Uniquify horizon messages returned in a single response

A network operation can fail because of different
reasons - yet in many places just one error message
is provided. Combined with too broad exception clause,
and incorrect assumptions on the reasons of failure
(e.g. Neutron service being unavailable causes all
other sorts of errors like inability to Allocate IP
or Associate it) this leads to multiple errors when just one
would suffice. The fix aims to provide sensible error
messages in case the network service is down. This includes
returning only unique messages in a single response.

Partial-Bug: #1301374
Change-Id: Id6c620ca51f7703f35c0c172e39fdf237fa42278
Co-Authored-By: Timur Sufiev <tsufiev@mirantis.com>

horizon/messages.py

@@ -23,20 +23,34 @@ from django.utils.encoding import force_text
 from django.utils.safestring import SafeData  # noqa
 
 
+def horizon_message_already_queued(request, message):
+    _message = force_text(message)
+    if request.is_ajax():
+        for tag, msg, extra in request.horizon['async_messages']:
+            if _message == msg:
+                return True
+    else:
+        for msg in _messages.get_messages(request)._queued_messages:
+            if msg.message == _message:
+                return True
+    return False
+
+
 def add_message(request, level, message, extra_tags='', fail_silently=False):
     """Attempts to add a message to the request using the 'messages' app."""
-    if request.is_ajax():
-        tag = constants.DEFAULT_TAGS[level]
-        # if message is marked as safe, pass "safe" tag as extra_tags so that
-        # client can skip HTML escape for the message when rendering
-        if isinstance(message, SafeData):
-            extra_tags = extra_tags + ' safe'
-        request.horizon['async_messages'].append([tag,
-                                                  force_text(message),
-                                                  extra_tags])
-    else:
-        return _messages.add_message(request, level, message,
-                                     extra_tags, fail_silently)
+    if not horizon_message_already_queued(request, message):
+        if request.is_ajax():
+            tag = constants.DEFAULT_TAGS[level]
+            # if message is marked as safe, pass "safe" tag as extra_tags so
+            # that client can skip HTML escape for the message when rendering
+            if isinstance(message, SafeData):
+                extra_tags = extra_tags + ' safe'
+            request.horizon['async_messages'].append([tag,
+                                                      force_text(message),
+                                                      extra_tags])
+        else:
+            return _messages.add_message(request, level, message,
+                                         extra_tags, fail_silently)
 
 
 def debug(request, message, extra_tags='', fail_silently=False):

openstack_dashboard/dashboards/admin/instances/tests.py

@@ -118,7 +118,10 @@ class InstanceViewTest(test.BaseAdminViewTests):
         res = self.client.get(INDEX_URL)
         instances = res.context['table'].data
         self.assertTemplateUsed(res, 'admin/instances/index.html')
-        self.assertMessageCount(res, error=len(servers))
+        # Since error messages produced for each instance are identical,
+        # there will be only one error message for all instances
+        # (messages de-duplication).
+        self.assertMessageCount(res, error=1)
         self.assertItemsEqual(instances, servers)
 
     @test.create_stubs({api.nova: ('server_list',)})

openstack_dashboard/dashboards/project/access_and_security/floating_ips/views.py

@@ -24,6 +24,8 @@ Views for managing floating IPs.
 from django.core.urlresolvers import reverse_lazy
 from django.utils.translation import ugettext_lazy as _
 
+from neutronclient.common import exceptions as neutron_exc
+
 from horizon import exceptions
 from horizon import forms
 from horizon import workflows
@@ -60,6 +62,9 @@ class AllocateView(forms.ModalFormView):
     def get_initial(self):
         try:
             pools = api.network.floating_ip_pools_list(self.request)
+        except neutron_exc.ConnectionFailed:
+            pools = []
+            exceptions.handle(self.request)
         except Exception:
             pools = []
             exceptions.handle(self.request,

openstack_dashboard/dashboards/project/access_and_security/floating_ips/workflows.py

@@ -15,6 +15,8 @@
 from django.core.urlresolvers import reverse
 from django.utils.translation import ugettext_lazy as _
 
+from neutronclient.common import exceptions as neutron_exc
+
 from horizon import exceptions
 from horizon import forms
 from horizon import workflows
@@ -59,10 +61,12 @@ class AssociateIPAction(workflows.Action):
 
     def populate_ip_id_choices(self, request, context):
         ips = []
+        redirect = reverse('horizon:project:access_and_security:index')
         try:
             ips = api.network.tenant_floating_ip_list(self.request)
+        except neutron_exc.ConnectionFailed:
+            exceptions.handle(self.request, redirect=redirect)
         except Exception:
-            redirect = reverse('horizon:project:access_and_security:index')
             exceptions.handle(self.request,
                               _('Unable to retrieve floating IP addresses.'),
                               redirect=redirect)

openstack_dashboard/dashboards/project/access_and_security/tabs.py

@@ -22,6 +22,8 @@ from django.utils.translation import ugettext_lazy as _
 from horizon import exceptions
 from horizon import tabs
 
+from neutronclient.common import exceptions as neutron_exc
+
 from openstack_dashboard.api import keystone
 from openstack_dashboard.api import network
 from openstack_dashboard.api import nova
@@ -46,6 +48,9 @@ class SecurityGroupsTab(tabs.TableTab):
     def get_security_groups_data(self):
         try:
             security_groups = network.security_group_list(self.request)
+        except neutron_exc.ConnectionFailed:
+            security_groups = []
+            exceptions.handle(self.request)
         except Exception:
             security_groups = []
             exceptions.handle(self.request,
@@ -80,6 +85,9 @@ class FloatingIPsTab(tabs.TableTab):
     def get_floating_ips_data(self):
         try:
             floating_ips = network.tenant_floating_ip_list(self.request)
+        except neutron_exc.ConnectionFailed:
+            floating_ips = []
+            exceptions.handle(self.request)
         except Exception:
             floating_ips = []
             exceptions.handle(self.request,
@@ -87,6 +95,9 @@ class FloatingIPsTab(tabs.TableTab):
 
         try:
             floating_ip_pools = network.floating_ip_pools_list(self.request)
+        except neutron_exc.ConnectionFailed:
+            floating_ip_pools = []
+            exceptions.handle(self.request)
         except Exception:
             floating_ip_pools = []
             exceptions.handle(self.request,

openstack_dashboard/dashboards/project/instances/tests.py

@@ -198,7 +198,10 @@ class InstanceTests(helpers.TestCase):
         instances = res.context['instances_table'].data
 
         self.assertTemplateUsed(res, 'project/instances/index.html')
-        self.assertMessageCount(res, error=len(servers))
+        # Since error messages produced for each instance are identical,
+        # there will be only one error message for all instances
+        # (messages de-duplication)
+        self.assertMessageCount(res, error=1)
         self.assertItemsEqual(instances, self.servers.list())
 
     @helpers.create_stubs({