Enabled use of BaseFilter instances on SQLA model views

flask_admin/contrib/sqla/view.py

@@ -17,7 +17,7 @@ from flask_admin.model.fields import ListEditableFieldList
 from flask_admin.actions import action
 from flask_admin._backwards import ObsoleteAttr
 
-from flask_admin.contrib.sqla import form, filters, tools
+from flask_admin.contrib.sqla import form, filters as sqla_filters, tools
 from .typefmt import DEFAULT_FORMATTERS
 from .tools import get_query_for_ids
 from .ajax import create_ajax_loader
@@ -154,7 +154,7 @@ class ModelView(BaseModelView):
                 inline_model_form_converter = MyInlineModelConverter
     """
 
-    filter_converter = filters.FilterConverter()
+    filter_converter = sqla_filters.FilterConverter()
     """
         Field to filter converter.
 
@@ -576,17 +576,8 @@ class ModelView(BaseModelView):
 
             return flt
 
-    def is_valid_filter(self, filter):
-        """
-            Verify that the provided filter object is derived from the
-            SQLAlchemy-compatible filter class.
-
-            :param filter:
-                Filter object to verify.
-        """
-        return isinstance(filter, filters.BaseSQLAFilter)
-
     def handle_filter(self, filter):
+        if isinstance(filter, sqla_filters.BaseSQLAFilter):
             column = filter.column
 
             if self._need_join(column.table):
@@ -810,6 +801,7 @@ class ModelView(BaseModelView):
                 flt = self._filters[idx]
 
                 # Figure out joins
+                if isinstance(flt, sqla_filters.BaseSQLAFilter):
                     tbl = flt.column.table.name
 
                     join_tables = self._filter_joins.get(tbl, [])