CODEWITHSUNDEEP
pythondjangodjango-templates
Jamgreen
Jamgreen

Reputation: 11039

Django messages not working

I am trying to use Django's messages framework.

I've done exactly as told in https://docs.djangoproject.com/en/dev/ref/contrib/messages/#enabling-messages

I add messages by messages.success(self.request, 'Updated.') but no messages is shown. {% if messages %} evaluates as always false.

If I print {{ messages }} I get <django.contrib.messages.storage.fallback.FallbackStorage object at 0x7fb701c47b70>.

What can be wrong?

My middlewares

MIDDLEWARE_CLASSES = (
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
)

My template context processors

TEMPLATE_CONTEXT_PROCESSORS = [
    "django.contrib.auth.context_processors.auth",
    "django.template.context_processors.debug",
    "django.template.context_processors.i18n",
    "django.core.context_processors.request",
    "django.template.context_processors.media",
    "django.template.context_processors.static",
    "django.template.context_processors.tz",
    "django.contrib.messages.context_processors.messages"
]

My installed apps

INSTALLED_APPS = (
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'django.contrib.humanize',
)

Edit

class ItemUpdateView(LoginRequiredMixin, UpdateView):
    model = Item
    context_object_name = 'item'
    form_class = ItemForm

    def get_form_kwargs(self):
        kwargs = super(ItemUpdateView, self).get_form_kwargs()
        kwargs["user"] = self.request.user
        return kwargs

    def form_valid(self, form):
        with transaction.atomic(), reversion.create_revision():
            self.object = form.save()
            reversion.set_user(self.request.user)
            reversion.set_comment("Updating")
        messages.success(self.request, "Updated")
        return HttpResponseRedirect(self.get_success_url())

    def get_success_url(self):
        return self.object.get_update_url()

Edit 2

{% if messages %}
    <ul class="messages">
        {% for message in messages %}
            <li{% if message.tags %} class="{{ message.tags }}"{% endif %}>
                {% if message.level == DEFAULT_MESSAGE_LEVELS.ERROR %}Important: {% endif %}
                {{ message }}
            </li>
        {% endfor %}
    </ul>
{% else %}
    no messages
{% endif %}

Edit 3

This is a big mystery for me.

It doesn't add the message if I use

def form_valid(self, form):
    self.object = form.save()
    messages.success(self.request, "Updated")
    return HttpResponseRedirect(self.get_success_url())

but it does add the message if I use

def dispatch(self, request, *args, **kwargs):
    messages.success(request, 'Updated.')
    return super(ItemUpdateView, self).dispatch(request, *args, **kwargs)

Upvotes: 3

Views: 5298

Answers (2)

user2254991
user2254991

Reputation: 13

Posting this to help future users.

To resolve this issue, you must add a call to super() in the form_valid function:

def form_valid(self, form):
    super().form_valid(form) # if Python 3, else super(ItemUpdateView, self).form_valid(form)
    ...

Upvotes: 0

Ivan
Ivan

Reputation: 1507

You are not seeing your messages in the template because form_valid returns an HttpResponse, which drops the request object on the floor.

Note how your solution does pass the request object forward.

return super(ItemUpdateView, self).dispatch(request, *args, **kwargs)

What you could do to get around this is to make sure you always get the messages within the view and pass it as a context object. Then the response method won't matter.

from django.contrib import messages

class Homepage(View):
    template_name = 'index.html'
    def get(request):
        return render(request, self.template_name, {
            'messages': messages.get_messages(request)
        })

    def post(request):
        return HttpResponseRedirect('/home/')

Upvotes: 2

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