--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cubicweb/web/_exceptions.py	Sat Jan 16 13:48:51 2016 +0100
@@ -0,0 +1,108 @@
+# pylint: disable=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 six.moves import http_client
+
+from cubicweb._exceptions import *
+from cubicweb.utils import json_dumps
+
+
+class DirectResponse(Exception):
+    """Used to supply a twitted HTTP Response directly"""
+    def __init__(self, response):
+        self.response = response
+
+class InvalidSession(CubicWebException):
+    """raised when a session id is found but associated session is not found or
+    invalid"""
+
+# Publish related exception
+
+class PublishException(CubicWebException):
+    """base class for publishing related exception"""
+
+    def __init__(self, *args, **kwargs):
+        self.status = kwargs.pop('status', http_client.OK)
+        super(PublishException, self).__init__(*args, **kwargs)
+
+class LogOut(PublishException):
+    """raised to ask for deauthentication of a logged in user"""
+    def __init__(self, url=None):
+        super(LogOut, self).__init__()
+        self.url = url
+
+class Redirect(PublishException):
+    """raised to redirect the http request"""
+    def __init__(self, location, status=http_client.SEE_OTHER):
+        super(Redirect, self).__init__(status=status)
+        self.location = location
+
+class StatusResponse(PublishException):
+
+    def __init__(self, status, content=''):
+        super(StatusResponse, self).__init__(status=status)
+        self.content = content
+
+    def __repr__(self):
+        return '%s(%r, %r)' % (self.__class__.__name__, self.status, self.content)
+
+# Publish related error
+
+class RequestError(PublishException):
+    """raised when a request can't be served because of a bad input"""
+
+    def __init__(self, *args, **kwargs):
+        kwargs.setdefault('status', http_client.BAD_REQUEST)
+        super(RequestError, self).__init__(*args, **kwargs)
+
+
+class NothingToEdit(RequestError):
+    """raised when an edit request doesn't specify any eid to edit"""
+
+    def __init__(self, *args, **kwargs):
+        kwargs.setdefault('status', http_client.BAD_REQUEST)
+        super(NothingToEdit, self).__init__(*args, **kwargs)
+
+class ProcessFormError(RequestError):
+    """raised when posted data can't be processed by the corresponding field
+    """
+    def __init__(self, *args, **kwargs):
+        kwargs.setdefault('status', http_client.BAD_REQUEST)
+        super(ProcessFormError, self).__init__(*args, **kwargs)
+
+class NotFound(RequestError):
+    """raised when something was not found. In most case,
+       a 404 error should be returned"""
+
+    def __init__(self, *args, **kwargs):
+        kwargs.setdefault('status', http_client.NOT_FOUND)
+        super(NotFound, self).__init__(*args, **kwargs)
+
+class RemoteCallFailed(RequestError):
+    """raised when a json remote call fails
+    """
+    def __init__(self, reason='', status=http_client.INTERNAL_SERVER_ERROR):
+        super(RemoteCallFailed, self).__init__(reason, status=status)
+        self.reason = reason
+
+    def dumps(self):
+        return json_dumps({'reason': self.reason})