- The ``__call__`` of a plugin "traverser" implementation (registered

  as an adapter for ``ITraverser`` or ``ITraverserFactory``) will now
  receive a *request* as the single argument to its ``__call__``
  method.  In previous versions it was passed a WSGI ``environ``
  object.  The request object passed to the factory implements
  dictionary-like methods in such a way that existing traverser code
  which expects to be passed an environ will continue to work.

- Fix docs.

10 files changed, 79 insertions, 47 deletions

diff --git a/CHANGES.txt b/CHANGES.txt
index ca6c501fb..b664ab092 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -22,6 +22,14 @@ Features
   factory code which expects to be passed an environ will continue to
   work.
 
+- The ``__call__`` of a plugin "traverser" implementation (registered
+  as an adapter for ``ITraverser`` or ``ITraverserFactory``) will now
+  receive a *request* as the single argument to its ``__call__``
+  method.  In previous versions it was passed a WSGI ``environ``
+  object.  The request object passed to the factory implements
+  dictionary-like methods in such a way that existing traverser code
+  which expects to be passed an environ will continue to work.
+
 Internal
 --------
 
diff --git a/docs/narr/hooks.rst b/docs/narr/hooks.rst
index d2020af0d..0fea7c64e 100644
--- a/docs/narr/hooks.rst
+++ b/docs/narr/hooks.rst
@@ -231,7 +231,7 @@ a class that implements the following interface:
        def __init__(self, root):
            """ Accept the root object returned from the root factory """
 
-       def __call__(self, environ):
+       def __call__(self, request):
            """ Return a dictionary with (at least) the keys ``root``,
            ``context``, ``view_name``, ``subpath``, ``traversed``,
            ``virtual_root``, and ``virtual_root_path``.  These values are
@@ -255,6 +255,16 @@ a class that implements the following interface:
            as attributes of the ``request`` object.
            """
 
+.. warning:: In :mod:`repoze.bfg.` 1.0 and previous versions, the
+     traverser ``__call__`` method accepted a WSGI *environment*
+     dictionary rather than a :term:`request` object.  The request
+     object passed to the traverser implements a dictionary-like API
+     which mutates and queries the environment, as a backwards
+     compatibility shim, in order to allow older code to work.
+     However, for maximum forward compatibility, traverser code
+     targeting :mod:`repoze.bfg` 1.1 and higher should expect a
+     request object directly.
+
 More than one traversal algorithm can be active at the same time.  For
 instance, if your :term:`root factory` returns more than one type of
 object conditionally, you could claim that an alternate traverser is
diff --git a/docs/narr/hybrid.rst b/docs/narr/hybrid.rst
index 34f606a97..4ff5df493 100644
--- a/docs/narr/hybrid.rst
+++ b/docs/narr/hybrid.rst
@@ -138,7 +138,7 @@ looks like so:
    root = Traversable(
            {'a':Traversable({'b':Traversable({'c':Traversable({})})})})
 
-   def root_factory(environ):
+   def root_factory(request):
        return root
 
 We've defined a bogus graph here that can be traversed, and a
diff --git a/docs/narr/router.rst b/docs/narr/router.rst
index 55df2936c..7382c07ae 100644
--- a/docs/narr/router.rst
+++ b/docs/narr/router.rst
@@ -21,18 +21,22 @@ processing?
    the WSGI environment to the ``__call__`` method of the
    :mod:`repoze.bfg` :term:`router` object.
 
+#. A :term:`request` object is created based on the WSGI environment.
+
 #. To service :term:`url dispatch`, the :mod:`repoze.bfg`
    :term:`router` calls a :term:`URL dispatch` "root factory wrapper"
    callable, which acts as a :term:`root factory`.  The job of the
-   mapper is to examine the ``PATH_INFO`` and other various keys in
-   the environment to determine whether any user-defined :term:`route`
-   matches the current WSGI environment.  The :term:`router` passes
-   the WSGI environment as an argument to the mapper.
+   mapper is to examine the ``PATH_INFO`` implied by the request to
+   determine whether any user-defined :term:`route` matches the
+   current WSGI environment.  The :term:`router` passes the request as
+   an argument to the mapper.
 
 #. If any route matches, the WSGI environment is mutated; a
    ``bfg.routes.route`` key and a ``bfg.routes.matchdict`` are added
-   to the WSGI environment.  If a route *doesn't* match, neither of
-   these keys is added to the WSGI environment.
+   to the WSGI environment, and an attribute named ``matchdict`` is
+   added to the request.  If a route *doesn't* match, neither of these
+   keys is added to the WSGI environment and the request object is not
+   mutated.
 
 #. Regardless of whether any route matched or not, the :term:`URL
    dispatch` mapper returns a root object.  If a particular
@@ -44,27 +48,17 @@ processing?
    ``make_app`` is ``None``, a default root factory is used to
    generate a root.
 
-#. A :term:`WebOb` :term:`request` is generated using the WSGI
-   environment.  The request type (its class and any :term:`interface`
-   attached to it) is dependent upon a combination of the
-   ``REQUEST_METHOD`` of the WSGI environment as well as any
-   :term:`route` match.  For example, a very particular kind of
-   request object is generated when the request has a
-   ``REQUEST_METHOD`` of ``POST`` and a :term:`route` named "home"
-   matches.  We use the request type to determine exactly which
-   :term:`view` to call later.
-
 #. A ``NewRequest`` :term:`event` is sent to any subscribers.
 
 #. The :mod:`repoze.bfg` router calls a "traverser" function with the
-   root object and the WSGI environment.  The traverser function
-   attempts to traverse the root object (using any existing
-   ``__getitem__`` on the root object and subobjects) to find a
-   :term:`context`.  If the root object has no ``__getitem__`` method,
-   the root itself is assumed to be the context.  The exact traversal
-   algorithm is described in :ref:`traversal_chapter`. The traverser
-   function returns a dictionary, which contains a :term:`context` and
-   a :term:`view name` as well as other ancillary information.
+   root object and the request.  The traverser function attempts to
+   traverse the root object (using any existing ``__getitem__`` on the
+   root object and subobjects) to find a :term:`context`.  If the root
+   object has no ``__getitem__`` method, the root itself is assumed to
+   be the context.  The exact traversal algorithm is described in
+   :ref:`traversal_chapter`. The traverser function returns a
+   dictionary, which contains a :term:`context` and a :term:`view
+   name` as well as other ancillary information.
 
 #. The request is decorated with various names returned from the
    traverser (such as ``context``, ``view_name``, and so forth), so
diff --git a/docs/narr/security.rst b/docs/narr/security.rst
index 90ead339c..773ab3a4f 100644
--- a/docs/narr/security.rst
+++ b/docs/narr/security.rst
@@ -522,7 +522,7 @@ An example of its usage, with all attributes fully expanded:
 
 The ``identifier_name`` controls the name used to look up the
 :term:`repoze.who` "identifier" plugin within
-``environ['repoze.who.plugins']`` which is used by this policy to
+``request.environ['repoze.who.plugins']`` which is used by this policy to
 "remember" and "forget" credentials.  It defaults to ``auth_tkt``.
 
 The ``callback`` is a Python dotted name to a function passed the
diff --git a/docs/narr/traversal.rst b/docs/narr/traversal.rst
index 340f8c277..5ed3db7cb 100644
--- a/docs/narr/traversal.rst
+++ b/docs/narr/traversal.rst
@@ -23,11 +23,10 @@ Users interact with your :mod:`repoze.bfg` -based application via a
 *router*, which is just a fancy :term:`WSGI` application.  At system
 startup time, the router is configured with a callback known as a
 :term:`root factory`, supplied by the application developer.  The root
-factory is passed the WSGI "environment" (a dictionary) and it is
-expected to return an object which represents the root of the model
-graph.  All :term:`traversal` will begin at this root object.  The
-root object is usually a *mapping* object (such as a Python
-dictionary).
+factory is passed a :term:`request` object and it is expected to
+return an object which represents the root of the model graph.  All
+:term:`traversal` will begin at this root object.  The root object is
+usually a *mapping* object (such as a Python dictionary).
 
 .. note:: If a :term:`root factory` is passed to the :mod:`repoze.bfg`
    "make_app" function as the value ``None``, a default root factory
@@ -43,6 +42,14 @@ dictionary).
    matched, it is also possible to do traversal *after* a route has
    been matched.  See :ref:`hybrid_chapter` for more information.
 
+.. warning:: In BFG 1.0 and prior versions, the root factory was
+    passed a term WSGI *environment* object (a dictionary) while in
+    BFG 1.1+ it is passed a request object.  For backwards
+    compatibility purposes, the request object passed to the root
+    factory has a dictionary-like interface that emulates the WSGI
+    environment, so code expecting the argument to be a dictionary
+    will continue to work.
+
 Items contained within the object graph are analogous to the concept
 of :term:`model` objects used by many other frameworks (and
 :mod:`repoze.bfg` refers to them as models, as well).  They are
@@ -93,10 +100,10 @@ code to execute:
 #.  The router creates a :term:`WebOb` request object based on the
     WSGI environment.
 
-#.  The :term:`root factory` is called with the WSGI environment.  It
+#.  The :term:`root factory` is called with the :term:`request`.  It
     returns a :term:`root` object.
 
-#.  The router uses the WSGI environment's ``PATH_INFO`` variable to
+#.  The router uses the request's ``PATH_INFO`` information to
     determine the path segments to traverse.  The leading slash is
     stripped off ``PATH_INFO``, and the remaining path segments are
     split on the slash character to form a traversal sequence, so a
diff --git a/docs/narr/urldispatch.rst b/docs/narr/urldispatch.rst
index 7a2a184f7..26d4b4a93 100644
--- a/docs/narr/urldispatch.rst
+++ b/docs/narr/urldispatch.rst
@@ -472,7 +472,7 @@ dispatch will by default be an instance of the object returned by the
 default :term:`root factory`.  You can override this behavior by
 passing in a ``factory`` argument to the ZCML directive for a
 particular route.  The ``factory`` should be a callable that accepts a
-WSGI environment and returns an instance of a class that will be the
+:term:`request` and returns an instance of a class that will be the
 context used by the view.
 
 An example of using a route with a factory:
@@ -489,7 +489,7 @@ An example of using a route with a factory:
 
 The above route will manufacture an ``Idea`` model as a context,
 assuming that ``mypackage.models.Idea`` resolves to a class that
-accepts a WSGI environment in its ``__init__``.
+accepts a request in its ``__init__``.
 
 .. note:: Values prefixed with a period (``.``) for the ``factory``
    and ``view`` attributes of a ``route`` (such as ``.models.Idea``
@@ -536,8 +536,8 @@ The ``.models`` module referred to above might look like so:
    :linenos:
 
    class Article(object):
-       def __init__(self, environ):
-           self.__dict__.update(environ['bfg.routes.matchdict'])
+       def __init__(self, request):
+           self.__dict__.update(request.matchdict)
 
        def is_root(self):
            return self.article == 'root'
@@ -739,8 +739,8 @@ Such a ``factory`` might look like so:
    :linenos:
 
    class Article(object):
-       def __init__(self, environ):
-          matchdict = environ['bfg.routes.matchdict']
+       def __init__(self, request):
+          matchdict = request.matchdict
           article = matchdict.get('article', None)
           if article == '1':
               self.__acl__ = [ (Allow, 'editor', 'view') ]
diff --git a/repoze/bfg/router.py b/repoze/bfg/router.py
index 3916d6627..c48a96664 100644
--- a/repoze/bfg/router.py
+++ b/repoze/bfg/router.py
@@ -71,7 +71,7 @@ class Router(object):
             traverser = registry.queryAdapter(root, ITraverser)
             if traverser is None:
                 traverser = ModelGraphTraverser(root)
-            tdict = traverser(environ)
+            tdict = traverser(request)
             context, view_name, subpath, traversed, vroot, vroot_path = (
                 tdict['context'], tdict['view_name'], tdict['subpath'],
                 tdict['traversed'], tdict['virtual_root'],
@@ -136,8 +136,8 @@ def make_app(root_factory, package=None, filename='configure.zcml',
     """ Return a Router object, representing a fully configured
     ``repoze.bfg`` WSGI application.
 
-    ``root_factory`` must be a callable that accepts a WSGI
-    environment and returns a traversal root object.  The traversal
+    ``root_factory`` must be a callable that accepts a :term:`request`
+    object and which returns a traversal root object.  The traversal
     root returned by the root factory is the *default* traversal root;
     it can be overridden on a per-view basis.  ``root_factory`` may be
     ``None``, in which case a 'default default' traversal root is
diff --git a/repoze/bfg/tests/test_router.py b/repoze/bfg/tests/test_router.py
index d2fbf4b2d..ac77508ef 100644
--- a/repoze/bfg/tests/test_router.py
+++ b/repoze/bfg/tests/test_router.py
@@ -46,7 +46,7 @@ class TestRouter(unittest.TestCase):
             def __init__(self, root):
                 self.root = root
 
-            def __call__(self, path):
+            def __call__(self, request):
                 values = {'root':self.root,
                           'context':context,
                           'view_name':view_name,
diff --git a/repoze/bfg/traversal.py b/repoze/bfg/traversal.py
index 43adcdebb..d48627e7e 100644
--- a/repoze/bfg/traversal.py
+++ b/repoze/bfg/traversal.py
@@ -268,12 +268,12 @@ def traverse(model, path):
     if path and path[0] == '/':
         model = find_root(model)
 
-    environ = {'PATH_INFO':path}
+    request = FakeRequest({'PATH_INFO':path})
     traverser = queryAdapter(model, ITraverser)
     if traverser is None:
         traverser = ModelGraphTraverser(model)
 
-    return traverser(environ)
+    return traverser(request)
 
 def model_path_tuple(model, *elements):
     """
@@ -474,7 +474,15 @@ class ModelGraphTraverser(object):
     def __init__(self, root):
         self.root = root
 
-    def __call__(self, environ):
+    def __call__(self, request):
+        try:
+            environ = request.environ
+        except AttributeError:
+            # In BFG 1.0 and before, this API expected an environ
+            # rather than a request; some bit of code may still be
+            # passing us an environ.  If so, deal.
+            environ = request
+
         if 'bfg.routes.matchdict' in environ:
             matchdict = environ['bfg.routes.matchdict']
 
@@ -623,3 +631,8 @@ class TraversalContextURL(object):
 def _join_path_tuple(tuple):
     return tuple and '/'.join([quote_path_segment(x) for x in tuple]) or '/'
 
+class FakeRequest(dict):
+    def __init__(self, environ):
+        self.update(environ)
+        self.environ = self # XXX circref?
+