- New public interface: ``repoze.bfg.exceptions.IExceptionResponse``.

  This interface is provided by all internal exception classes (such
  as ``repoze.bfg.exceptions.NotFound`` and
  ``repoze.bfg.exceptions.Forbidden``), instances of which are both
  exception objects and can behave as WSGI response objects.  This
  interface is made public so that exception classes which are also
  valid WSGI response factories can be configured to implement them
  or exception instances which are also or response instances can be
  configured to provide them.

- New API class: ``repoze.bfg.view.AppendSlashNotFoundViewFactory`` (undoes 
  previous custom_notfound_view on request passsed to 
  append_slash_notfound_view).

- Previously, two default view functions were registered at
  Configurator setup (one for ``repoze.bfg.exceptions.NotFound`` named
  ``default_notfound_view`` and one for
  ``repoze.bfg.exceptions.Forbidden`` named
  ``default_forbidden_view``) to render internal exception responses.
  Those default view functions have been removed, replaced with a
  generic default view function which is registered at Configurator
  setup for the ``repoze.bfg.interfaces.IExceptionResponse`` interface
  that simply returns the exception instance; the ``NotFound` and
  ``Forbidden`` classes are now still exception factories but they are
  also response factories which generate instances that implement the
  new ``repoze.bfg.interfaces.IExceptionResponse`` interface.

1 files changed, 50 insertions, 28 deletions

diff --git a/CHANGES.txt b/CHANGES.txt
index 65a08a781..351d284df 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -4,42 +4,48 @@ Next release
 Features
 --------
 
-- There can only be one Not Found view in any ``repoze.bfg``
-  application.  If you use
+- New public interface: ``repoze.bfg.exceptions.IExceptionResponse``.
+  This interface is provided by all internal exception classes (such
+  as ``repoze.bfg.exceptions.NotFound`` and
+  ``repoze.bfg.exceptions.Forbidden``), instances of which are both
+  exception objects and can behave as WSGI response objects.  This
+  interface is made public so that exception classes which are also
+  valid WSGI response factories can be configured to implement them
+  or exception instances which are also or response instances can be
+  configured to provide them.
+
+- New API class: ``repoze.bfg.view.AppendSlashNotFoundViewFactory``.
+
+  There can only be one Not Found view in any :mod:`repoze.bfg
+  application.  Even if you use
   ``repoze.bfg.view.append_slash_notfound_view`` as the Not Found
-  view, it still must generate a NotFound response when it cannot
-  redirect to a slash-appended URL; this not found response will be
-  visible to site users.
-
-  As of this release, if you wish to use a custom notfound view
-  callable when ``append_slash_notfound_view`` does not redirect to a
-  slash-appended URL, use a wrapper function as the
-  ``repoze.bfg.exceptions.NotFound`` view; have this wrapper attach a
-  view callable which returns a response to the request object named
-  ``custom_notfound_view`` before calling
-  ``append_slash_notfound_view``.  For example::
-
-       from webob.exc import HTTPNotFound
+  view, ``repoze.bfg`` still must generate a ``404 Not Found``
+  response when it cannot redirect to a slash-appended URL; this not
+  found response will be visible to site users.
+
+  If you don't care what this 404 response looks like, and you only
+  need redirections to slash-appended route URLs, you may use the
+  ``repoze.bfg.view.append_slash_notfound_view`` object as the Not
+  Found view.  However, if you wish to use a *custom* notfound view
+  callable when a URL cannot be redirected to a slash-appended URL,
+  you may wish to use an instance of the
+  ``repoze.bfg.view.AppendSlashNotFoundViewFactory`` class as the Not
+  Found view, supplying the notfound view callable as the first
+  argument to its constructor.  For instance::
+
        from repoze.bfg.exceptions import NotFound
-       from repoze.bfg.view import append_slash_notfound_view
+       from repoze.bfg.view import AppendSlashNotFoundViewFactory
 
-       def notfound_view(exc, request):
-           def fallback_notfound_view(exc, request):
-               return HTTPNotFound('It aint there, stop trying!')
-           request.fallback_notfound_view = fallback_notfound_view
-           return append_slash_notfound_view(exc, request)
+       def notfound_view(context, request):
+           return HTTPNotFound('It aint there, stop trying!')
 
-       config.add_view(notfound_view, context=NotFound)
+       custom_append_slash = AppendSlashNotFoundViewFactory(notfound_view)
+       config.add_view(custom_append_slash, context=NotFound)
 
-  ``custom_notfound_view`` must adhere to the two-argument view
+  The ``notfound_view`` supplied must adhere to the two-argument view
   callable calling convention of ``(context, request)`` (``context``
   will be the exception object).
 
-  If ``custom_notfound_view`` is not found on the request object, a
-  default notfound response will be generated when the
-  ``append_slash_notfound_view`` doesn't redirect to a slash-appended
-  URL.
-
 Documentation
 --------------
 
@@ -49,6 +55,22 @@ Documentation
 - Expanded the "Redirecting to Slash-Appended Routes" section of the
   URL Dispatch narrative chapter.
 
+Internal
+--------
+
+- Previously, two default view functions were registered at
+  Configurator setup (one for ``repoze.bfg.exceptions.NotFound`` named
+  ``default_notfound_view`` and one for
+  ``repoze.bfg.exceptions.Forbidden`` named
+  ``default_forbidden_view``) to render internal exception responses.
+  Those default view functions have been removed, replaced with a
+  generic default view function which is registered at Configurator
+  setup for the ``repoze.bfg.interfaces.IExceptionResponse`` interface
+  that simply returns the exception instance; the ``NotFound` and
+  ``Forbidden`` classes are now still exception factories but they are
+  also response factories which generate instances that implement the
+  new ``repoze.bfg.interfaces.IExceptionResponse`` interface.
+
 1.3a7 (2010-08-01)
 ==================