Aggregate nodes in error message

Each node, which has unreachable monitor info shown in one error message.

circle/dashboard/views/node.py

@@ -193,7 +193,6 @@ class NodeList(LoginRequiredMixin, GraphMixin, SingleTableView):
     def get(self, *args, **kwargs):
         if not self.request.user.has_perm('vm.view_statistics'):
             raise PermissionDenied()
-        self.wrong_nodes_message()
         if self.request.is_ajax():
             nodes = Node.objects.all()
             nodes = [{
@@ -211,14 +210,20 @@ class NodeList(LoginRequiredMixin, GraphMixin, SingleTableView):
             return super(NodeList, self).get(*args, **kwargs)
 
     def get_queryset(self):
+        self.wrong_nodes_message()
         return Node.objects.annotate(
             number_of_VMs=Count('instance_set')).select_related('host')
 
     def wrong_nodes_message(self):
+        wrong_nodes = ''
         for node in Node.objects.all():
             if node.monitor_info is None:
-                messages.error(self.request,
-                               "Can't reach " + node.name + " monitor info")
+                if wrong_nodes != '':
+                    wrong_nodes += ','
+                wrong_nodes += ' ' + node.name
+        if wrong_nodes != '':
+            messages.error(self.request,
+                           "Can't reach" + wrong_nodes + " monitor info")
 
 
 class NodeCreate(LoginRequiredMixin, SuperuserRequiredMixin, TemplateView):

circle/vm/models/node.py

@@ -364,6 +364,8 @@ class Node(OperatedMixin, TimeStampedModel):
         return self.info.get('driver_version')
 
     def get_monitor_info(self, metric):
+        # return with the metric value if the monitor info not none
+        # or return 0 if its None or the metric unreachable
         if self.monitor_info is None:
             return 0
         elif self.monitor_info.get(metric) is None: