Zapisywanie zalogowanego użytkownika django

Question

Witam. Robię sobie ostatnio aplikację, w której zalogowany użytkownik może tworzyć ankiety, przeglądać zrobione ankiety, itd. Wszystko działało ok, do momentu w którym stwierdziłem, że chcę mieć dynamiczne formy. Nie byłem pewny jak to zrobić, ostatecznie zrobiłem coś takiego:

forms.py

class CreateChoiceForm(forms.ModelForm):

    choice_0 = forms.CharField(required=True)
    choice_1 = forms.CharField(required=True)

    class Meta:
        model = Question
        fields = ['question_text']

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        choice = Choice.objects.filter(
            question=self.instance
        )
        for i in range(len(choice) + 1):
            field_name = 'choice_%s' % (i,)
            self.fields[field_name] = forms.CharField(required=False)
            try:
                self.initial[field_name] = choice[i].choice
            except IndexError:
                self.initial[field_name] = ""
            field_name = 'choice_%s' % (i+1,)
            self.fields[field_name] = forms.CharField(required=False)

    def save(self, commit=True):
        question = self.instance
        question.question_text = self.cleaned_data['question_text']
        question.choice_set.all().delete
        question.save()
        for i in range(2):
            choice = self.cleaned_data['choice_%i' % (i)]
            Choice.objects.create(question=question, choice_text=choice)

    def get_interest_fields(self):
        for field_name in self.fields:
            if field_name.startswith('choice_'):
                yield self[field_name]

Problem w tym, że teraz kiedy próbuję zatwierdzić wypełnione formularze na stronie to pojawia się ten błąd:

Environment:


Request Method: POST
Request URL: http://127.0.0.1:8000/polls/createPoll/

Django Version: 2.2.5
Python Version: 3.6.10
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'bootstrap3',
 'pollapp']
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']



Traceback:

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\backends\utils.py" in _execute
  84.                 return self.cursor.execute(sql, params)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\backends\sqlite3\base.py" in execute
  383.         return Database.Cursor.execute(self, query, params)

The above exception (NOT NULL constraint failed: pollapp_question.author_id) was the direct cause of the following exception:

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\core\handlers\exception.py" in inner
  34.             response = get_response(request)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\core\handlers\base.py" in _get_response
  115.                 response = self.process_exception_by_middleware(e, request)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\core\handlers\base.py" in _get_response
  113.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\views\generic\base.py" in view
  71.             return self.dispatch(request, *args, **kwargs)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\contrib\auth\mixins.py" in dispatch
  52.         return super().dispatch(request, *args, **kwargs)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\views\generic\base.py" in dispatch
  97.         return handler(request, *args, **kwargs)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\views\generic\edit.py" in post
  172.         return super().post(request, *args, **kwargs)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\views\generic\edit.py" in post
  142.             return self.form_valid(form)

File "H:\conda\INZ\pollapp\views.py" in form_valid
  71.         poll = form.save()

File "H:\conda\INZ\pollapp\forms.py" in save
  51.         question.save()

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\base.py" in save
  741.                        force_update=force_update, update_fields=update_fields)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\base.py" in save_base
  779.                 force_update, using, update_fields,

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\base.py" in _save_table
  870.             result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\base.py" in _do_insert
  908.                                using=using, raw=raw)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\manager.py" in manager_method
  82.                 return getattr(self.get_queryset(), name)(*args, **kwargs)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\query.py" in _insert
  1186.         return query.get_compiler(using=using).execute_sql(return_id)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\sql\compiler.py" in execute_sql
  1335.                 cursor.execute(sql, params)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\backends\utils.py" in execute
  99.             return super().execute(sql, params)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\backends\utils.py" in execute
  67.         return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\backends\utils.py" in _execute_with_wrappers
  76.         return executor(sql, params, many, context)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\backends\utils.py" in _execute
  84.                 return self.cursor.execute(sql, params)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\utils.py" in __exit__
  89.                 raise dj_exc_value.with_traceback(traceback) from exc_value

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\backends\utils.py" in _execute
  84.                 return self.cursor.execute(sql, params)

File "C:\Users\MaineKomputere\Anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\backends\sqlite3\base.py" in execute
  383.         return Database.Cursor.execute(self, query, params)

Exception Type: IntegrityError at /polls/createPoll/
Exception Value: NOT NULL constraint failed: pollapp_question.author_id

Tutaj reszta kodu:

models.py

from django.db import models
from django.utils import timezone
import datetime
from django.contrib import auth
# Create your models here.

User = auth.get_user_model()

class Question(models.Model):
    question_text = models.CharField(max_length=200)
    author = models.ForeignKey(User, on_delete=models.CASCADE, null=False)


    def __str__(self):
        return self.question_text

class Choice(models.Model):
    question = models.ForeignKey(Question, on_delete=models.CASCADE)
    choice_text = models.CharField(max_length=200)
    votes = models.IntegerField(default=0)
    def __str__(self):
        return self.choice_text

class User(auth.models.User, auth.models.PermissionsMixin):

    def __str__(self):
        return "@{}".format(self.username)

views.py

class CreatePoll(LoginRequiredMixin, generic.CreateView):
    form_class = forms.CreateChoiceForm
    template_name = 'polls/createPoll.html'
    success_url = reverse_lazy('pollapp:index')

    def form_valid(self, form):
        poll = form.save()
        poll.author = self.request.user
        poll.save()
        return super().form_valid(form)

    def get_form(self, form_class=None):
        form = super().get_form(form_class)
        form.request = self.request
        return form

    def get_success_url(self):
        return reverse('pollapp:myPolls', kwargs={'pk': self.object.pk})

Zmiana

author = models.ForeignKey(User, on_delete=models.CASCADE, null=False)

na

author = models.ForeignKey(User, on_delete=models.CASCADE, null=True)

niewiele daje. Wtedy pojawia się błąd:

Exception Value: 'NoneType' object has no attribute 'author' django

No i nie za bardzo wiem co teraz robić. Bardzo prosiłbym o pomoc w rozwiązaniu tego problemu, bo trochę stanąłem w martwym punkcie.

Answer 1

Strzelam: czy nie zabrakło aby pola na autora w Twoim formularzu?

Alternatywnie, możesz przed zapisaniem w bazie dodać do obiektu:

question = form.save(commit=False)
question.author = self.request.user
question.save()

Comments

Zanim zacząłem się bawić w dynamiczny formularz to nie potrzebowałem pola author w formularzu (przynajmiej tak mi się wydaje ;P) i działało. Zresztą i tak dodałem, żeby sprawdzić, czy zadziała i dalej jest ten sam błąd. Właśnie w kodzie mam zapisane to co napisałeś w metodzie form_valid(), wygląda to u mnie tak:

    def form_valid(self, form):
        poll = form.save(commit=False)
        poll.author = self.request.user
        poll.save()
        return super().form_valid(form)

 

---

Wydaje mi się, że w tym momencie wywołanie `super().form_valid(form)` już za bardzo nie ma sensu (bo w końcu niezależnie spróbuje drugi raz stworzyć obiekt bazodanowy).

---

W sumie racja, to pozostałość po starej wersji, zapomniałem to usunąć. Jednak usunięcie nie naprawia problemu :(

---

To pokaż proszę aktualny kod.

---

forms.py

class CreateChoiceForm(forms.ModelForm):

    choice_0 = forms.CharField(required=True)
    choice_1 = forms.CharField(required=True)

    class Meta:
        model = Question
        fields = ['question_text', 'author']

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        choice = Choice.objects.filter(
            question=self.instance
        )
        for i in range(len(choice) + 1):
            field_name = 'choice_%s' % (i,)
            self.fields[field_name] = forms.CharField(required=False)
            try:
                self.initial[field_name] = choice[i].choice
            except IndexError:
                self.initial[field_name] = ""
            field_name = 'choice_%s' % (i+1,)
            self.fields[field_name] = forms.CharField(required=False)

    def save(self, commit=True):
        question = self.instance
        question.question_text = self.cleaned_data['question_text']
        question.choice_set.all().delete
        question.save()
        for i in range(2):
            choice = self.cleaned_data['choice_%i' % (i)]
            Choice.objects.create(question=question, choice_text=choice)

    def get_interest_fields(self):
        for field_name in self.fields:
            if field_name.startswith('choice_'):
                yield self[field_name]

views.py

class CreatePoll(LoginRequiredMixin, generic.CreateView):
    form_class = forms.CreateChoiceForm
    template_name = 'polls/createPoll.html'
    success_url = reverse_lazy('pollapp:index')

    def form_valid(self, form):
        poll = form.save(commit=False)
        poll.author = self.request.user
        poll.save()


    def get_form(self, form_class=None):
        form = super().get_form(form_class)
        form.request = self.request
        return form

    def get_success_url(self):
        return reverse('pollapp:myPolls', kwargs={'pk': self.object.pk})

models.py

from django.db import models
from django.utils import timezone
import datetime
from django.contrib import auth
# Create your models here.

User = auth.get_user_model()

class Question(models.Model):
    question_text = models.CharField(max_length=200)
    author = models.ForeignKey(User, on_delete=models.CASCADE, null=False)


    def __str__(self):
        return self.question_text

class Choice(models.Model):
    question = models.ForeignKey(Question, on_delete=models.CASCADE)
    choice_text = models.CharField(max_length=200)
    votes = models.IntegerField(default=0)
    def __str__(self):
        return self.choice_text

class User(auth.models.User, auth.models.PermissionsMixin):

    def __str__(self):
        return "@{}".format(self.username)

urls.py

from django.contrib import admin
from django.urls import path, include
from django.contrib.auth import views as auth_views
from . import views

app_name = 'pollapp'
urlpatterns = [
    path('', views.IndexView.as_view(), name='index'),
    path('createdPolls/', views.ListView.as_view(), name='createdPolls'),
    path('<int:pk>/', views.DetailView.as_view(), name='detail'),
    path('<int:pk>/results/', views.ResultsView.as_view(), name='results'),
    path('<int:question_id>/vote/', views.vote, name='vote'),
    path('login/', auth_views.LoginView.as_view(template_name='registration/login.html'), name='login'),
    path('logout/', auth_views.LogoutView.as_view(), name='logout'),
    path('signup/', views.SignUp.as_view(), name='signup'),
    path('createPoll/', views.CreatePoll.as_view(), name='createPoll'),
    path('<int:pk>/choice', views.createChoice, name='createChoice'),
    path('userPolls/', views.UserPolls.as_view(), name='userPolls'),
]

To chyba wszystko co potrzebne.

---

...chwila, dopiero teraz zauważyłem.

poll = form.save(commit=False)

Fajnie że to zrobiłeś, ale...

    def save(self, commit=True):
        question = self.instance
        question.question_text = self.cleaned_data['question_text']
        question.choice_set.all().delete
        question.save()
        for i in range(2):
            choice = self.cleaned_data['choice_%i' % (i)]
            Choice.objects.create(question=question, choice_text=choice)

Co z tego, skoro napisałeś własną implementację save() która kompletnie ignoruje argument commit? :P

A skoro masz kompletnie własny save(), to w ogóle nie rozumiem gdzie masz problem, skoro możesz po prostu przekazać `author` do formularza i ustawić go w save().

---

O kurcze faktycznie :D

Dzięki za pomoc, sam bym pewnie tego nie zauważył ;P

Poniżej zostawiam kod, który działa, w razie jakby ktoś szukał odpowiedzi.

views.py

class CreatePoll(LoginRequiredMixin, generic.CreateView):
    form_class = forms.CreateChoiceForm
    template_name = 'polls/createPoll.html'
    success_url = reverse_lazy('pollapp:index')

    def get_form_kwargs(self):
        kwargs = super(CreatePoll, self).get_form_kwargs()
        kwargs.update({'request': self.request})
        return kwargs

    def get_form(self, form_class=None):
        form = super().get_form(form_class)
        form.request = self.request
        return form

    def get_success_url(self):
        # return reverse('pollapp:myPolls', kwargs={'pk': self.object.pk})
        return reverse('pollapp:index')

forms.py

class CreateChoiceForm(forms.ModelForm):

    choice_0 = forms.CharField(required=True)
    choice_1 = forms.CharField(required=True)

    class Meta:
        model = Question
        fields = ['question_text',]

    def __init__(self, *args, **kwargs):
        self.request = kwargs.pop('request')
        super(CreateChoiceForm, self).__init__(*args, **kwargs)

        choice = Choice.objects.filter(
            question=self.instance
        )
        for i in range(len(choice) + 1):
            field_name = 'choice_%s' % (i,)
            self.fields[field_name] = forms.CharField(required=False)
            try:
                self.initial[field_name] = choice[i].choice
            except IndexError:
                self.initial[field_name] = ""
            field_name = 'choice_%s' % (i+1,)
            self.fields[field_name] = forms.CharField(required=False)

    def save(self, commit=True):
        question = self.instance
        question.question_text = self.cleaned_data['question_text']
        question.author = self.request.user
        question.choice_set.all().delete
        question.save()
        for i in range(2):
            choice = self.cleaned_data['choice_%i' % (i)]
            Choice.objects.create(question=question, choice_text=choice)

    def get_interest_fields(self):
        for field_name in self.fields:
            if field_name.startswith('choice_'):
                yield self[field_name]