clean some js

- clean buttons code on account and checkout
- merge CheckoutRead and kpsul_checkout_data views (the first won)

APIModelObject interface
- add url_create, url_update, url_update_for
- rename url_object_for and url_object to url_read_for and url_read

kfet/views.py

@@ -52,6 +52,33 @@ from .statistic import daynames, monthnames, weeknames, \
         this_morning, this_monday_morning, this_first_month_day, \
         tot_ventes
 
+
+# source : docs.djangoproject.com/fr/1.10/topics/class-based-views/mixins/
+class JSONResponseMixin(object):
+    """
+    A mixin that can be used to render a JSON response.
+    """
+    def render_to_json_response(self, context, **response_kwargs):
+        """
+        Returns a JSON response, transforming 'context' to make the payload.
+        """
+        print(context)
+        return JsonResponse(
+            self.get_data(context),
+            **response_kwargs
+        )
+
+    def get_data(self, context):
+        """
+        Returns an object that will be serialized as JSON by json.dumps().
+        """
+        # Note: This is *EXTREMELY* naive; in reality, you'll need
+        # to do much more complex handling to ensure that arbitrary
+        # objects -- such as Django model instances or querysets
+        # -- can be serialized as JSON.
+        return context
+
+
 class Home(TemplateView):
     template_name   = "kfet/home.html"
 
@@ -618,18 +645,44 @@ class CheckoutCreate(SuccessMessageMixin, CreateView):
 
         return super(CheckoutCreate, self).form_valid(form)
 
+
 # Checkout - Read
 
-class CheckoutRead(DetailView):
+class CheckoutRead(JSONResponseMixin, DetailView):
     model = Checkout
     template_name = 'kfet/checkout_read.html'
     context_object_name = 'checkout'
 
     def get_context_data(self, **kwargs):
-        context = super(CheckoutRead, self).get_context_data(**kwargs)
-        context['statements'] = context['checkout'].statements.order_by('-at')
+        context = super().get_context_data(**kwargs)
+        checkout = self.object
+        if self.request.GET.get('last_statement'):
+            context['laststatement'] = checkout.statements.latest('at')
+        else:
+            context['statements'] = checkout.statements.order_by('-at')
         return context
 
+    def render_to_response(self, context, **kwargs):
+        if self.request.GET.get('format') == 'json':
+            data = model_to_dict(
+                context['checkout'],
+                fields=['id', 'name', 'balance', 'valid_from', 'valid_to']
+            )
+            if 'laststatement' in context:
+                last_statement = context['laststatement']
+                last_statement_data = model_to_dict(
+                    last_statement,
+                    fields=['id', 'at', 'balance_new', 'balance_old', 'by']
+                )
+                last_statement_data['by'] = str(last_statement.by)
+                # ``at`` is not editable, so skipped by ``model_to_dict``
+                last_statement_data['at'] = last_statement.at
+                data['laststatement'] = last_statement_data
+            return self.render_to_json_response(data)
+        else:
+            return super().render_to_response(context, **kwargs)
+
+
 # Checkout - Update
 
 class CheckoutUpdate(SuccessMessageMixin, UpdateView):
@@ -897,28 +950,6 @@ def kpsul_get_settings(request):
     return JsonResponse(data)
 
 
-@teamkfet_required
-def kpsul_checkout_data(request, pk):
-    checkout = get_object_or_404(Checkout, pk=pk)
-    data = model_to_dict(
-        checkout,
-        fields=['id', 'name', 'balance', 'valid_from', 'valid_to']
-    )
-
-    if request.GET.get('last_statement'):
-        last_statement = checkout.statements.latest('at')
-        last_statement_data = model_to_dict(
-            last_statement,
-            fields=['id', 'at', 'balance_new', 'balance_old', 'by']
-        )
-        last_statement_data['by'] = str(last_statement.by)
-        # ``at`` is not editable, so skipped by ``model_to_dict``
-        last_statement_data['at'] = last_statement.at
-        data['laststatement'] = last_statement_data
-
-    return JsonResponse(data)
-
-
 @teamkfet_required
 def kpsul_update_addcost(request):
     addcost_form = AddcostForm(request.POST)
@@ -2003,29 +2034,6 @@ class SupplierUpdate(SuccessMessageMixin, UpdateView):
 # ---------------
 # Vues génériques
 # ---------------
-# source : docs.djangoproject.com/fr/1.10/topics/class-based-views/mixins/
-class JSONResponseMixin(object):
-    """
-    A mixin that can be used to render a JSON response.
-    """
-    def render_to_json_response(self, context, **response_kwargs):
-        """
-        Returns a JSON response, transforming 'context' to make the payload.
-        """
-        return JsonResponse(
-            self.get_data(context),
-            **response_kwargs
-        )
-
-    def get_data(self, context):
-        """
-        Returns an object that will be serialized as JSON by json.dumps().
-        """
-        # Note: This is *EXTREMELY* naive; in reality, you'll need
-        # to do much more complex handling to ensure that arbitrary
-        # objects -- such as Django model instances or querysets
-        # -- can be serialized as JSON.
-        return context
 
 
 class JSONDetailView(JSONResponseMixin,