web/_exceptions.py
author Alexandre Fayolle <alexandre.fayolle@logilab.fr>
Wed, 02 Jun 2010 16:12:18 +0000
branchstable
changeset 5639 4acb860159e4
parent 5426 0d4853a6e5ee
child 5940 0e3ae19b181a
permissions -rw-r--r--
[win32] fix deadlock occuring on the sequence tables with SQLServer actually, this deadlock would occur with any db backend other that PostgreSQL as the previous code was heavily relying on PG's SEQUENCE facility, not available elsewhere. Deadlock description: Thread1 starts creating entities (and therefore calls create_eid): -> this creates a DB-level lock on the entities_id_seq table, which will last until end of transaction Thread2 calls create_eid, which acquires the Python lock object, but updating the entities_id_seq is held by the DB lock Thread1 wants to create a new entity, calls create_eid, and is stuck by the Python lock object held by Thread2. Solution: use a separate connection to read and write the entities_id_seq table.

# pylint: disable-msg=W0401,W0614
# copyright 2003-2010 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
"""exceptions used in the core of the CubicWeb web application

"""
__docformat__ = "restructuredtext en"

from cubicweb._exceptions import *

class PublishException(CubicWebException):
    """base class for publishing related exception"""

class RequestError(PublishException):
    """raised when a request can't be served because of a bad input"""

class NothingToEdit(RequestError):
    """raised when an edit request doesn't specify any eid to edit"""

class ProcessFormError(RequestError):
    """raised when posted data can't be processed by the corresponding field
    """

class NotFound(RequestError):
    """raised when a 404 error should be returned"""

class Redirect(PublishException):
    """raised to redirect the http request"""
    def __init__(self, location):
        self.location = location

class DirectResponse(Exception):
    def __init__(self, response):
        self.response = response

class StatusResponse(Exception):
    def __init__(self, status, content=''):
        self.status = int(status)
        self.content = content

class InvalidSession(CubicWebException):
    """raised when a session id is found but associated session is not found or
    invalid
    """

class RemoteCallFailed(RequestError):
    """raised when a json remote call fails
    """
    def __init__(self, reason=''):
        super(RequestError, self).__init__()
        self.reason = reason

    def dumps(self):
        from cubicweb.web import json
        return json.dumps({'reason': self.reason})

class LogOut(PublishException):
    """raised to ask for deauthentication of a logged in user"""
    def __init__(self, url):
        super(LogOut, self).__init__()
        self.url = url