remerge trunk (again). fix issues caused by changes to deserialization calls on controllers.

1 files changed, 90 insertions, 44 deletions

diff --git a/nova/wsgi.py b/nova/wsgi.py
index 1eb66d067..ba0819466 100644
--- a/nova/wsgi.py
+++ b/nova/wsgi.py
@@ -36,6 +36,7 @@ import webob.exc
 
 from paste import deploy
 
+from nova import exception
 from nova import flags
 from nova import log as logging
 from nova import utils
@@ -82,6 +83,35 @@ class Server(object):
                              log=WritableLogger(logger))
 
 
+class Request(webob.Request):
+
+    def best_match_content_type(self):
+        """
+        Determine the most acceptable content-type based on the
+        query extension then the Accept header
+        """
+
+        parts = self.path.rsplit(".", 1)
+
+        if len(parts) > 1:
+            format = parts[1]
+            if format in ["json", "xml"]:
+                return "application/{0}".format(parts[1])
+
+        ctypes = ["application/json", "application/xml"]
+        bm = self.accept.best_match(ctypes)
+
+        return bm or "application/json"
+
+    def get_content_type(self):
+        try:
+            ct = self.headers["Content-Type"]
+            assert ct in ("application/xml", "application/json")
+            return ct
+        except Exception:
+            raise webob.exc.HTTPBadRequest("Invalid content type")
+
+
 class Application(object):
     """Base WSGI application wrapper. Subclasses need to implement __call__."""
 
@@ -113,7 +143,7 @@ class Application(object):
     def __call__(self, environ, start_response):
         r"""Subclasses will probably want to implement __call__ like this:
 
-        @webob.dec.wsgify
+        @webob.dec.wsgify(RequestClass=Request)
         def __call__(self, req):
           # Any of the following objects work as responses:
 
@@ -199,7 +229,7 @@ class Middleware(Application):
         """Do whatever you'd like to the response."""
         return response
 
-    @webob.dec.wsgify
+    @webob.dec.wsgify(RequestClass=Request)
     def __call__(self, req):
         response = self.process_request(req)
         if response:
@@ -212,7 +242,7 @@ class Debug(Middleware):
     """Helper class that can be inserted into any WSGI application chain
     to get information about the request and response."""
 
-    @webob.dec.wsgify
+    @webob.dec.wsgify(RequestClass=Request)
     def __call__(self, req):
         print ("*" * 40) + " REQUEST ENVIRON"
         for key, value in req.environ.items():
@@ -276,7 +306,7 @@ class Router(object):
         self._router = routes.middleware.RoutesMiddleware(self._dispatch,
                                                           self.map)
 
-    @webob.dec.wsgify
+    @webob.dec.wsgify(RequestClass=Request)
     def __call__(self, req):
         """
         Route the incoming request to a controller based on self.map.
@@ -285,7 +315,7 @@ class Router(object):
         return self._router
 
     @staticmethod
-    @webob.dec.wsgify
+    @webob.dec.wsgify(RequestClass=Request)
     def _dispatch(req):
         """
         Called by self._router after matching the incoming request to a route
@@ -304,11 +334,11 @@ class Controller(object):
     WSGI app that reads routing information supplied by RoutesMiddleware
     and calls the requested action method upon itself.  All action methods
     must, in addition to their normal parameters, accept a 'req' argument
-    which is the incoming webob.Request.  They raise a webob.exc exception,
+    which is the incoming wsgi.Request.  They raise a webob.exc exception,
     or return a dict which will be serialized by requested content type.
     """
 
-    @webob.dec.wsgify
+    @webob.dec.wsgify(RequestClass=Request)
     def __call__(self, req):
         """
         Call the method specified in req.environ by RoutesMiddleware.
@@ -318,32 +348,45 @@ class Controller(object):
         method = getattr(self, action)
         del arg_dict['controller']
         del arg_dict['action']
+        if 'format' in arg_dict:
+            del arg_dict['format']
         arg_dict['req'] = req
         result = method(**arg_dict)
+
         if type(result) is dict:
-            return self._serialize(result, req)
+            content_type = req.best_match_content_type()
+            body = self._serialize(result, content_type)
+
+            response = webob.Response()
+            response.headers["Content-Type"] = content_type
+            response.body = body
+            return response
+
         else:
             return result
 
-    def _serialize(self, data, request):
+    def _serialize(self, data, content_type):
         """
-        Serialize the given dict to the response type requested in request.
+        Serialize the given dict to the provided content_type.
         Uses self._serialization_metadata if it exists, which is a dict mapping
         MIME types to information needed to serialize to that type.
         """
         _metadata = getattr(type(self), "_serialization_metadata", {})
-        serializer = Serializer(request.environ, _metadata)
-        return serializer.to_content_type(data)
+        serializer = Serializer(_metadata)
+        try:
+            return serializer.serialize(data, content_type)
+        except exception.InvalidContentType:
+            raise webob.exc.HTTPNotAcceptable()
 
-    def _deserialize(self, data, request):
+    def _deserialize(self, data, content_type):
         """
-        Deserialize the request body to the response type requested in request.
+        Deserialize the request body to the specefied content type.
         Uses self._serialization_metadata if it exists, which is a dict mapping
         MIME types to information needed to serialize to that type.
         """
         _metadata = getattr(type(self), "_serialization_metadata", {})
-        serializer = Serializer(request.environ, _metadata)
-        return serializer.deserialize(data)
+        serializer = Serializer(_metadata)
+        return serializer.deserialize(data, content_type)
 
 
 class Serializer(object):
@@ -351,50 +394,53 @@ class Serializer(object):
     Serializes and deserializes dictionaries to certain MIME types.
     """
 
-    def __init__(self, environ, metadata=None):
+    def __init__(self, metadata=None):
         """
         Create a serializer based on the given WSGI environment.
         'metadata' is an optional dict mapping MIME types to information
         needed to serialize a dictionary to that type.
         """
         self.metadata = metadata or {}
-        req = webob.Request.blank('', environ)
-        suffix = req.path_info.split('.')[-1].lower()
-        if suffix == 'json':
-            self.handler = self._to_json
-        elif suffix == 'xml':
-            self.handler = self._to_xml
-        elif 'application/json' in req.accept:
-            self.handler = self._to_json
-        elif 'application/xml' in req.accept:
-            self.handler = self._to_xml
-        else:
-            # This is the default
-            self.handler = self._to_json
 
-    def to_content_type(self, data):
-        """
-        Serialize a dictionary into a string.
+    def _get_serialize_handler(self, content_type):
+        handlers = {
+            "application/json": self._to_json,
+            "application/xml": self._to_xml,
+        }
 
-        The format of the string will be decided based on the Content Type
-        requested in self.environ: by Accept: header, or by URL suffix.
+        try:
+            return handlers[content_type]
+        except Exception:
+            raise exception.InvalidContentType()
+
+    def serialize(self, data, content_type):
+        """
+        Serialize a dictionary into a string of the specified content type.
         """
-        return self.handler(data)
+        return self._get_serialize_handler(content_type)(data)
 
-    def deserialize(self, datastring):
+    def deserialize(self, datastring, content_type):
         """
         Deserialize a string to a dictionary.
 
         The string must be in the format of a supported MIME type.
         """
-        datastring = datastring.strip()
+        return self.get_deserialize_handler(content_type)(datastring)
+
+    def get_deserialize_handler(self, content_type):
+        handlers = {
+            "application/json": self._from_json,
+            "application/xml": self._from_xml,
+        }
+
         try:
-            is_xml = (datastring[0] == '<')
-            if not is_xml:
-                return utils.loads(datastring)
-            return self._from_xml(datastring)
-        except:
-            return None
+            return handlers[content_type]
+        except Exception:
+            raise exception.InvalidContentType(_("Invalid content type %s"
+                                                 % content_type))
+
+    def _from_json(self, datastring):
+        return utils.loads(datastring)
 
     def _from_xml(self, datastring):
         xmldata = self.metadata.get('application/xml', {})