maximum possible

survey/forms.py

@@ -25,6 +25,7 @@ class ResponseForm(models.ModelForm):
         Question.INTEGER: forms.IntegerField,
         Question.FLOAT: forms.FloatField,
         Question.DATE: forms.DateField,
+        Question.MAX: forms.IntegerField,
     }
 
     WIDGETS = {
@@ -301,3 +302,20 @@ def save(self, commit=True):
                 answer.save()
         survey_completed.send(sender=Response, instance=response, data=data)
         return response
+
+    def clean_choices(self, s):
+        value = self.cleaned_data
+        print(value)
+        for q in s.questions.all():
+            if q.type in ['select-multiple',] and q.maximum_choices:
+                """ Only for SELECT_MULTIPlE and if maximum_choices is set"""
+                question = q
+                max = question.maximum_choices
+                if value.get('question_%s' % question.id):
+                    """ Only if some answers are checked at all. """
+                    number_of_choices = len(value.get('question_%s' % question.id))
+                    if number_of_choices > max:
+                        LOGGER.info("Selected more Answers than allowed! Maximum is %d.", max)
+                        # TODO create a meaningful dialog for the user!
+                        return None
+        return value

survey/models/question.py

@@ -58,6 +58,7 @@ class Question(models.Model):
     INTEGER = "integer"
     FLOAT = "float"
     DATE = "date"
+    MAX = "maximum-coices"
 
     QUESTION_TYPES = (
         (TEXT, _("text (multiple line)")),
@@ -80,6 +81,7 @@ class Question(models.Model):
     survey = models.ForeignKey(Survey, on_delete=models.CASCADE, verbose_name=_("Survey"), related_name="questions")
     type = models.CharField(_("Type"), max_length=200, choices=QUESTION_TYPES, default=TEXT)
     choices = models.TextField(_("Choices"), blank=True, null=True, help_text=CHOICES_HELP_TEXT)
+    maximum_choices = models.IntegerField(_("Maximum possible Answers"),  blank=True, null=True)
 
     class Meta:
         verbose_name = _("question")

survey/views/survey_detail.py

@@ -57,7 +57,8 @@ def post(self, request, *args, **kwargs):
             return redirect(reverse("survey-list"))
         context = {"response_form": form, "survey": survey, "categories": categories}
         if form.is_valid():
-            return self.treat_valid_form(form, kwargs, request, survey)
+            if form.clean_choices(survey):
+                return self.treat_valid_form(form, kwargs, request, survey)
         return self.handle_invalid_form(context, form, request, survey)
 
     @staticmethod
@@ -88,7 +89,10 @@ def treat_valid_form(self, form, kwargs, request, survey):
             if not form.has_next_step():
                 save_form = ResponseForm(request.session[session_key], survey=survey, user=request.user)
                 if save_form.is_valid():
-                    response = save_form.save()
+                    if form.clean_choices(survey):
+                        response = save_form.save()
+                    else:
+                        return self.handle_invalid_form(context, form, request, survey)
                 else:
                     LOGGER.warning("A step of the multipage form failed but should have been discovered before.")
         # if there is a next step