Fix handling of missing external network

When an external network can't be found, project/routers/index.html will
result in a type error caused by calling exceptions.handle when no
exception is present.  In this case, an error message should be
displayed, and the missing-network should be indicated to the user.

Also added tests for this case.

Change-Id: I3aaa64de28738051ad84cc587fbb6cfd546f4662
Closes-Bug: 1220345

openstack_dashboard/dashboards/admin/routers/tests.py

@@ -59,3 +59,21 @@ class RouterTests(test.BaseAdminViewTests, r_test.RouterTests):
         self.assertTemplateUsed(res, '%s/routers/index.html' % self.DASHBOARD)
         self.assertEqual(len(res.context['table'].data), 0)
         self.assertMessageCount(res, error=1)
+
+    @test.create_stubs({api.neutron: ('router_list', 'network_list')})
+    def test_set_external_network_empty(self):
+        router = self.routers.first()
+        api.neutron.router_list(
+            IsA(http.HttpRequest),
+            search_opts=None).AndReturn([router])
+        self._mock_external_network_list(alter_ids=True)
+        self.mox.ReplayAll()
+
+        res = self.client.get(self.INDEX_URL)
+
+        table_data = res.context['table'].data
+        self.assertEqual(len(table_data), 1)
+        self.assertIn('(Not Found)',
+                      table_data[0]['external_gateway_info']['network'])
+        self.assertTemplateUsed(res, '%s/routers/index.html' % self.DASHBOARD)
+        self.assertMessageCount(res, error=2)

openstack_dashboard/dashboards/project/routers/tests.py

@@ -15,6 +15,7 @@ import copy
 
 from django.core.urlresolvers import reverse
 from django import http
+
 from mox import IsA  # noqa
 
 from openstack_dashboard import api
@@ -28,9 +29,12 @@ class RouterTests(test.TestCase):
     INDEX_URL = reverse('horizon:%s:routers:index' % DASHBOARD)
     DETAIL_PATH = 'horizon:%s:routers:detail' % DASHBOARD
 
-    def _mock_external_network_list(self):
+    def _mock_external_network_list(self, alter_ids=False):
         search_opts = {'router:external': True}
         ext_nets = [n for n in self.networks.list() if n['router:external']]
+        if alter_ids:
+            for ext_net in ext_nets:
+                ext_net.id += 'some extra garbage'
         api.neutron.network_list(
             IsA(http.HttpRequest),
             **search_opts).AndReturn(ext_nets)
@@ -71,6 +75,25 @@ class RouterTests(test.TestCase):
         self.assertEqual(len(res.context['table'].data), 0)
         self.assertMessageCount(res, error=1)
 
+    @test.create_stubs({api.neutron: ('router_list', 'network_list')})
+    def test_set_external_network_empty(self):
+        router = self.routers.first()
+        api.neutron.router_list(
+            IsA(http.HttpRequest),
+            tenant_id=self.tenant.id,
+            search_opts=None).AndReturn([router])
+        self._mock_external_network_list(alter_ids=True)
+        self.mox.ReplayAll()
+
+        res = self.client.get(self.INDEX_URL)
+
+        table_data = res.context['table'].data
+        self.assertEqual(len(table_data), 1)
+        self.assertIn('(Not Found)',
+                      table_data[0]['external_gateway_info']['network'])
+        self.assertTemplateUsed(res, '%s/routers/index.html' % self.DASHBOARD)
+        self.assertMessageCount(res, error=1)
+
     @test.create_stubs({api.neutron: ('router_get', 'port_list',
                                       'network_get')})
     def test_router_detail(self):

openstack_dashboard/dashboards/project/routers/views.py

@@ -23,6 +23,7 @@ from django.utils.translation import ugettext_lazy as _
 
 from horizon import exceptions
 from horizon import forms
+from horizon import messages
 from horizon import tables
 from horizon import tabs
 from horizon.utils import memoized
@@ -80,8 +81,13 @@ class IndexView(tables.DataTableView):
             if ext_net_id in ext_net_dict:
                 gateway_info['network'] = ext_net_dict[ext_net_id]
             else:
-                msg = _('External network "%s" not found.') % (ext_net_id)
-                exceptions.handle(self.request, msg)
+                msg_params = {'ext_net_id': ext_net_id, 'router_id': router.id}
+                msg = _('External network "%(ext_net_id)s" expected but not '
+                        'found for router "%(router_id)s".') % msg_params
+                messages.error(self.request, msg)
+                # gateway_info['network'] is just the network name, so putting
+                # in a smallish error message in the table is reasonable.
+                gateway_info['network'] = _('%s (Not Found)') % ext_net_id
 
 
 class DetailView(tabs.TabbedTableView):
@@ -97,7 +103,7 @@ class DetailView(tabs.TabbedTableView):
             router.set_id_as_name_if_empty(length=0)
         except Exception:
             msg = _('Unable to retrieve details for router "%s".') \
-                % (router_id)
+                % router_id
             exceptions.handle(self.request, msg, redirect=self.failure_url)
         if router.external_gateway_info:
             ext_net_id = router.external_gateway_info['network_id']
@@ -108,7 +114,7 @@ class DetailView(tabs.TabbedTableView):
                 router.external_gateway_info['network'] = ext_net.name
             except Exception:
                 msg = _('Unable to retrieve an external network "%s".') \
-                    % (ext_net_id)
+                    % ext_net_id
                 exceptions.handle(self.request, msg)
                 router.external_gateway_info['network'] = ext_net_id
         return router