--- a/wsgraph/web.py	Sun Dec 09 20:10:07 2012 -0800
+++ b/wsgraph/web.py	Mon Dec 10 07:54:10 2012 -0800
@@ -7,13 +7,14 @@
 import json
 from webob import Request, Response, exc
 
+# rank constants
 GRAPH = 0
 NODE = 1
 EDGE = 2
 
+# XXX stubbing hacks
 def JSONFormatter(**kwargs):
     return json.dumps(kwargs, sort_keys=True)
-
 def JSONGraphFormatter(graph):
     return json.dumps({'nodes': graph.nodes(),
                        'edges': graph.edges()},
@@ -22,15 +23,27 @@
 class Dispatcher(object):
 
     def __init__(self, graph,
-                 graph_formatters=None, # TODO
-                 node_formatters=None, # TODO
-                 edge_formatters=None, # TODO
+                 graph_formatters=None,
+                 node_formatters=None,
+                 edge_formatters=None,
                  require_auth=False):
         self.graph = graph
         self.require_auth = require_auth
-        self.formatters = {0: JSONGraphFormatter,
-                           1: JSONFormatter,
-                           2: JSONFormatter}
+
+        # use JSON formatter by default
+        if graph_formatters is None:
+            graph_formatters = {None: JSONGraphFormatter}
+         if node_formatters is None:
+            node_formatters = {None: JSONFormatter}
+         if edge_formatters is None:
+            edge_formatters = {None: JSONFormatter}
+
+        self.formatters = {GRAPH: graph_formatters,
+                           NODE: node_formatters,
+                           EDGE: edge_formatters}
+        for key, value in formatters.items():
+            # ensure default formatter
+            assert None in value
 
         self.methods = dict([(i, getattr(self, i))
                              for i in dir(self)
@@ -45,8 +58,12 @@
         return response(environ, start_response)
 
     @staticmethod
-    def path_segments(request):
-        import pdb; pdb.set_trace()
+    def path_segments(path):
+        """split a path into segments"""
+        segments = path.strip('/').split('/')
+        if segments == ['']:
+            segments = []
+        return segments
 
     # HTTP methods
 
@@ -69,7 +86,7 @@
 
         """
 
-        segments = self.path_segments(request)
+        segments = self.path_segments(request.path_info)
         if len(segments) not in (0,1,2):
             return exc.HTTPNotFound()