Test__prepare_create_request(unittest2.TestCase):
 
     def _callFUT(self, cluster):

gcloud/datastore/connection.py

@@ -16,6 +16,7 @@
 
 import os
 
+from gcloud._helpers import _has_field
 from gcloud import connection
 from gcloud.environment_vars import GCD_HOST
 from gcloud.exceptions import make_exception
@@ -401,7 +402,7 @@ def _prepare_key_for_request(key_pb):  # pragma: NO COVER copied from helpers
     :returns: A key which will be added to a request. It will be the
               original if nothing needs to be changed.
     """
-    if key_pb.partition_id.HasField('dataset_id'):
+    if _has_field(key_pb.partition_id, 'dataset_id'):
         new_key_pb = _entity_pb2.Key()
         new_key_pb.CopyFrom(key_pb)
         new_key_pb.partition_id.ClearField('dataset_id')

gcloud/datastore/helpers.py

@@ -23,6 +23,7 @@
 import six
 
 from gcloud._helpers import _datetime_from_microseconds
+from gcloud._helpers import _has_field
 from gcloud._helpers import _microseconds_from_datetime
 from gcloud.datastore._generated import entity_pb2 as _entity_pb2
 from gcloud.datastore.entity import Entity
@@ -109,7 +110,7 @@ def _get_meaning(value_pb, is_list=False):
         if all_meanings:
             raise ValueError('Different meanings set on values '
                              'within a list_value')
-    elif value_pb.HasField('meaning'):
+    elif _has_field(value_pb, 'meaning'):
         meaning = value_pb.meaning
 
     return meaning
@@ -159,7 +160,7 @@ def entity_from_protobuf(pb):
     :returns: The entity derived from the protobuf.
     """
     key = None
-    if pb.HasField('key'):
+    if _has_field(pb, 'key'):
         key = key_from_protobuf(pb.key)
 
     entity_props = {}
@@ -259,18 +260,18 @@ def key_from_protobuf(pb):
     path_args = []
     for element in pb.path_element:
         path_args.append(element.kind)
-        if element.HasField('id'):
+        if _has_field(element, 'id'):
             path_args.append(element.id)
         # This is safe: we expect proto objects returned will only have
         # one of `name` or `id` set.
-        if element.HasField('name'):
+        if _has_field(element, 'name'):
             path_args.append(element.name)
 
     project = None
-    if pb.partition_id.HasField('dataset_id'):
+    if _has_field(pb.partition_id, 'dataset_id'):
         project = pb.partition_id.dataset_id
     namespace = None
-    if pb.partition_id.HasField('namespace'):
+    if _has_field(pb.partition_id, 'namespace'):
         namespace = pb.partition_id.namespace
 
     return Key(*path_args, namespace=namespace, project=project)
@@ -350,29 +351,29 @@ def _get_value_from_value_pb(value_pb):
     :returns: The value provided by the Protobuf.
     """
     result = None
-    if value_pb.HasField('timestamp_microseconds_value'):
+    if _has_field(value_pb, 'timestamp_microseconds_value'):
         microseconds = value_pb.timestamp_microseconds_value
         result = _datetime_from_microseconds(microseconds)
 
-    elif value_pb.HasField('key_value'):
+    elif _has_field(value_pb, 'key_value'):
         result = key_from_protobuf(value_pb.key_value)
 
-    elif value_pb.HasField('boolean_value'):
+    elif _has_field(value_pb, 'boolean_value'):
         result = value_pb.boolean_value
 
-    elif value_pb.HasField('double_value'):
+    elif _has_field(value_pb, 'double_value'):
         result = value_pb.double_value
 
-    elif value_pb.HasField('integer_value'):
+    elif _has_field(value_pb, 'integer_value'):
         result = value_pb.integer_value
 
-    elif value_pb.HasField('string_value'):
+    elif _has_field(value_pb, 'string_value'):
         result = value_pb.string_value
 
-    elif value_pb.HasField('blob_value'):
+    elif _has_field(value_pb, 'blob_value'):
         result = value_pb.blob_value
 
-    elif value_pb.HasField('entity_value'):
+    elif _has_field(value_pb, 'entity_value'):
         result = entity_from_protobuf(value_pb.entity_value)
 
     elif value_pb.list_value:
@@ -428,7 +429,7 @@ def _prepare_key_for_request(key_pb):
     :returns: A key which will be added to a request. It will be the
               original if nothing needs to be changed.
     """
-    if key_pb.partition_id.HasField('dataset_id'):
+    if _has_field(key_pb.partition_id, 'dataset_id'):
         # We remove the dataset_id from the protobuf. This is because
         # the backend fails a request if the key contains un-prefixed
         # project. The backend fails because requests to

gcloud/datastore/test_connection.py

@@ -900,7 +900,8 @@ def request(self, **kw):
 
 
 def _compare_key_pb_after_request(test, key_before, key_after):
-    test.assertFalse(key_after.partition_id.HasField('dataset_id'))
+    from gcloud._helpers import _has_field
+    test.assertFalse(_has_field(key_after.partition_id, 'dataset_id'))
     test.assertEqual(key_before.partition_id.namespace,
                      key_after.partition_id.namespace)
     test.assertEqual(len(key_before.path_element),

gcloud/datastore/test_helpers.py

@@ -198,6 +198,7 @@ def _callFUT(self, entity):
         return entity_to_protobuf(entity)
 
     def _compareEntityProto(self, entity_pb1, entity_pb2):
+        from gcloud._helpers import _has_field
         from gcloud.datastore.helpers import _property_tuples
 
         self.assertEqual(entity_pb1.key, entity_pb2.key)
@@ -208,7 +209,7 @@ def _compareEntityProto(self, entity_pb1, entity_pb2):
             name1, val1 = pair1
             name2, val2 = pair2
             self.assertEqual(name1, name2)
-            if val1.HasField('entity_value'):
+            if _has_field(val1, 'entity_value'):
                 self.assertEqual(val1.meaning, val2.meaning)
                 self._compareEntityProto(val1.entity_value,
                                          val2.entity_value)
@@ -767,6 +768,8 @@ def test_prefixed(self):
         self.assertEqual(PREFIXED, result)
 
     def test_unprefixed_bogus_key_miss(self):
+        from gcloud._helpers import _has_field
+
         UNPREFIXED = 'PROJECT'
         PREFIX = 's~'
         CONNECTION = _Connection(PREFIX, from_missing=False)
@@ -782,12 +785,14 @@ def test_unprefixed_bogus_key_miss(self):
         self.assertEqual(len(path_element), 1)
         self.assertEqual(path_element[0].kind, '__MissingLookupKind')
         self.assertEqual(path_element[0].id, 1)
-        self.assertFalse(path_element[0].HasField('name'))
+        self.assertFalse(_has_field(path_element[0], 'name'))
 
         PREFIXED = PREFIX + UNPREFIXED
         self.assertEqual(result, PREFIXED)
 
     def test_unprefixed_bogus_key_hit(self):
+        from gcloud._helpers import _has_field
+
         UNPREFIXED = 'PROJECT'
         PREFIX = 'e~'
         CONNECTION = _Connection(PREFIX, from_missing=True)
@@ -802,7 +807,7 @@ def test_unprefixed_bogus_key_hit(self):
         self.assertEqual(len(path_element), 1)
         self.assertEqual(path_element[0].kind, '__MissingLookupKind')
         self.assertEqual(path_element[0].id, 1)
-        self.assertFalse(path_element[0].HasField('name'))
+        self.assertFalse(_has_field(path_element[0], 'name'))
 
         PREFIXED = PREFIX + UNPREFIXED
         self.assertEqual(result, PREFIXED)

gcloud/datastore/test_key.py

@@ -333,7 +333,9 @@ def test_completed_key_on_complete(self):
         self.assertRaises(ValueError, key.completed_key, 5678)
 
     def test_to_protobuf_defaults(self):
+        from gcloud._helpers import _has_field
         from gcloud.datastore._generated import entity_pb2
+
         _KIND = 'KIND'
         key = self._makeOne(_KIND, project=self._DEFAULT_PROJECT)
         pb = key.to_protobuf()
@@ -342,15 +344,15 @@ def test_to_protobuf_defaults(self):
         # Check partition ID.
         self.assertEqual(pb.partition_id.dataset_id, self._DEFAULT_PROJECT)
         self.assertEqual(pb.partition_id.namespace, '')
-        self.assertFalse(pb.partition_id.HasField('namespace'))
+        self.assertFalse(_has_field(pb.partition_id, 'namespace'))
 
         # Check the element PB matches the partial key and kind.
         elem, = list(pb.path_element)
         self.assertEqual(elem.kind, _KIND)
         self.assertEqual(elem.name, '')
-        self.assertFalse(elem.HasField('name'))
+        self.assertFalse(_has_field(elem, 'name'))
         self.assertEqual(elem.id, 0)
-        self.assertFalse(elem.HasField('id'))
+        self.assertFalse(_has_field(elem, 'id'))
 
     def test_to_protobuf_w_explicit_project(self):
         _PROJECT = 'PROJECT-ALT'
@@ -381,12 +383,14 @@ def test_to_protobuf_w_explicit_path(self):
         self.assertEqual(elems[1].id, _ID)
 
     def test_to_protobuf_w_no_kind(self):
+        from gcloud._helpers import _has_field
+
         key = self._makeOne('KIND', project=self._DEFAULT_PROJECT)
         # Force the 'kind' to be unset. Maybe `to_protobuf` should fail
         # on this? The backend certainly will.
         key._path[-1].pop('kind')
         pb = key.to_protobuf()
-        self.assertFalse(pb.path_element[0].HasField('kind'))
+        self.assertFalse(_has_field(pb.path_element[0], 'kind'))
 
     def test_is_partial_no_name_or_id(self):
         key = self._makeOne('KIND', project=self._DEFAULT_PROJECT)