Views accessible via url even if user doesn't match policy rules

When a user doesn't match the policy rules of a panel then the panel tab
is removed from the menu of the left, but panel views are still
accessible using directly the url (ex /admin/flavors/).

In most of the case, views won't work correctly because of the lack of
right in the backend, but it may cause trouble when you play with
policies.

I think it could be more elegant to return directly a "You are not
authorized to access this page" from the frontend when user try to
access a view of a panel (via url) without matching the policy rules.

Change-Id: I7bc93fed29568adfc14d5bcadfc8728d3b5cf633
Closes-Bug: #1741051

horizon/base.py

@@ -43,6 +43,7 @@ import six
 from horizon import conf
 from horizon.decorators import _current_component
 from horizon.decorators import require_auth
+from horizon.decorators import require_component_access
 from horizon.decorators import require_perms
 from horizon import loaders
 from horizon.utils import settings as utils_settings
@@ -320,6 +321,8 @@ class Panel(HorizonComponent):
         # Apply access controls to all views in the patterns
         permissions = getattr(self, 'permissions', [])
         _decorate_urlconf(urlpatterns, require_perms, permissions)
+        _decorate_urlconf(
+            urlpatterns, require_component_access, component=self)
         _decorate_urlconf(urlpatterns, _current_component, panel=self)
 
         # Return the three arguments to django.conf.urls.include

horizon/decorators.py

@@ -90,3 +90,26 @@ def require_perms(view_func, required):
         return dec
     else:
         return view_func
+
+
+def require_component_access(view_func, component):
+    """Perform component can_access check to access the view.
+
+    :param component containing the view (panel or dashboard).
+
+    Raises a :exc:`~horizon.exceptions.NotAuthorized` exception if the
+    user cannot access the component containing the view.
+    By example the check of component policy rules will be applied to its
+    views.
+    """
+    from horizon.exceptions import NotAuthorized
+
+    @functools.wraps(view_func, assigned=available_attrs(view_func))
+    def dec(request, *args, **kwargs):
+        if not component.can_access({'request': request}):
+            raise NotAuthorized(_("You are not authorized to access %s")
+                                % request.path)
+
+        return view_func(request, *args, **kwargs)
+
+    return dec

openstack_dashboard/test/settings.py

@@ -297,6 +297,11 @@ TEST_GLOBAL_MOCKS_ON_PANELS = {
                    '.aggregates.panel.Aggregates.can_access'),
         'return_value': True,
     },
+    'domains': {
+        'method': ('openstack_dashboard.dashboards.identity'
+                   '.domains.panel.Domains.can_access'),
+        'return_value': True,
+    },
     'trunk-project': {
         'method': ('openstack_dashboard.dashboards.project'
                    '.trunks.panel.Trunks.can_access'),