Fix addition of plugin panel to panel group

Revert fix from bug #1329050, which adds a plugin panel to its dashboard's
class. Adding a plugin panel to a dashboard whose class has its panels defined
in a tuple will fail because the new plugin cannot be appended to the tuple.
The code errors out before the panel gets added to the dashboard's panel list.
However, at this point, the panel has already been registered with the
dashboard. This causes Dashboard.get_panels() to see the panel in its registry
but not in its panel groups. Consequently, the panel gets put in the "Other"
panel group instead of its configured one, as described in bug #1378558.

By not adding the the plugin panel to its dashboard's class, the panel gets
added to its dashboard's panel list. Now the original issue from bug #1329050
resurfaces. The root cause of that is that every time Dashboard._autodiscover()
is called, it instantiates all its panel group classes, wiping out any panels
previously added to any of the panel groups. Avoid this by always processing
all the plugin panel groups before any of the plugin panels, which also ensures
that the panel groups exist before their panels.

Making this change exposed an issue where the Horizon URLs were being loaded
twice during the plugin infrastructure's unit tests, causing plugin panels to
be added multiple times to their dashboards. Fix that by removing the second,
unnecessary call. Also create a second test plugin panel group and panel to
test the scenarios described in the two bugs addressed here, adding two panel
groups at a time.

Change-Id: Id6a99c3ff18102c8f47431638d4dda98f14ec641
Closes-Bug: 1378558
(cherry picked from commit e2ef492311)
(cherry picked from commit 5c1604275b)

horizon/base.py

@@ -847,14 +847,21 @@ class Site(Registry, HorizonComponent):
         """
         panel_customization = self._conf.get("panel_customization", [])
 
+        # Process all the panel groups first so that they exist before panels
+        # are added to them and Dashboard._autodiscover() doesn't wipe out any
+        # panels previously added when its panel groups are instantiated.
+        panel_configs = []
         for config in panel_customization:
             if config.get('PANEL'):
-                self._process_panel_configuration(config)
+                panel_configs.append(config)
             elif config.get('PANEL_GROUP'):
                 self._process_panel_group_configuration(config)
             else:
                 LOG.warning("Skipping %s because it doesn't have PANEL or "
                             "PANEL_GROUP defined.", config.__name__)
+        # Now process the panels.
+        for config in panel_configs:
+            self._process_panel_configuration(config)
 
     def _process_panel_configuration(self, config):
         """Add, remove and set default panels on the dashboard."""
@@ -890,8 +897,6 @@ class Site(Registry, HorizonComponent):
                 panel = getattr(mod, panel_cls)
                 dashboard_cls.register(panel)
                 if panel_group:
-                    dashboard_cls.get_panel_group(panel_group).__class__.\
-                        panels.append(panel.slug)
                     dashboard_cls.get_panel_group(panel_group).\
                         panels.append(panel.slug)
                 else:

openstack_dashboard/test/helpers.py

@@ -454,9 +454,6 @@ class PluginTestCase(TestCase):
         self.old_horizon_config = conf.HORIZON_CONFIG
         conf.HORIZON_CONFIG = conf.LazySettings()
         base.Horizon._urls()
-        # Trigger discovery, registration, and URLconf generation if it
-        # hasn't happened yet.
-        self.client.get("/")
         # Store our original dashboards
         self._discovered_dashboards = base.Horizon._registry.keys()
         # Gather up and store our original panels for each dashboard

openstack_dashboard/test/test_panels/plugin_panel/views.py

@@ -15,3 +15,4 @@ from django.views.generic import TemplateView  # noqa
 
 class IndexView(TemplateView):
     template_name = 'admin/plugin_panel/index.html'
+    page_title = 'Plugin-based Panel'

openstack_dashboard/test/test_panels/second_panel/panel.py

@@ -0,0 +1,18 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import horizon
+
+
+class SecondPanel(horizon.Panel):
+    name = "Second Plugin Panel"
+    slug = 'second_panel'

openstack_dashboard/test/test_panels/second_panel/templates/second_panel/index.html

@@ -0,0 +1,11 @@
+{% extends 'base.html' %}
+{% load i18n %}
+{% block title %}Second Plugin-based Panel{% endblock %}
+
+{% block main %}
+<div class="row">
+  <div class="col-sm-12">
+    Second Plugin-based Panel
+  </div>
+</div>
+{% endblock %}

openstack_dashboard/test/test_panels/second_panel/urls.py

@@ -0,0 +1,21 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from django.conf.urls import patterns
+from django.conf.urls import url
+
+from openstack_dashboard.test.test_panels.second_panel import views
+
+urlpatterns = patterns(
+    '',
+    url(r'^$', views.IndexView.as_view(), name='index'),
+)

openstack_dashboard/test/test_panels/second_panel/views.py

@@ -0,0 +1,18 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from django.views.generic import TemplateView  # noqa
+
+
+class IndexView(TemplateView):
+    template_name = 'admin/second_panel/index.html'
+    page_title = 'Second Plugin-based Panel'

openstack_dashboard/test/test_plugins/panel_group_config/_30_admin_add_second_panel_group.py

@@ -0,0 +1,6 @@
+# The name of the panel group to be added to HORIZON_CONFIG. Required.
+PANEL_GROUP = 'second_panel_group'
+# The display name of the PANEL_GROUP. Required.
+PANEL_GROUP_NAME = 'Second Plugin Panel Group'
+# The name of the dashboard the PANEL_GROUP associated with. Required.
+PANEL_GROUP_DASHBOARD = 'admin'

openstack_dashboard/test/test_plugins/panel_group_config/_40_admin_add_panel_to_second_group.py

@@ -0,0 +1,10 @@
+# The name of the panel to be added to HORIZON_CONFIG. Required.
+PANEL = 'second_panel'
+# The name of the dashboard the PANEL associated with. Required.
+PANEL_DASHBOARD = 'admin'
+# The name of the panel group the PANEL is associated with.
+PANEL_GROUP = 'second_panel_group'
+
+# Python panel class of the PANEL to be added.
+ADD_PANEL = \
+    'openstack_dashboard.test.test_panels.second_panel.panel.SecondPanel'

openstack_dashboard/test/test_plugins/panel_group_tests.py

@@ -20,11 +20,14 @@ import horizon
 from openstack_dashboard.test import helpers as test
 from openstack_dashboard.test.test_panels.plugin_panel \
     import panel as plugin_panel
+from openstack_dashboard.test.test_panels.second_panel \
+    import panel as second_panel
 import openstack_dashboard.test.test_plugins.panel_group_config
 from openstack_dashboard.utils import settings as util_settings
 
 
 PANEL_GROUP_SLUG = 'plugin_panel_group'
+SECOND_PANEL_GROUP_SLUG = 'second_panel_group'
 HORIZON_CONFIG = copy.deepcopy(settings.HORIZON_CONFIG)
 INSTALLED_APPS = list(settings.INSTALLED_APPS)
 
@@ -40,7 +43,31 @@ class PanelGroupPluginTests(test.PluginTestCase):
         dashboard = horizon.get_dashboard("admin")
         self.assertIsNotNone(dashboard.get_panel_group(PANEL_GROUP_SLUG))
 
-    def test_add_panel(self):
+    def test_add_second_panel_group(self):
+        # Check that the second panel group was added to the dashboard.
         dashboard = horizon.get_dashboard("admin")
+        self.assertIsNotNone(
+            dashboard.get_panel_group(SECOND_PANEL_GROUP_SLUG))
+
+    def test_add_panel(self):
+        # Check that the panel is in its configured dashboard and panel group.
+        dashboard = horizon.get_dashboard("admin")
+        panel_group = dashboard.get_panel_group(PANEL_GROUP_SLUG)
         self.assertIn(plugin_panel.PluginPanel,
                       [p.__class__ for p in dashboard.get_panels()])
+        self.assertIn(plugin_panel.PluginPanel,
+                      [p.__class__ for p in panel_group])
+
+    def test_add_second_panel(self):
+        # Check that the second panel is in its configured dashboard and panel
+        # group.
+        dashboard = horizon.get_dashboard("admin")
+        second_panel_group = dashboard.get_panel_group(SECOND_PANEL_GROUP_SLUG)
+        self.assertIn(second_panel.SecondPanel,
+                      [p.__class__ for p in dashboard.get_panels()])
+        self.assertIn(second_panel.SecondPanel,
+                      [p.__class__ for p in second_panel_group])
+
+    def test_unregistered_panel_group(self):
+        dashboard = horizon.get_dashboard("admin")
+        self.assertNotIn("nonexistent_panel", dashboard.get_panel_groups())

openstack_dashboard/test/test_plugins/panel_tests.py

@@ -38,13 +38,23 @@ util_settings.update_dashboards([
 class PanelPluginTests(test.PluginTestCase):
     def test_add_panel(self):
         dashboard = horizon.get_dashboard("admin")
+        panel_group = dashboard.get_panel_group('admin')
+        # Check that the panel is in its configured dashboard.
         self.assertIn(plugin_panel.PluginPanel,
                       [p.__class__ for p in dashboard.get_panels()])
+        # Check that the panel is in its configured panel group.
+        self.assertIn(plugin_panel.PluginPanel,
+                      [p.__class__ for p in panel_group])
 
     def test_remove_panel(self):
         dashboard = horizon.get_dashboard("admin")
+        panel_group = dashboard.get_panel_group('admin')
+        # Check that the panel is no longer in the configured dashboard.
         self.assertNotIn(info_panel.Info,
                          [p.__class__ for p in dashboard.get_panels()])
+        # Check that the panel is no longer in the configured panel group.
+        self.assertNotIn(info_panel.Info,
+                         [p.__class__ for p in panel_group])
 
     def test_default_panel(self):
         dashboard = horizon.get_dashboard("admin")