Method get_ordering

django/contrib/admin/views/main.py:375–422

Return the list of ordering fields for the change list. First check the get_ordering() method in model admin, then check the object's default ordering. Then, any manually-specified ordering from the query string overrides anything. Finally, a deterministic or

(self, request, queryset)

            return getattr(attr, "admin_order_field", None)

    def get_ordering(self, request, queryset):
        """
        Return the list of ordering fields for the change list.
        First check the get_ordering() method in model admin, then check
        the object's default ordering. Then, any manually-specified ordering
        from the query string overrides anything. Finally, a deterministic
        order is guaranteed by calling _get_deterministic_ordering() with the
        constructed ordering.
        """
        params = self.params
        ordering = list(
            self.model_admin.get_ordering(request) or self._get_default_ordering()
        )
        if params.get(ORDER_VAR):
            # Clear ordering and used params
            ordering = []
            order_params = params[ORDER_VAR].split(".")
            for p in order_params:
                try:
                    none, pfx, idx = p.rpartition("-")
                    field_name = self.list_display[int(idx)]
                    order_field = self.get_ordering_field(field_name)
                    if not order_field:
                        continue  # No 'admin_order_field', skip it
                    if isinstance(order_field, OrderBy):
                        if pfx == "-":
                            order_field = order_field.copy()
                            order_field.reverse_ordering()
                        ordering.append(order_field)
                    elif hasattr(order_field, "resolve_expression"):
                        # order_field is an expression.
                        ordering.append(
                            order_field.desc() if pfx == "-" else order_field.asc()
                        )
                    # reverse order if order_field has already "-" as prefix
                    elif pfx == "-" and order_field.startswith(pfx):
                        ordering.append(order_field.removeprefix(pfx))
                    else:
                        ordering.append(pfx + order_field)
                except (IndexError, ValueError):
                    continue  # Invalid ordering specified, skip it.

        # Add the given query's ordering fields, if any.
        ordering.extend(queryset.query.order_by)

        if queryset.order_by(*ordering).totally_ordered:
            return ordering
        return ordering + ["-pk"]

    def get_ordering_field_columns(self):
        """