dashboard: os for instances without template

circle/dashboard/templates/dashboard/vm-detail/home.html

@@ -3,7 +3,7 @@
   <div class="col-md-4">
     <dl>
       <dt>System:</dt>
-      <dd><i class="icon-{{ instance.template.os_type }}"></i> {{ instance.template.system }}</dd>
+      <dd><i class="icon-{{ os_type_icon }}"></i> {{ instance.system }}</dd>
       <dt style="margin-top: 5px;">Description:</dt>
       <dd><small>{{ instance.description }}</small></dd>
     </dl>

circle/dashboard/views.py

@@ -156,6 +156,8 @@ class VmDetailView(CheckedDetailView):
         context['forms'] = {
             'disk_add_form': DiskAddForm(prefix="disk"),
         }
+        context['os_type_icon'] = instance.os_type.replace("unknown",
+                                                           "question")
         return context
 
     def post(self, request, *args, **kwargs):

circle/vm/models/instance.py

@@ -380,6 +380,24 @@ class Instance(AclBase, VirtualMachineDescModel, TimeStampedModel):
         else:
             return timedelta()  # zero
 
+    @property
+    def os_type(self):
+        """Get the type of the instance's operating system.
+        """
+        if self.template is None:
+            return "unknown"
+        else:
+            return self.template.os_type
+
+    @property
+    def system(self):
+        """Get the instance's operating system.
+        """
+        if self.template is None:
+            return _("Unknown")
+        else:
+            return self.template.system
+
     def get_age(self):
         """Deprecated. Use uptime instead.