add default coerce to any Select2Field

flask_admin/_types.py

@@ -243,6 +243,10 @@ class T_FIELD_ARGS_VALIDATORS_ALLOW_BLANK(T_FIELD_ARGS_VALIDATORS):
     allow_blank: NotRequired[bool]
 
 
+class T_FIELD_ARGS_VALIDATORS_SELECTABLE(T_FIELD_ARGS_VALIDATORS_ALLOW_BLANK):
+    coerce: NotRequired[t.Callable[[t.Any], t.Any]]
+
+
 class T_FIELD_ARGS_VALIDATORS_FILES(T_FIELD_ARGS_VALIDATORS):
     base_path: NotRequired[str]
     allow_overwrite: NotRequired[bool]

flask_admin/contrib/peewee/view.py

@@ -26,6 +26,7 @@
 from flask_admin.model.form import InlineFormAdmin
 
 from ..._types import T_FIELD_ARGS_VALIDATORS_FILES
+from ..._types import T_FIELD_ARGS_VALIDATORS_SELECTABLE
 from ..._types import T_FILTER
 from ..._types import T_PEEWEE_MODEL
 from ..._types import T_WIDGET
@@ -338,7 +339,10 @@ def scaffold_form(self) -> type[Form]:
     def scaffold_list_form(
         self,
         widget: type[T_WIDGET] | None = None,
-        validators: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None,
+        validators: dict[
+            str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+        ]
+        | None = None,
     ) -> type[Form]:
         """
         Create form for the `index_view` using only the columns from

flask_admin/contrib/sqla/form.py

@@ -9,6 +9,8 @@
 from sqlalchemy import Boolean
 from sqlalchemy import Column
 from sqlalchemy.orm import ColumnProperty
+from sqlalchemy.sql.type_api import TypeEngine
+from sqlalchemy_utils import ChoiceType
 from wtforms import Field
 from wtforms import fields
 from wtforms import Form
@@ -36,6 +38,7 @@
 from ..._types import T_FIELD_ARGS_VALIDATORS
 from ..._types import T_FIELD_ARGS_VALIDATORS_ALLOW_BLANK
 from ..._types import T_FIELD_ARGS_VALIDATORS_FILES
+from ..._types import T_FIELD_ARGS_VALIDATORS_SELECTABLE
 from ..._types import T_INSTRUMENTED_ATTRIBUTE
 from ..._types import T_MODEL_VIEW
 from ..._types import T_ORM_MODEL
@@ -228,7 +231,7 @@ def convert(
         if isinstance(prop, FieldPlaceholder):
             return form.recreate_field(prop.field)
 
-        kwargs: T_FIELD_ARGS_VALIDATORS_ALLOW_BLANK = {"validators": [], "filters": []}
+        kwargs: T_FIELD_ARGS_VALIDATORS_SELECTABLE = {"validators": [], "filters": []}
 
         if field_args:
             kwargs.update(field_args)  # type: ignore[typeddict-item]
@@ -356,7 +359,11 @@ def convert(
             form_choices = getattr(self.view, "form_choices", None)
             if mapper.class_ == self.view.model and form_choices:
                 choices = form_choices.get(prop.key)
+
                 if choices:
+                    if "coerce" not in kwargs:
+                        kwargs["coerce"] = coerce_factory(column.type)
+
                     return form.Select2Field(  # type: ignore[misc]
                         choices=choices,
                         allow_blank=column.nullable,  # type: ignore[arg-type]
@@ -648,6 +655,18 @@ def avoid_empty_strings(value: t.Any) -> t.Any:
     return value if value else None
 
 
+def coerce_factory(type_: TypeEngine[t.Any]) -> t.Callable[[t.Any], t.Any]:
+    """
+    Return a function to coerce a column, for use by Select2Field.
+    :param type_: Column type
+    """
+
+    if isinstance(type_, ChoiceType):
+        return choice_type_coerce_factory(type_)
+    else:
+        return type_.python_type
+
+
 def choice_type_coerce_factory(type_: T_CHOICE_TYPE) -> t.Callable[[t.Any], t.Any]:
     """
     Return a function to coerce a ChoiceType column, for use by Select2Field.
@@ -692,7 +711,10 @@ def get_form(
     base_class: type[form.BaseForm] = form.BaseForm,
     only: t.Collection[str | T_INSTRUMENTED_ATTRIBUTE] | None = None,
     exclude: t.Collection[str | T_INSTRUMENTED_ATTRIBUTE] | None = None,
-    field_args: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None,
+    field_args: dict[
+        str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+    ]
+    | None = None,
     hidden_pk: bool = False,
     ignore_hidden: bool = True,
     extra_fields: dict[str | T_INSTRUMENTED_ATTRIBUTE, Field] | None = None,

flask_admin/contrib/sqla/view.py

@@ -39,6 +39,7 @@
 from ..._types import T_COLUMN
 from ..._types import T_COLUMN_LIST
 from ..._types import T_FIELD_ARGS_VALIDATORS_FILES
+from ..._types import T_FIELD_ARGS_VALIDATORS_SELECTABLE
 from ..._types import T_FILTER
 from ..._types import T_INSTRUMENTED_ATTRIBUTE
 from ..._types import T_SQLALCHEMY_COLUMN
@@ -892,7 +893,10 @@ def scaffold_form(self) -> type[Form]:
     def scaffold_list_form(
         self,
         widget: type[T_WIDGET] | None = None,
-        validators: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None,
+        validators: dict[
+            str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+        ]
+        | None = None,
     ) -> type[Form]:
         """
         Create form for the `index_view` using only the columns from

flask_admin/model/base.py

@@ -29,6 +29,7 @@
 from .._types import T_COLUMN_LIST
 from .._types import T_COLUMN_TYPE_FORMATTERS
 from .._types import T_FIELD_ARGS_VALIDATORS_FILES
+from .._types import T_FIELD_ARGS_VALIDATORS_SELECTABLE
 from .._types import T_FILTER
 from .._types import T_INSTRUMENTED_ATTRIBUTE
 from .._types import T_ORM_MODEL
@@ -656,7 +657,10 @@ class MyModelView(BaseModelView):
 
     """
 
-    form_args: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None
+    form_args: (
+        dict[str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE]
+        | None
+    ) = None
     """
         Dictionary of form field arguments. Refer to WTForms documentation for
         list of possible options.
@@ -1395,7 +1399,10 @@ def scaffold_form(self) -> type[Form]:
     def scaffold_list_form(
         self,
         widget: type[T_WIDGET] | None = None,
-        validators: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None,
+        validators: dict[
+            str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+        ]
+        | None = None,
     ) -> type[Form]:
         """
         Create form for the `index_view` using only the columns from

flask_admin/tests/sqla/test_form.py

@@ -4,8 +4,11 @@
 import pytest
 import wtforms
 from wtforms.fields.simple import StringField
+from wtforms.validators import NumberRange
 
+from flask_admin.contrib.sqla import ModelView
 from flask_admin.contrib.sqla.form import AdminModelConverter
+from flask_admin.tests.sqla.test_basic import create_models
 
 sqla_admin_model_converters = [
     method_name
@@ -52,3 +55,64 @@ class TestForm(wtforms.Form):
             pass
 
         assert field() == "<p>widget overridden</p>"
+
+
+@pytest.mark.parametrize(
+    "session_or_db, field_name",
+    [
+        pytest.param("session", "int_field", id="session"),
+        pytest.param("session", "float_field", id="session"),
+        pytest.param("db", "int_field", id="db"),
+        pytest.param("db", "float_field", id="db"),
+    ],
+)
+def test_coerce(app, db, admin, session_or_db, field_name):
+    with app.app_context():
+        Model1, Model2 = create_models(db)
+        db.session.add_all(
+            [
+                Model2("1", int_field=1),
+                Model2("2", int_field=2),
+            ]
+        )
+        db.session.commit()
+
+        class MyModelView(ModelView):
+            form_columns = ["int_field"]
+            form_choices = {"int_field": [("101", "101"), ("150", "150")]}
+            form_args = {
+                "int_field": {"validators": [NumberRange(min=100, max=199)]},
+            }
+
+        class MyModelView2(MyModelView):
+            form_args = {
+                "int_field": {
+                    "validators": [NumberRange(min=100, max=199)],
+                    "coerce": int,
+                },
+            }
+
+        param = db if session_or_db == "session" else db.session
+        # test column_list with a list of strings
+        view1 = MyModelView(Model2, param, name="My Model1")
+        view2 = MyModelView2(Model2, param, name="My Model1", endpoint="mymodelview2")
+        admin.add_view(view1)
+        admin.add_view(view2)
+
+        client = app.test_client()
+        rv = client.get("/admin/model2/new/")
+        data = rv.data.decode("utf-8")
+        assert 'value="101"' in data
+        assert ">101</option>" in data
+
+        rv = client.post(
+            "/admin/model2/new/", data={"int_field": "150"}, follow_redirects=True
+        )
+        data = rv.data.decode("utf-8")
+        assert "Record was successfully created" in data
+
+        rv = client.post(
+            "/admin/mymodelview2/new/", data={"int_field": "150"}, follow_redirects=True
+        )
+        data = rv.data.decode("utf-8")
+        assert "Record was successfully created" in data