[IMP] Cleanup and refactoring of exception handling

Unify and refactor exception handling in framework and addons.

The generic `except_osv` is now deprecated, and replaced by more specialized exception subtypes:
 - `UserError` (renamed from Warning, as it conflicts with the built-in `Warning`) raised when a non-technical error occurs during a business operation. It could be a missing information in the data provided by the user, or a misconfiguration.
 - `AccessError`: raised when any operation is denied because the user conducting it does not have the required access rights.
 - `AccessDenied`: raised when an operation that requires authenticated access is attempted via an unauthenticated request.
 - `MissingError`: raised when an operation is attempted on a record that does not exist.
 - `ValidationError`: raised when an operation violates a SQL or Python constraint.
 - All other exceptions are internal errors due to a system problem or bug, and raised untouched to the client-side, which should display a traceback.

All exceptions take a single message argument.

The `test_exceptions` module has been updated to showcase both new and old (deprecated) exceptions.

A great many old `except_osv` had a useless title with "Error!" or "Warning", those have been removed, as this is handled by the client-side widget that displays the messages.

This commit introduces a more consistent policy for logging errors and warnings:
 - All messages that do not require administrator attention should be logged at INFO level or lower. This includes all errors that are notified to the user in a friendly manner, even for access right problems or validation errors during business operations.
 - All messages that indicate a likely misconfiguration or malicious use by the users should be logged at WARNING level, as they typically require administrator attention.
 - All other unhandled internal errors cannot typically be handled by the user and should be logged at ERROR or higher level, as they require immediate administrator attention.

1 files changed, 8 insertions, 9 deletions

diff --git a/addons/share/wizard/share_wizard.py b/addons/share/wizard/share_wizard.py
index f48ad7654e7..161cbfba112 100644
--- a/addons/share/wizard/share_wizard.py
+++ b/addons/share/wizard/share_wizard.py
@@ -33,6 +33,7 @@ from openerp.osv import expression
 from openerp.tools.translate import _
 from openerp.tools.safe_eval import safe_eval
 import openerp
+from openerp.exceptions import UserError
 _logger = logging.getLogger(__name__)
 
 FULL_ACCESS = ('perm_read', 'perm_write', 'perm_create', 'perm_unlink')
@@ -58,7 +59,7 @@ class share_wizard(osv.TransientModel):
            The error_message should have been translated with _().
         """
         if not condition:
-            raise osv.except_osv(_('Sharing access cannot be created.'), error_message)
+            raise UserError(error_message)
 
     def has_group(self, cr, uid, module, group_xml_id, context=None):
         """Returns True if current user is a member of the group identified by the module, group_xml_id pair."""
@@ -201,8 +202,7 @@ class share_wizard(osv.TransientModel):
     def go_step_1(self, cr, uid, ids, context=None):
         wizard_data = self.browse(cr,uid,ids,context)[0]
         if wizard_data.user_type == 'emails' and not self.has_email(cr, uid, context=context):
-            raise osv.except_osv(_('No email address configured'),
-                                 _('You must configure your email address in the user preferences before using the Share button.'))
+            raise UserError(_('You must configure your email address in the user preferences before using the Share button.'))
         model, res_id = self.pool.get('ir.model.data').get_object_reference(cr, uid, 'share', 'action_share_wizard_step1')
         action = self.pool[model].read(cr, uid, [res_id], context=context)[0]
         action['res_id'] = ids[0]
@@ -631,9 +631,8 @@ class share_wizard(osv.TransientModel):
                          group_id, model_id=model.id, domain=str(related_domain),
                          rule_name=rule_name, restrict=True, context=context)
         except Exception:
-            _logger.exception('Failed to create share access')
-            raise osv.except_osv(_('Sharing access cannot be created.'),
-                                 _('Sorry, the current screen and filter you are trying to share are not supported at the moment.\nYou may want to try a simpler filter.'))
+            _logger.info('Failed to create share access', exc_info=True)
+            raise UserError(_('Sorry, the current screen and filter you are trying to share are not supported at the moment.\nYou may want to try a simpler filter.'))
 
     def _check_preconditions(self, cr, uid, wizard_data, context=None):
         self._assert(wizard_data.action_id and wizard_data.access_mode,
@@ -755,7 +754,7 @@ class share_wizard(osv.TransientModel):
                     res_id = cond[2]
             # Record id not found: issue
             if res_id <= 0:
-                raise osv.except_osv(_('Record id not found'), _('The share engine has not been able to fetch a record_id for your invitation.'))
+                raise UserError(_('The share engine has not been able to fetch a record_id for your invitation.'))
             self.pool[model.model].message_subscribe(cr, uid, [res_id], new_ids + existing_ids, context=context)
             # self.send_invite_email(cr, uid, wizard_data, context=context)
             # self.send_invite_note(cr, uid, model.model, res_id, wizard_data, context=context)
@@ -810,7 +809,7 @@ class share_wizard(osv.TransientModel):
         notification_obj = self.pool.get('mail.notification')
         user = self.pool.get('res.users').browse(cr, UID_ROOT, uid)
         if not user.email:
-            raise osv.except_osv(_('Email Required'), _('The current user must have an email address configured in User Preferences to be able to send outgoing emails.'))
+            raise UserError(_('The current user must have an email address configured in User Preferences to be able to send outgoing emails.'))
         
         # TODO: also send an HTML version of this mail
         for result_line in wizard_data.result_line_ids:
@@ -841,7 +840,7 @@ class share_wizard(osv.TransientModel):
         mail_mail = self.pool.get('mail.mail')
         user = self.pool.get('res.users').browse(cr, UID_ROOT, uid)
         if not user.email:
-            raise osv.except_osv(_('Email Required'), _('The current user must have an email address configured in User Preferences to be able to send outgoing emails.'))
+            raise UserError(_('The current user must have an email address configured in User Preferences to be able to send outgoing emails.'))
         
         # TODO: also send an HTML version of this mail
         mail_ids = []