Merge pull request #10 from alvarolopez/refactor_rendering

Refactor rendering

ooi/api/base.py

@@ -14,7 +14,9 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-from ooi.wsgi import utils
+from ooi import utils
+
+import webob.exc
 
 
 class Controller(object):
@@ -31,3 +33,53 @@ def _get_req(self, req, path=None, content_type=None, body=None):
         if body is not None:
             req.body = utils.utf8(body)
         return req
+
+    @staticmethod
+    def get_from_response(response, element, default):
+        """Get a JSON element from a valid response or raise an exception.
+
+        This method will extract an element a JSON response (falling back to a
+        default value) if the response has a code of 200, otherwise it will
+        raise a webob.exc.exception
+
+        :param response: The webob.Response object
+        :param element: The element to look for in the JSON body
+        :param default: The default element to be returned if not found.
+        """
+        if response.status_int == 200:
+            return response.json_body.get(element, default)
+        else:
+            raise exception_from_response(response)
+
+
+def exception_from_response(response):
+    """Convert an OpenStack V2 Fault into a webob exception.
+
+    Since we are calling the OpenStack API we should process the Faults
+    produced by them. Extract the Fault information according to [1] and
+    convert it back to a webob exception.
+
+    [1] http://docs.openstack.org/developer/nova/v2/faults.html
+
+    :param response: a webob.Response containing an exception
+    :returns: a webob.exc.exception object
+    """
+    exceptions = {
+        400: webob.exc.HTTPBadRequest,
+        401: webob.exc.HTTPUnauthorized,
+        403: webob.exc.HTTPForbidden,
+        404: webob.exc.HTTPNotFound,
+        405: webob.exc.HTTPMethodNotAllowed,
+        406: webob.exc.HTTPNotAcceptable,
+        409: webob.exc.HTTPConflict,
+        413: webob.exc.HTTPRequestEntityTooLarge,
+        415: webob.exc.HTTPUnsupportedMediaType,
+        429: webob.exc.HTTPTooManyRequests,
+        501: webob.exc.HTTPNotImplemented,
+        503: webob.exc.HTTPServiceUnavailable,
+    }
+    code = response.status_int
+    message = response.json_body.popitem()[1].get("message")
+
+    exc = exceptions.get(code, webob.exc.HTTPInternalServerError)
+    return exc(explanation=message)

ooi/api/compute.py

@@ -38,7 +38,7 @@ def index(self, req):
         tenant_id = req.environ["keystone.token_auth"].user.project_id
         req = self._get_req(req, path="/%s/servers" % tenant_id)
         response = req.get_response(self.app)
-        servers = response.json_body.get("servers", [])
+        servers = self.get_from_response(response, "servers", [])
         occi_compute_resources = self._get_compute_resources(servers)
 
         return collection.Collection(resources=occi_compute_resources)
@@ -63,7 +63,7 @@ def create(self, req, headers, params, body):
                                 }}))
         response = req.get_response(self.app)
         # We only get one server
-        server = response.json_body.get("server", {})
+        server = self.get_from_response(response, "server", {})
 
         # The returned JSON does not contain the server name
         server["name"] = params["/occi/infrastructure"]
@@ -77,13 +77,13 @@ def show(self, id, req):
         # get info from server
         req = self._get_req(req, path="/%s/servers/%s" % (tenant_id, id))
         response = req.get_response(self.app)
-        s = response.json_body.get("server", {})
+        s = self.get_from_response(response, "server", {})
 
         # get info from flavor
         req = self._get_req(req, path="/%s/flavors/%s" % (tenant_id,
                                                           s["flavor"]["id"]))
         response = req.get_response(self.app)
-        flavor = response.json_body.get("flavor", {})
+        flavor = self.get_from_response(response, "flavor", {})
         res_tpl = templates.OpenStackResourceTemplate(flavor["name"],
                                                       flavor["vcpus"],
                                                       flavor["ram"],
@@ -93,7 +93,7 @@ def show(self, id, req):
         req = self._get_req(req, path="/%s/images/%s" % (tenant_id,
                                                          s["image"]["id"]))
         response = req.get_response(self.app)
-        image = response.json_body.get("image", {})
+        image = self.get_from_response(response, "image", {})
         os_tpl = templates.OpenStackOSTemplate(image["id"],
                                                image["name"])
 

ooi/api/query.py

@@ -29,7 +29,7 @@ def _resource_tpls(self, req):
         tenant_id = req.environ["keystone.token_auth"].user.project_id
         req = self._get_req(req, path="/%s/flavors/detail" % tenant_id)
         response = req.get_response(self.app)
-        flavors = response.json_body.get("flavors", [])
+        flavors = self.get_from_response(response, "flavors", [])
         occi_resource_templates = []
         if flavors:
             for f in flavors:
@@ -44,7 +44,7 @@ def _os_tpls(self, req):
         tenant_id = req.environ["keystone.token_auth"].user.project_id
         req = self._get_req(req, path="/%s/images/detail" % tenant_id)
         response = req.get_response(self.app)
-        images = response.json_body.get("images", [])
+        images = self.get_from_response(response, "images", [])
         occi_os_templates = []
         if images:
             for i in images:

ooi/occi/core/action.py

@@ -24,5 +24,10 @@ class Action(category.Category):
     instance.
     """
 
+    def __init__(self, scheme, term, title, attributes=None, location=None):
+        super(Action, self).__init__(scheme, term, title,
+                                     attributes=attributes,
+                                     location="?action=%s" % term)
+
     def _class_name(self):
         return "action"

ooi/occi/core/attribute.py

@@ -35,24 +35,6 @@ def name(self):
     def value(self):
         return self._value
 
-    def _as_str(self):
-        value_str = ''
-        if isinstance(self._value, six.string_types):
-            value_str = '"%s"' % self._value
-        elif isinstance(self._value, bool):
-            value_str = '"%s"' % str(self._value).lower()
-        else:
-            value_str = "%s" % self._value
-        return "%s=%s" % (self.name, value_str)
-
-    def __str__(self):
-        """Render the attribute to text/plain."""
-        return ": ".join(self.headers()[0])
-
-    def headers(self):
-        """Render the attribute to text/occi."""
-        return [("X-OCCI-Attribute", self._as_str())]
-
 
 class MutableAttribute(Attribute):
     @Attribute.value.setter

ooi/occi/core/category.py

@@ -15,6 +15,7 @@
 # under the License.
 
 from ooi.occi.core import attribute
+from ooi import utils
 
 
 class Category(object):
@@ -37,17 +38,10 @@ def _class_name(self):
         """Returns this class name (see OCCI v1.1 rendering)."""
         raise ValueError
 
-    def _as_str(self):
-        d = {
-            "term": self.term,
-            "scheme": self.scheme,
-            "class": self._class_name()
-        }
+    @property
+    def occi_class(self):
+        return self._class_name()
 
-        return '%(term)s; scheme="%(scheme)s"; class="%(class)s"' % d
-
-    def headers(self):
-        return [("Category", self._as_str())]
-
-    def __str__(self):
-        return ": ".join(self.headers()[0])
+    @property
+    def type_id(self):
+        return utils.join_url(self.scheme, "#%s" % self.term)

ooi/occi/core/collection.py

@@ -30,27 +30,3 @@ def __init__(self, kinds=[], mixins=[], actions=[],
         self.actions = actions
         self.resources = resources
         self.links = links
-
-    def __str__(self):
-        """Render the collection to text/plain."""
-        # NOTE(aloga): This is unfinished, we need to check what is inside the
-        # collection and render it properly. For example, if we have a
-        # collection of resources, we should render  only their locations.
-        ret = []
-        for what in [self.kinds, self.mixins, self.actions,
-                     self.resources, self.links]:
-            for el in what:
-                ret.append("X-OCCI-Location: %s" % el.location)
-        return "\n".join(ret)
-
-    def headers(self):
-        """Render the collection to text/occi."""
-        # NOTE(aloga): This is unfinished, we need to check what is inside the
-        # collection and render it properly. For example, if we have a
-        # collection of resources, we should render  only their locations.
-        headers = []
-        for what in [self.kinds, self.mixins, self.actions,
-                     self.resources, self.links]:
-            for el in what:
-                headers.append(("X-OCCI-Location", el.location))
-        return headers

ooi/occi/core/entity.py

@@ -22,6 +22,7 @@
 from ooi.occi.core import kind
 from ooi.occi.core import mixin
 from ooi.occi import helpers
+from ooi import utils
 
 
 class EntityMeta(type):
@@ -94,21 +95,4 @@ def title(self, value):
 
     @property
     def location(self):
-        return helpers.join_url(self.kind.location, self.id)
-
-    def headers(self):
-        """Render the entity to text/occi."""
-        h = self.kind.headers()
-        for m in self.mixins:
-            h.extend(m.headers())
-        for attr_name in self.attributes:
-            if self.attributes[attr_name].value is not None:
-                h.extend(self.attributes[attr_name].headers())
-        return h
-
-    def __str__(self):
-        """Render the entity to text/plain."""
-        ret = []
-        for h in self.headers():
-            ret.append(": ".join(h))
-        return "\n".join(ret)
+        return utils.join_url(self.kind.location, self.id)

ooi/occi/core/resource.py

@@ -60,10 +60,3 @@ def summary(self):
     @summary.setter
     def summary(self, value):
         self.attributes["occi.core.summary"].value = value
-
-    def __str__(self):
-        """Render the resource to text/plain."""
-        ret = [super(Resource, self).__str__()]
-        for link in self.links:
-            ret.append("%s" % link)
-        return "\n".join(ret)

ooi/occi/helpers.py

@@ -30,9 +30,3 @@ def check_type(obj_list, obj_type):
 
     if not all([isinstance(i, obj_type) for i in obj_list]):
         raise TypeError('object must be of class %s' % obj_type)
-
-
-def join_url(prefix, remainder, fragments=None):
-    if fragments:
-        remainder = "%s#%s" % (remainder, fragments)
-    return urlparse.urljoin(prefix, remainder)