[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.

3 files changed, 10 insertions, 11 deletions

diff --git a/addons/portal/mail_message.py b/addons/portal/mail_message.py
index 36b06484e9e..a54b4f423c4 100644
--- a/addons/portal/mail_message.py
+++ b/addons/portal/mail_message.py
@@ -20,7 +20,8 @@
 ##############################################################################
 
 from openerp import SUPERUSER_ID
-from openerp.osv import osv, orm
+from openerp.osv import osv
+from openerp.exceptions import AccessError
 from openerp.tools.translate import _
 
 
@@ -56,8 +57,7 @@ class mail_message(osv.Model):
         if group_user_id not in [group.id for group in group_ids]:
             cr.execute('SELECT DISTINCT id FROM "%s" WHERE type = %%s AND subtype_id IS NULL AND id = ANY (%%s)' % (self._table), ('comment', ids,))
             if cr.fetchall():
-                raise orm.except_orm(_('Access Denied'),
-                        _('The requested operation cannot be completed due to security restrictions. Please contact your system administrator.\n\n(Document type: %s, Operation: %s)') % \
+                raise AccessError(_('The requested operation cannot be completed due to security restrictions. Please contact your system administrator.\n\n(Document type: %s, Operation: %s)') % \
                         (self._description, operation))
 
         return super(mail_message, self).check_access_rule(cr, uid, ids=ids, operation=operation, context=context)
diff --git a/addons/portal/tests/test_portal.py b/addons/portal/tests/test_portal.py
index 6a8242bf0cf..6e23ca3d50c 100644
--- a/addons/portal/tests/test_portal.py
+++ b/addons/portal/tests/test_portal.py
@@ -21,7 +21,6 @@
 
 from openerp.addons.mail.tests.common import TestMail
 from openerp.exceptions import AccessError
-from openerp.osv.orm import except_orm
 from openerp.tools.misc import mute_logger
 
 
@@ -60,7 +59,7 @@ class test_portal(TestMail):
 
         # Do: Chell browses Pigs -> ko, employee group
         chell_pigs = self.mail_group.browse(cr, self.user_chell_id, self.group_pigs_id)
-        with self.assertRaises(except_orm):
+        with self.assertRaises(AccessError):
             trigger_read = chell_pigs.name
 
         # Do: Chell posts a message on Pigs, crash because can not write on group or is not in the followers
@@ -77,7 +76,7 @@ class test_portal(TestMail):
             if partner.id == self.partner_chell_id:
                 # Chell can read her own partner record
                 continue
-            with self.assertRaises(except_orm):
+            with self.assertRaises(AccessError):
                 trigger_read = partner.name
 
         # Do: Chell comments Pigs, ok because he is now in the followers
@@ -99,7 +98,7 @@ class test_portal(TestMail):
         for message in chell_port.message_ids:
             trigger_read = message.subject
         for partner in chell_port.message_follower_ids:
-            with self.assertRaises(except_orm):
+            with self.assertRaises(AccessError):
                 trigger_read = partner.name
 
     def test_10_mail_invite(self):
@@ -225,5 +224,5 @@ class test_portal(TestMail):
         self.mail_message.read(cr, self.user_chell_id, msg_ids, ['body', 'type', 'subtype_id'])
 
         # Do: Chell read a message she should not be able to read
-        with self.assertRaises(except_orm):
+        with self.assertRaises(AccessError):
             self.mail_message.read(cr, self.user_chell_id, [msg4_id], ['body', 'type', 'subtype_id'])
diff --git a/addons/portal/wizard/portal_wizard.py b/addons/portal/wizard/portal_wizard.py
index 24158b41448..0571941b950 100644
--- a/addons/portal/wizard/portal_wizard.py
+++ b/addons/portal/wizard/portal_wizard.py
@@ -25,6 +25,7 @@ from openerp.osv import fields, osv
 from openerp.tools.translate import _
 from openerp.tools import email_split
 from openerp import SUPERUSER_ID
+from openerp.exceptions import UserError
 
 _logger = logging.getLogger(__name__)
 
@@ -160,7 +161,7 @@ class wizard_user(osv.osv_memory):
     def action_apply(self, cr, uid, ids, context=None):
         error_msg = self.get_error_messages(cr, uid, ids, context=context)
         if error_msg:
-            raise osv.except_osv(_('Contacts Error'), "\n\n".join(error_msg))
+            raise UserError( "\n\n".join(error_msg))
 
         for wizard_user in self.browse(cr, SUPERUSER_ID, ids, context):
             portal = wizard_user.wizard_id.portal_id
@@ -222,8 +223,7 @@ class wizard_user(osv.osv_memory):
         this_context = context
         this_user = self.pool.get('res.users').browse(cr, SUPERUSER_ID, uid, context)
         if not this_user.email:
-            raise osv.except_osv(_('Email Required'),
-                _('You must have an email address in your User Preferences to send emails.'))
+            raise UserError(_('You must have an email address in your User Preferences to send emails.'))
 
         # determine subject and body in the portal user's language
         user = self._retrieve_user(cr, SUPERUSER_ID, wizard_user, context)