from zope.configuration.exceptions import ConfigurationError as ZCE
from zope.interface import implements
from repoze.bfg.decorator import reify
from repoze.bfg.interfaces import IExceptionResponse
import cgi
class ExceptionResponse(Exception):
""" Abstract class to support behaving as a WSGI response object """
implements(IExceptionResponse)
status = None
def __init__(self, message=''):
Exception.__init__(self, message) # B / C
self.message = message
@reify # defer execution until asked explicitly
def app_iter(self):
return [
"""
%s
%s
%s
""" % (self.status, self.status, cgi.escape(self.message))
]
@reify # defer execution until asked explicitly
def headerlist(self):
return [
('Content-Length', str(len(self.app_iter[0]))),
('Content-Type', 'text/html')
]
class Forbidden(ExceptionResponse):
"""
Raise this exception within :term:`view` code to immediately
return the :term:`forbidden view` to the invoking user. Usually
this is a basic ``401`` page, but the forbidden view can be
customized as necessary. See :ref:`changing_the_forbidden_view`.
This exception's constructor accepts a single positional argument,
which should be a string. The value of this string will be placed
into the WSGI environment by the router under the
``repoze.bfg.message`` key, for availability to the
:term:`Forbidden View`.
"""
status = '401 Unauthorized'
class NotFound(ExceptionResponse):
"""
Raise this exception within :term:`view` code to immediately
return the :term:`Not Found view` to the invoking user. Usually
this is a basic ``404`` page, but the Not Found view can be
customized as necessary. See :ref:`changing_the_notfound_view`.
This exception's constructor accepts a single positional argument,
which should be a string. The value of this string will be placed
into the WSGI environment by the router under the
``repoze.bfg.message`` key, for availability to the :term:`Not Found
View`.
"""
status = '404 Not Found'
class PredicateMismatch(NotFound):
"""
Internal exception (not an API) raised by multiviews when no
view matches. This exception subclasses the ``NotFound``
exception only one reason: if it reaches the main exception
handler, it should be treated like a ``NotFound`` by any exception
view registrations.
"""
class URLDecodeError(UnicodeDecodeError):
"""
This exception is raised when :mod:`repoze.bfg` cannot
successfully decode a URL or a URL path segment. This exception
it behaves just like the Python builtin
:exc:`UnicodeDecodeError`. It is a subclass of the builtin
:exc:`UnicodeDecodeError` exception only for identity purposes,
mostly so an exception view can be registered when a URL cannot be
decoded.
"""
class ConfigurationError(ZCE):
""" Raised when inappropriate input values are supplied to an API
method of a :term:`Configurator`"""