Fix column_property in forms (#791)

sqladmin/forms.py

@@ -18,7 +18,12 @@
 import anyio
 from sqlalchemy import Boolean, select
 from sqlalchemy import inspect as sqlalchemy_inspect
-from sqlalchemy.orm import ColumnProperty, RelationshipProperty, sessionmaker
+from sqlalchemy.orm import (
+    ColumnProperty,
+    RelationshipProperty,
+    sessionmaker,
+)
+from sqlalchemy.sql.elements import Label
 from sqlalchemy.sql.schema import Column
 from wtforms import (
     BooleanField,
@@ -612,9 +617,12 @@ async def get_model_form(
     attributes = []
     names = only or mapper.attrs.keys()
     for name in names:
-        if exclude and name in exclude:
+        attr = mapper.attrs[name]
+        if (exclude and name in exclude) or (
+            isinstance(attr, ColumnProperty) and isinstance(attr.expression, Label)
+        ):
             continue
-        attributes.append((name, mapper.attrs[name]))
+        attributes.append((name, attr))
 
     field_dict = {}
     for name, attr in attributes:

tests/test_forms/test_forms.py

@@ -16,11 +16,14 @@
     Text,
     Time,
     TypeDecorator,
+    func,
+    select,
 )
 from sqlalchemy.dialects.postgresql import ARRAY, INET, MACADDR, UUID
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy.orm import (
     ColumnProperty,
+    column_property,
     composite,
     declarative_base,
     relationship,
@@ -333,3 +336,16 @@ class DataModel(Base):
     assert inspect.isfunction(Form.process)
     assert inspect.isfunction(Form.validate)
     assert inspect.isfunction(Form.populate_obj)
+
+
+async def test_column_property_is_ignored_in_form() -> None:
+    class Model(Base):
+        __tablename__ = "model_column_property"
+
+        id = Column(Integer, primary_key=True)
+        number = Column(Integer)
+        count = column_property(select(func.count("Model")).scalar_subquery())
+
+    Form = await get_model_form(model=Model, session_maker=session_maker)
+
+    assert "count" not in Form()._fields