feat: support for the advance() operation

src/quorum/model.py

@@ -2377,6 +2377,26 @@ def approve(self, model = None, type = None):
         # operation, this may be used for chaining operations
         return self
 
+    def advance(self, name, delta = 1):
+        store = self._get_store()
+        value = store.find_and_modify(
+            {
+                "_id" : self._id
+            },
+            {
+                "$inc" : {
+                    name : delta
+                }
+            },
+            new = True
+        )
+        value = value or store.find_one({
+            "_id" : self._id
+        })
+        _value = value[name]
+        setattr(self, name, _value)
+        return _value
+
     def reload(self, *args, **kwargs):
         is_new = self.is_new()
         if is_new: exceptions.OperationalError("Can't reload a new model entity")

src/quorum/test/model.py

@@ -136,6 +136,37 @@ def test_delete(self):
         result = mock.Person.count()
         self.assertEqual(result, 0)
 
+    @quorum.secured
+    def test_advance(self):
+        result = mock.Person.count()
+        self.assertEqual(result, 0)
+
+        person = mock.Person()
+        person.age = 1
+        person.name = "Name"
+        person.save()
+
+        result = mock.Person.count()
+        self.assertEqual(result, 1)
+
+        person.advance("age")
+        self.assertEqual(person.age, 2)
+
+        person = person.reload()
+        self.assertEqual(person.age, 2)
+
+        person.advance("age", delta = 2)
+        self.assertEqual(person.age, 4)
+
+        person = person.reload()
+        self.assertEqual(person.age, 4)
+
+        person.advance("age", delta = -2)
+        self.assertEqual(person.age, 2)
+
+        person = person.reload()
+        self.assertEqual(person.age, 2)
+
     @quorum.secured
     def test_validation(self):
         person = mock.Person()