Merge pull request #714 from neo4j-contrib/fix/node-class-registry

Move Node class registry out of Database init

neomodel/core.py

@@ -681,20 +681,18 @@ def save(self):
 
         # create or update instance node
         if hasattr(self, "element_id"):
-            # TODO Get Neo4j version at creation time, and use method accordingly
-            # Node will now always have element_id, and deprecated id for users to call for a while
-            # Calling id now returns element_id value instead though
-            # For Neo4j version 5 : element_id=id=Neo elementId
-            # For Neo4j version 4 : element_id_id=Neo id
             # update
             params = self.deflate(self.__properties__, self)
-            query = f"""
-                MATCH (n) WHERE {db.get_id_method()}(n)=$self
-                SET 
-            """
-            query += ", ".join([f"n.{key} = ${key}" + "\n" for key in params.keys()])
-            for label in self.inherited_labels():
-                query += f"SET n:`{label}`\n"
+            query = f"MATCH (n) WHERE {db.get_id_method()}(n)=$self\n"
+
+            if params:
+                query += "SET "
+                query += ",\n".join([f"n.{key} = ${key}" for key in params])
+                query += "\n"
+            if self.inherited_labels():
+                query += "\n".join(
+                    [f"SET n:`{label}`" for label in self.inherited_labels()]
+                )
             self.cypher(query, params)
         elif hasattr(self, "deleted") and self.deleted:
             raise ValueError(

neomodel/util.py

@@ -62,8 +62,9 @@ class Database(local):
     A singleton object via which all operations from neomodel to the Neo4j backend are handled with.
     """
 
+    _NODE_CLASS_REGISTRY = {}
+
     def __init__(self):
-        self._NODE_CLASS_REGISTRY = {}
         self._active_transaction = None
         self.url = None
         self.driver = None

test/test_models.py

@@ -28,6 +28,10 @@ def email_alias(self, value):
         self.email = value
 
 
+class NodeWithoutProperty(StructuredNode):
+    pass
+
+
 def test_issue_233():
     class BaseIssue233(StructuredNode):
         __abstract_node__ = True
@@ -101,6 +105,12 @@ def test_save_to_model():
     assert u.age == 3
 
 
+def test_save_node_without_properties():
+    n = NodeWithoutProperty()
+    assert n.save()
+    assert n.element_id != ""
+
+
 def test_unique():
     install_labels(User)
     User(email="[email protected]", age=3).save()
@@ -231,6 +241,7 @@ def credit_account(self, amount):
     assert len(jim.labels()) == 1
     assert jim.labels()[0] == "Shopper"
 
+
 def test_inherited_optional_labels():
     class BaseOptional(StructuredNode):
         __optional_labels__ = ["Alive"]
@@ -244,16 +255,17 @@ def credit_account(self, amount):
             self.balance = self.balance + int(amount)
             self.save()
 
-    henry = ExtendedOptional(name='henry', balance=300).save()
+    henry = ExtendedOptional(name="henry", balance=300).save()
     henry.credit_account(50)
 
-    assert ExtendedOptional.__label__ == 'ExtendedOptional'
+    assert ExtendedOptional.__label__ == "ExtendedOptional"
     assert henry.balance == 350
     assert len(henry.inherited_labels()) == 2
     assert len(henry.labels()) == 2
 
     assert set(henry.inherited_optional_labels()) == {"Alive", "RewardsMember"}
 
+
 def test_mixins():
     class UserMixin:
         name = StringProperty(unique_index=True)