Add error message if a invalid answer was send via POST to a QuestionView. Fix #940.

CHANGELOG

@@ -22,8 +22,8 @@ Other:
 - Full text search integration (with Haystack and Whoosh).
 - New start script with new command line options.
 - Fixed keyerror on user settings view.
-- New message on success of many actions like creating or editing objects.
-- Added Feature to config app to return the default value for a key.
+- New messages on success or error of many actions like creating or editing objects.
+- Added feature to config app to return the default value for a key.
 - Cleaned up OpenSlides utils views.
 - Used flake8 instead of pep8 for style check, sort all import statements with isort.
 - Added Portuguese translation (Thanks to Marco A.G.Pinto).

openslides/agenda/views.py

@@ -270,20 +270,29 @@ class ItemDelete(DeleteView):
             self.item_delete_answer_options = options
         return options
 
-    def pre_post_redirect(self, request, *args, **kwargs):
-        # TODO: rewrite this method with on_case_all and on_case_yes
-        if self.get_answer() == 'all':
-            self.object.delete(with_children=True)
-            messages.success(
-                request,
-                _("Item %s and his children were successfully deleted.")
-                % html_strong(self.object))
-        elif self.get_answer() == 'yes':
+    def on_clicked_yes(self):
+        """
+        Deletes the item but not its children.
+        """
         self.object.delete(with_children=False)
-            messages.success(
-                request,
-                _("Item %s was successfully deleted.")
-                % html_strong(self.object))
+
+    def on_clicked_all(self):
+        """
+        Deletes the item and its children.
+        """
+        self.object.delete(with_children=True)
+
+    def get_final_message(self):
+        """
+        Prints the success message to the user.
+        """
+        # OpenSlidesError (invalid answer) should never be raised here because
+        # this method should only be called if the answer is 'yes' or 'all'.
+        if self.get_answer() == 'yes':
+            message = _('Item %s was successfully deleted.') % html_strong(self.object)
+        else:
+            message = _('Item %s and its children were successfully deleted.') % html_strong(self.object)
+        return message
 
 
 class CreateRelatedAgendaItemView(SingleObjectMixin, RedirectView):

openslides/utils/views.py

@@ -33,6 +33,7 @@ from django.views.generic.detail import SingleObjectMixin
 from reportlab.lib.units import cm
 from reportlab.platypus import SimpleDocTemplate, Spacer
 
+from .exceptions import OpenSlidesError
 from .pdf import firstPage, laterPages
 from .signals import template_manipulation
 from .utils import html_strong
@@ -400,14 +401,18 @@ class QuestionView(RedirectView):
         """
         Calls the method for the answer the user clicked.
 
-        The method name is on_clicked_ANSWER where ANSWER is the key from the
-        clicked answer. See get_answer_options. If this method is not defined,
-        raises a NotImplementedError.
-
-        If the method returns True, then the success message is printed to the
-        user.
+        The method name is on_clicked_ANSWER where ANSWER is the key from
+        the clicked answer. See get_answer_options. Prints an error
+        message, if no valid answer was given. If this method is not
+        defined, nothing happens, else it is called and the success message
+        is printed to the user.
         """
-        method_name = 'on_clicked_%s' % self.get_answer()
+        try:
+            answer = self.get_answer()
+        except OpenSlidesError as error:
+            messages.error(self.request, error)
+        else:
+            method_name = 'on_clicked_%s' % answer
             method = getattr(self, method_name, None)
             if method is None:
                 pass
@@ -419,13 +424,15 @@ class QuestionView(RedirectView):
         """
         Returns the key of the clicked answer.
 
-        Raises ImproperlyConfigured, if the answer is not one of
-        get_answer_options.
+        Raises OpenSlidesError if the answer is not one of get_answer_options.
         """
         for option_key, option_name in self.get_answer_options():
             if option_key in self.request.POST:
-                return option_key
-        raise ImproperlyConfigured('%s is not a valid answer' % self.request.POST)
+                answer = option_key
+                break
+        else:
+            raise OpenSlidesError(ugettext_lazy('You did not send a valid answer.'))
+        return answer
 
     def get_final_message(self):
         """
@@ -493,18 +500,26 @@ class DeleteView(SingleObjectMixin, QuestionView):
     def get_redirect_url(self, **kwargs):
         """
         Returns the url on which the delete dialog is shown and the url after
-        the deleten.
+        the deleting.
 
-        On GET-requests and on aborted POST-requests, redirect to the detail
+        On GET-requests and on aborted or failed POST-requests, redirects to the detail
         view as default. The attributes question_url_name or question_url can
         define other urls.
         """
-        if self.request.method == 'GET' or self.get_answer() == 'no':
+        if self.request.method == 'POST':
+            try:
+                answer = self.get_answer()
+            except OpenSlidesError:
+                answer = 'no'
+            if answer == 'no':
                 url = self.get_url(self.question_url_name, self.question_url,
                                    args=self.get_url_name_args())
             else:
                 url = self.get_url(self.success_url_name, self.success_url,
                                    args=self.get_url_name_args())
+        else:
+            url = self.get_url(self.question_url_name, self.question_url,
+                               args=self.get_url_name_args())
         return url
 
     def get_question_message(self):

tests/agenda/tests.py

@@ -222,6 +222,13 @@ class ViewTest(TestCase):
         query = Item.objects.filter(pk__in=[item1.pk, item2.pk])
         self.assertFalse(query)
 
+    def test_delete_item_with_wrong_answer(self):
+        response = self.adminClient.post(
+            '/agenda/%s/del/' % self.item1.pk,
+            {'unknown_answer_aicipohc1Eeph2chaeng': 1})
+        self.assertRedirects(response, '/agenda/')
+        self.assertTrue(Item.objects.filter(pk=self.item1.pk).exists())
+
 
 class ConfigTest(TestCase):
     def setUp(self):