Multi column sort with column_default_sort

Currently Flask-Admin doesn’t support sorting on multiple columns. Could you implement this?

column_default_sort = [(Model1.colA, True), ('colB', False)]

and

column_default_sort = [Model1.colA, 'colB']

[jbochi]

While #1590 is not merged, this will do the trick for sqla model views:

class ModelViewMultipleColSort(ModelView):
    def _get_default_order(self):
        order = self.column_default_sort
        if order:
            if isinstance(order, list):
                order = order
            elif isinstance(order, tuple):
                order = [order]
            else:
                order = [(order, False)]
        for field, direction in (order or []):
            attr, joins = tools.get_field_with_path(self.model, field)
            yield attr, joins, direction

    def _apply_sorting(self, query, joins, sort_column, sort_desc):
        if sort_column is not None:
            if sort_column in self._sortable_columns:
                sort_field = self._sortable_columns[sort_column]
                sort_joins = self._sortable_joins.get(sort_column)
                query, joins = self._order_by(query, joins, sort_joins,
                                              sort_field, sort_desc)
        else:
            order = list(self._get_default_order())
            for sort_field, sort_joins, sort_desc in order:
                query, joins = self._order_by(query, joins, sort_joins,
                                              sort_field, sort_desc)
        return query, joins

[theguywhodoesthething]

Thanks @jbochi. Formatting for those of you implementing this fix so you don’t get hung up for an hour like I did.

from flask_admin.contrib.sqla import tools 
column_default_sort = [[Company.name, False], [User.email_address, False]]