update cornice blogpost

content/mozilla/introducing-cornice.rst

@@ -3,14 +3,53 @@ Introducing cornice
 
 :date: 06/12/2011
 
-Wow, this is my second working day at mozilla. I've been working, yesterday and
-today, on a pyramid REST-ish toolkit, `cornice <https://github.com/mozilla-services/cornice>`_.
+Wow, already my third working day at mozilla. Since Monday, I've been working with
+Tarek Ziadé, on a pyramid REST-ish toolkit named `cornice <https://github.com/mozilla-services/cornice>`_.
 
-Cornice allows you to take out from you all the repetitive stuff you do when
-writing a web service. I'm mainly thinking about different kinds of validation.
+Its goal is to take all the hard bits appart from you when implementing a web
+service, so you can focus on what's important. Cornice provides you facilities
+for validation of any kind.
+
+The goal is to simplify your work, but we don't want to reinvent the wheel, so
+it is easily pluggable with validations frameworks, such as Collander.
+
+Handling errors and validation
+==============================
+
+We have changed the way errors are handled. Here is how it works:
+
+.. code-block:: python
+
+    service = Service(name="service", path="/service")
+
+
+    def is_awesome(request):
+        if not 'awesome' in request.GET:
+            request.errors.add('body', 'awesome', 'You lack awesomeness!')
+
+
+    @service.get(validator=(is_awesome))
+    def get1(request):
+        return {"test": "succeeded"}
+
+
+All the errors collected during the validation process, or after, are collected
+before returning the request. If any, a error 400 is fired up, with the list of
+problems encoutred encoded as a nice json list (we plan to support multiple
+formats in the future)
+
+As you might have seen, `request.errors.add` takes three parameters: **location**,
+**name** and **description**.
+
+**location** is where the error arised. It can either be "body", "query", "headers"
+or "path". **name** is the name of the variable causing problem, if any, and
+**description** contains a more detailled message.
+
+Here is an example of a malformed request::
+
+    $ # run a demo app
 
 To describe a web service in *cornice*, you have to write something like this
 
 .. code-block:: python
     
-