django Wie man einen MinLengthValidator Validator in einem Formular hinzufügt

Question

Ich habe ein Suchformular und ich möchte bestätigen, dass die Eingabe 'seach_word' mindestens 4 Buchstaben hat. Ich bekomme diesen Fehler, wenn ich versuche, meine Formulare zu validieren

Der Antwortinhalt muss gerendert werden, bevor es iteriert werden kann.

#views.py 
class SearchFormView(FormView): 
    form_class = PostSearchForm 
    template_name = 'lineup/post_search.html' 

    def form_valid(self, form): 
     schWord = form.cleaned_data['search_word'] 
     search_type = form.cleaned_data['search_type'] 
     context = {} 

     if search_type == 'store': 
      post_list = Store.objects.filter(
        Q(cie_name__icontains=schWord)).distinct() 
      context['object_type'] = 'store' 
      context['object_list'] = post_list 

     if search_type == 'city': 
      post_list = Address.objects.filter(
        Q(city__icontains=schWord)).distinct() 
      context['object_type'] = 'city' 
      context['object_list'] = post_list 

     context['form'] = form 
     context['search_term'] = schWord 
     return render(self.request, self.template_name, context) 

    def form_invalid(self, form): 
     schWord = form.cleaned_data['search_word'] 
     messages.add_message(
     self.request, messages.WARNING, _('Please correct this...')) 
     context = super(SearchFormView, self).form_invalid(form) 
     return render(self.request, self.template_name, context) 

Inhalt forms.py

#forms.py 
class PostSearchForm(forms.Form): 
    SEARCH_TYPE_CHOICES = (
     ('city', 'city'), 
     ('store', 'store'), 
     ('product', 'product'), 
     ) 
    search_type = forms.ChoiceField(choices=SEARCH_TYPE_CHOICES, required=True) 
    search_word = forms.CharField(label='Search Word', 
        validators=[MinLengthValidator(4)], required=True) 
    ''' 
    def clean_search_word(self): 
     cd = self.cleaned_data 
     if len(cd['search_word']) < 4: 
      raise forms.ValidationError('too short.') 
     return cd['search_word'] 
    ''' 
    def __init__(self, *args, **kwargs): 
     self.helper = FormHelper() 
     self.helper.form_tag = False 
     self.helper.layout = Layout(
      Fieldset(
       '', 
       Field('search_type', css_class='span6'), 
       Field('search_word', css_class='span6'), 
      ), 
      FormActions(
       Submit('submit', 'Go', css_class='btn btn-primary') 
      ) 
     ) 
     super(PostSearchForm, self).__init__(*args, **kwargs) 

tracenack

Environment: 


Request Method: POST 
Request URL: http://localhost:8000/search/ 

Django Version: 1.10.3 
Python Version: 3.5.2 
Installed Applications: 
['grappelli', 
'django.contrib.admin', 
'django.contrib.auth', 
'django.contrib.contenttypes', 
'django.contrib.sessions', 
'django.contrib.messages', 
'django.contrib.staticfiles', 
'django.contrib.sites', 
'debug_toolbar', 
'stripe', 
'vote', 
'django_messages', 
'pinax.notifications', 
'admin_honeypot', 
'easy_thumbnails', 
'django_extensions', 
'crispy_forms', 
'datetimewidget', 
'lineup', 
'allauth', 
'allauth.account', 
'allauth.socialaccount'] 
Installed Middleware: 
['django.middleware.security.SecurityMiddleware', 
'django.contrib.sessions.middleware.SessionMiddleware', 
'django.middleware.common.CommonMiddleware', 
'django.middleware.csrf.CsrfViewMiddleware', 
'django.contrib.auth.middleware.AuthenticationMiddleware', 
'django.contrib.messages.middleware.MessageMiddleware', 
'django.middleware.clickjacking.XFrameOptionsMiddleware', 
'debug_toolbar.middleware.DebugToolbarMiddleware', 
'django.middleware.locale.LocaleMiddleware'] 


File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/core/handlers/exception.py" in inner 
    39.    response = get_response(request) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/core/handlers/base.py" in _get_response 
    187.     response = self.process_exception_by_middleware(e, request) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/core/handlers/base.py" in _get_response 
    185.     response = wrapped_callback(request, *callback_args, **callback_kwargs) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/views/generic/base.py" in view 
    68.    return self.dispatch(request, *args, **kwargs) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/views/generic/base.py" in dispatch 
    88.   return handler(request, *args, **kwargs) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/views/generic/edit.py" in post 
    185.    return self.form_invalid(form) 

File "/home/laptopguy/Documents/lineupNovember/lineup/views.py" in form_invalid 
    58.   return render(self.request, self.template_name, context) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/shortcuts.py" in render 
    30.  content = loader.render_to_string(template_name, context, request, using=using) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/template/loader.py" in render_to_string 
    68.  return template.render(context, request) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/template/backends/django.py" in render 
    64.   context = make_context(context, request, autoescape=self.backend.engine.autoescape) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/template/context.py" in make_context 
    267.    context.push(original_context) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/template/context.py" in push 
    59.   return ContextDict(self, *dicts, **kwargs) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/template/context.py" in __init__ 
    18.   super(ContextDict, self).__init__(*args, **kwargs) 

File "/home/laptopguy/Documents/lineupNovember/python3env/lib/python3.5/site-packages/django/template/response.py" in __iter__ 
    123.     'The response content must be rendered before it can be iterated over.' 

Exception Type: ContentNotRenderedError at /search/ 
Exception Value: The response content must be rendered before it can be iterated over. 

Answer 1

Die Zurückverfolgungs zeigt, dass das Problem in Ihrem form_invalid Methode. Sie erfassen das Ergebnis des Superklassenaufrufs als context und übergeben es an die Renderfunktion. Aber die Superklassenmethode gibt eine Antwort, keinen Kontext zurück - es hat bereits die Vorlage für Sie gerendert, Sie müssen es nur zurückgeben.

def form_invalid(self, form): 
    schWord = form.cleaned_data['search_word'] 
    messages.add_message(
     self.request, messages.WARNING, _('Please correct this...')) 
    return super(SearchFormView, self).form_invalid(form)