safe_eval is too restrictive and blocks all server actions with python code related to an osv.Model with deprecated columns

[Florent Aide]

In OpenERP v7 (trunk and 7.0) the res.partner core osv has deprecated the res_partner.country column.

This deprecation is interpreted in the orm.py which in turn uses _logger.warning:

            if field_column and field_column.deprecated:
                _logger.warning('Field %s.%s is deprecated: %s', self._name, f, field_column.deprecated)

_logger.warning tries to "import warnings" which fires an "from _warnings import ..." and gets blocked by safe_eval because at the moment:

_ALLOWED_MODULES = ['_strptime', 'time']

A quick and dirty way to solve the issue is to change the allowed modules list by adding '_warnings' to it

_ALLOWED_MODULES = ['_strptime', 'time', '_warnings']

Without this it is impossible to use server actions with python code on any osv object with a deprecated column (even if you don't manipulate this column in your server action). To go further as a side effect it is impossible to use python code for server actions on crm.lead because it fires orm requests on res.partner which in turn try to log a warning.

If the security implications are too high we should think to remove the deprecation warning mechanism from orm.py