- The interface for ``repoze.bfg.interfaces.ITraverser`` and the

  built-in implementations that implement the interface
  (``repoze.bfg.traversal.ModelGraphTraverser``, and
  ``repoze.bfg.urldispatch.RoutesModelTraverser``) now expect the
  ``__call__`` method of an ITraverser to return 3 additional
  arguments: ``traversed``, ``virtual_root``, and
  ``virtual_root_path`` (the old contract was that the ``__call__``
  method of an ITraverser returned; three arguments, the contract new
  is that it returns six).  ``traversed`` will be a sequence of
  Unicode names that were traversed (including the virtual root path,
  if any) or ``None`` if no traversal was performed, ``virtual_root``
  will be a model object representing the virtual root (or the
  physical root if traversal was not performed), and
  ``virtual_root_path`` will be a sequence representing the virtual
  root path (a sequence of Unicode names) or ``None`` if traversal was
  not performed.

  Six arguments are now returned from BFG ITraversers.  They are
  returned in this order: ``context``, ``view_name``, ``subpath``,
  ``traversed``, ``virtual_root``, and ``virtual_root_path``.

  Places in the BFG code which called an ITraverser continue to accept
  a 3-argument return value, although BFG will generate and log a
  warning when one is encountered.

- The request object now has the following attributes: ``traversed``
  (the sequence of names traversed or ``None`` if traversal was not
  performed), ``virtual_root`` (the model object representing the
  virtual root, including the virtual root path if any), and
  ``virtual_root_path`` (the seuquence of names representing the
  virtual root path or ``None`` if traversal was not performed).

- A new decorator named ``wsgiapp2`` was added to the
  ``repoze.bfg.wsgi`` module.  This decorator performs the same
  function as ``repoze.bfg.wsgi.wsgiapp`` except it fixes up the
  ``SCRIPT_NAME``, and ``PATH_INFO`` environment values before
  invoking the WSGI subapplication.

- The ``repoze.bfg.testing.DummyRequest`` object now has default
  attributes for ``traversed``, ``virtual_root``, and
  ``virtual_root_path``.

- The RoutesModelTraverser now behaves more like the Routes
  "RoutesMiddleware" object when an element in the match dict is named
  ``path_info`` (usually when there's a pattern like
  ``http://foo/*path_info``).  When this is the case, the
  ``PATH_INFO`` environment variable is set to the value in the match
  dict, and the ``SCRIPT_NAME`` is appended to with the prefix of the
  original ``PATH_INFO`` not including the value of the new variable.

- The notfound debug now shows the traversed path, the virtual root,
  and the virtual root path too.

1 files changed, 28 insertions, 3 deletions

diff --git a/repoze/bfg/router.py b/repoze/bfg/router.py
index bc4a8cf7b..5278da892 100644
--- a/repoze/bfg/router.py
+++ b/repoze/bfg/router.py
@@ -72,6 +72,7 @@ class Router(object):
         self.logger = registry.queryUtility(ILogger, 'repoze.bfg.debug')
         self.root_factory = registry.getUtility(IRootFactory)
         self.root_policy = self.root_factory # b/w compat
+        self.traverser_warned = {}
 
     def __call__(self, environ, start_response):
         """
@@ -99,7 +100,24 @@ class Router(object):
             registry.has_listeners and registry.notify(NewRequest(request))
             root = self.root_factory(environ)
             traverser = registry.getAdapter(root, ITraverserFactory)
-            context, view_name, subpath = traverser(environ)
+            vals = traverser(environ)
+
+            try:
+                context, view_name, subpath, traversed, vroot, vroot_path = vals
+            except ValueError:
+                if not (traverser.__class__ in self.traverser_warned):
+                    self.logger and self.logger.warn(
+                        '%s is an pre-0.7.1-style ITraverser returning only '
+                        '3 arguments; please update it to the new '
+                        '6-argument-returning interface for improved '
+                        'functionality.  See the repoze.bfg.interfaces module '
+                        'for the new ITraverser interface '
+                        'definition' % traverser)
+                    self.traverser_warned[traverser.__class__] = True
+                context, view_name, subpath = vals
+                traversed = []
+                vroot = root
+                vroot_path = []
 
             if isinstance(request, WebObRequest):
                 # webob.Request's __setattr__ (as of 0.9.5 and lower)
@@ -111,11 +129,17 @@ class Router(object):
                 attrs['context'] = context
                 attrs['view_name'] = view_name
                 attrs['subpath'] = subpath
+                attrs['traversed'] = traversed
+                attrs['virtual_root'] = vroot
+                attrs['virtual_root_path'] = vroot_path
             else:
                 request.root = root
                 request.context = context
                 request.view_name = view_name
                 request.subpath = subpath
+                request.traversed = traversed
+                request.virtual_root = vroot
+                request.virtual_root_path = vroot_path
 
             security_policy = self.security_policy
 
@@ -156,9 +180,10 @@ class Router(object):
                 if self.debug_notfound:
                     msg = (
                         'debug_notfound of url %s; path_info: %r, context: %r, '
-                        'view_name: %r, subpath: %r' % (
+                        'view_name: %r, subpath: %r, traversed: %r, '
+                        'vroot: %r,  vroot_path: %r' % (
                         request.url, request.path_info, context, view_name,
-                        subpath)
+                        subpath, traversed, vroot, vroot_path)
                         )
                     logger and logger.debug(msg)
                 else: