add exclude_parent_fields param and first test

ormar/models/helpers/__init__.py

@@ -8,6 +8,7 @@ from ormar.models.helpers.pydantic import (
     get_potential_fields,
     get_pydantic_base_orm_config,
     get_pydantic_field,
+    remove_excluded_parent_fields,
 )
 from ormar.models.helpers.relations import (
     alias_manager,
@@ -36,4 +37,5 @@ __all__ = [
     "sqlalchemy_columns_from_model_fields",
     "populate_choices_validators",
     "meta_field_not_set",
+    "remove_excluded_parent_fields",
 ]

ormar/models/helpers/models.py

@@ -54,6 +54,8 @@ def populate_default_options_values(
         new_model.Meta.abstract = False
     if not hasattr(new_model.Meta, "orders_by"):
         new_model.Meta.orders_by = []
+    if not hasattr(new_model.Meta, "exclude_parent_fields"):
+        new_model.Meta.exclude_parent_fields = []
 
     if any(
         is_field_an_forward_ref(field) for field in new_model.Meta.model_fields.values()

ormar/models/helpers/pydantic.py

@@ -117,3 +117,17 @@ def get_potential_fields(attrs: Dict) -> Dict:
         for k, v in attrs.items()
         if (lenient_issubclass(v, BaseField) or isinstance(v, BaseField))
     }
+
+
+def remove_excluded_parent_fields(model: Type["Model"]):
+    """
+    Removes pydantic fields that should be excluded from parent models
+
+    :param model:
+    :type model: Type["Model"]
+    """
+    excludes = {*model.Meta.exclude_parent_fields} - {*model.Meta.model_fields.keys()}
+    if excludes:
+        model.__fields__ = {
+            k: v for k, v in model.__fields__.items() if k not in excludes
+        }