feat: Use server side != for queries. (#950)

Author: sorced-jim

google/cloud/ndb/_datastore_query.py

@@ -56,6 +56,8 @@
     "<=": query_pb2.PropertyFilter.Operator.LESS_THAN_OR_EQUAL,
     ">": query_pb2.PropertyFilter.Operator.GREATER_THAN,
     ">=": query_pb2.PropertyFilter.Operator.GREATER_THAN_OR_EQUAL,
+    "!=": query_pb2.PropertyFilter.Operator.NOT_EQUAL,
+    "IN": query_pb2.PropertyFilter.Operator.IN,
 }
 
 _KEY_NOT_IN_CACHE = object()

google/cloud/ndb/query.py

@@ -604,8 +604,6 @@ class FilterNode(Node):
         The constructor for this type may not always return a
         :class:`FilterNode`. For example:
 
-        * The filter ``name != value`` is converted into
-          ``(name > value) OR (name < value)`` (a :class:`DisjunctionNode`)
         * The filter ``name in (value1, ..., valueN)`` is converted into
           ``(name = value1) OR ... OR (name = valueN)`` (also a
           :class:`DisjunctionNode`)
@@ -639,11 +637,6 @@ def __new__(cls, name, opsymbol, value):
         if isinstance(value, model.Key):
             value = value._key
 
-        if opsymbol == _NE_OP:
-            node1 = FilterNode(name, _LT_OP, value)
-            node2 = FilterNode(name, _GT_OP, value)
-            return DisjunctionNode(node1, node2)
-
         if opsymbol == _IN_OP:
             if not isinstance(value, (list, tuple, set, frozenset)):
                 raise TypeError(
@@ -704,17 +697,17 @@ def _to_filter(self, post=False):
                 representation of the filter.
 
         Raises:
-            NotImplementedError: If the ``opsymbol`` is ``!=`` or ``in``, since
+            NotImplementedError: If the ``opsymbol`` is ``in``, since
                 they should correspond to a composite filter. This should
                 never occur since the constructor will create ``OR`` nodes for
-                ``!=`` and ``in``
+                ``in``
         """
         # Avoid circular import in Python 2.7
         from google.cloud.ndb import _datastore_query
 
         if post:
             return None
-        if self._opsymbol in (_NE_OP, _IN_OP):
+        if self._opsymbol in (_IN_OP):
             raise NotImplementedError(
                 "Inequality filters are not single filter "
                 "expressions and therefore cannot be converted "

tests/unit/test_model.py

@@ -479,15 +479,12 @@ def test___eq__():
     def test___ne__():
         prop = model.Property("name", indexed=True)
         value = 7.0
-        expected = query_module.DisjunctionNode(
-            query_module.FilterNode("name", "<", value),
-            query_module.FilterNode("name", ">", value),
-        )
+        expected = query_module.FilterNode("name", "!=", value)
 
-        or_node_left = prop != value
-        assert or_node_left == expected
-        or_node_right = value != prop
-        assert or_node_right == expected
+        ne_node_left = prop != value
+        assert ne_node_left == expected
+        ne_node_right = value != prop
+        assert ne_node_right == expected
 
     @staticmethod
     def test___lt__():

tests/unit/test_query.py

@@ -656,11 +656,14 @@ def test_constructor_in_invalid_container():
 
     @staticmethod
     def test_constructor_ne():
-        or_node = query_module.FilterNode("a", "!=", 2.5)
+        ne_node = query_module.FilterNode("a", "!=", 2.5)
 
         filter_node1 = query_module.FilterNode("a", "<", 2.5)
         filter_node2 = query_module.FilterNode("a", ">", 2.5)
-        assert or_node == query_module.DisjunctionNode(filter_node1, filter_node2)
+        assert ne_node != query_module.DisjunctionNode(filter_node1, filter_node2)
+        assert ne_node._value == 2.5
+        assert ne_node._opsymbol == "!="
+        assert ne_node._name == "a"
 
     @staticmethod
     def test_pickling():
@@ -693,10 +696,15 @@ def test__to_filter_post():
         filter_node = query_module.FilterNode("speed", ">=", 88)
         assert filter_node._to_filter(post=True) is None
 
+    @staticmethod
+    def test__to_ne_filter_op():
+        filter_node = query_module.FilterNode("speed", "!=", 88)
+        assert filter_node._to_filter(post=True) is None
+
     @staticmethod
     def test__to_filter_bad_op():
         filter_node = query_module.FilterNode("speed", ">=", 88)
-        filter_node._opsymbol = "!="
+        filter_node._opsymbol = "in"
         with pytest.raises(NotImplementedError):
             filter_node._to_filter()