Ensures tab data is preloaded. With tests! Fixes bug 964317.

Change-Id: I55ad1e0b9b836793ee2816cec18160b223f80462

horizon/tabs/base.py

@@ -89,6 +89,7 @@ class TabGroup(html.HTMLElement):
                                       % self.__class__)
         self.request = request
         self.kwargs = kwargs
+        self._data = None
         tab_instances = []
         for tab in self.tabs:
             tab_instances.append((tab.slug, tab(self, request)))
@@ -105,7 +106,11 @@ class TabGroup(html.HTMLElement):
         """
         for tab in self._tabs.values():
             if tab.load and not tab.data_loaded:
-                tab._data = tab.get_context_data(self.request)
+                try:
+                    tab._data = tab.get_context_data(self.request)
+                except:
+                    tab._data = False
+                    exceptions.handle(self.request)
 
     def get_id(self):
         """
@@ -262,7 +267,7 @@ class Tab(html.HTMLElement):
 
     @property
     def data(self):
-        if not getattr(self, "_data", None):
+        if getattr(self, "_data", None) is None:
             self._data = self.get_context_data(self.request)
         return self._data
 

horizon/tabs/views.py

@@ -38,6 +38,8 @@ class TabView(generic.TemplateView):
         try:
             tab_group = self.get_tabs(self.request, **kwargs)
             context["tab_group"] = tab_group
+            # Make sure our data is pre-loaded to capture errors.
+            context["tab_group"].load_tab_data()
         except:
             exceptions.handle(self.request)
         return context
@@ -111,12 +113,6 @@ class TabbedTableView(tables.MultiTableMixin, TabView):
         handled = tab._tables[table_name].maybe_handle()
         return handled
 
-    def get_context_data(self, **kwargs):
-        """ Adds the ``tab_group`` variable to the context data. """
-        context = super(TabbedTableView, self).get_context_data(**kwargs)
-        context['tab_group'].load_tab_data()
-        return context
-
     def get(self, request, *args, **kwargs):
         self.load_tabs()
         # Gather our table instances. It's important that they're the

horizon/test.py

@@ -49,6 +49,12 @@ wsgi.WSGIRequest.__repr__ = lambda self: "<class 'django.http.HttpRequest'>"
 
 
 class RequestFactoryWithMessages(RequestFactory):
+    def get(self, *args, **kwargs):
+        req = super(RequestFactoryWithMessages, self).get(*args, **kwargs)
+        req.session = []
+        req._messages = default_storage(req)
+        return req
+
     def post(self, *args, **kwargs):
         req = super(RequestFactoryWithMessages, self).post(*args, **kwargs)
         req.session = []
@@ -173,8 +179,13 @@ class TestCase(django_test.TestCase):
             if 'messages' in self.client.cookies:
                 message_cookie = self.client.cookies['messages'].value
                 messages = storage._decode(message_cookie)
-        elif "messages" in response.context:
+        # Check for messages in the context
+        elif hasattr(response, "context") and  "messages" in response.context:
             messages = response.context["messages"]
+        # Check for messages attached to the request on a TemplateResponse
+        elif hasattr(response, "_request") and hasattr(response._request,
+                                                       "_messages"):
+            messages = response._request._messages._queued_messages
 
         # If we don't have messages and we don't expect messages, we're done.
         if not any(kwargs.values()) and not messages:

horizon/tests/tabs_tests.py

@@ -14,9 +14,12 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import copy
+
 from django import http
 from django.utils.translation import ugettext_lazy as _
 
+from horizon import exceptions
 from horizon import tabs as horizon_tabs
 from horizon import test
 
@@ -77,9 +80,19 @@ class TabWithTable(horizon_tabs.TableTab):
         return TEST_DATA
 
 
+class RecoverableErrorTab(horizon_tabs.Tab):
+    name = _("Recoverable Error Tab")
+    slug = "recoverable_error_tab"
+    template_name = "_tab.html"
+
+    def get_context_data(self, request):
+        # Raise a known recoverable error.
+        raise exceptions.AlreadyExists("Recoverable!", None)
+
+
 class TableTabGroup(horizon_tabs.TabGroup):
     slug = "tab_group"
-    tabs = (TabWithTable,)
+    tabs = [TabWithTable]
 
 
 class TabWithTableView(horizon_tabs.TabbedTableView):
@@ -88,9 +101,6 @@ class TabWithTableView(horizon_tabs.TabbedTableView):
 
 
 class TabTests(test.TestCase):
-    def setUp(self):
-        super(TabTests, self).setUp()
-
     def test_tab_group_basics(self):
         tg = Group(self.request)
 
@@ -265,3 +275,26 @@ class TabTests(test.TestCase):
         res = view(req)
         self.assertEqual(res.status_code, 302)
         self.assertEqual(res["location"], "/")
+
+        # Ensure that lookup errors are raised as such instead of converted
+        # to TemplateSyntaxErrors.
+        action_string = "my_table__toggle__2000000000"
+        req = self.factory.post('/', {'action': action_string})
+        self.assertRaises(exceptions.Http302, view, req)
+
+
+class TabExceptionTests(test.TestCase):
+    def setUp(self):
+        super(TabExceptionTests, self).setUp()
+        self._original_tabs = copy.copy(TabWithTableView.tab_group_class.tabs)
+        TabWithTableView.tab_group_class.tabs.append(RecoverableErrorTab)
+
+    def tearDown(self):
+        super(TabExceptionTests, self).tearDown()
+        TabWithTableView.tab_group_class.tabs = self._original_tabs
+
+    def test_tab_view_exception(self):
+        view = TabWithTableView.as_view()
+        req = self.factory.get("/")
+        res = view(req)
+        self.assertMessageCount(res, error=1)