How to check validation on two fields in a form? - django

Question

Need to add an image to the form either by entering a link to the image, or upload a file from your computer. If no options were entered when the form was submitted, or both options were entered, an error message should be displayed. And after successful loading, you should get to the image page.
models.py:
class Picture(models.Model):
url = models.URLField(blank=True, verbose_name='Ссылка на изображение')
image = models.ImageField(upload_to='pictures/%Y/%m/%d', width_field='image_width', height_field='image_height',
blank=True, verbose_name='Изображение')
image_width = models.IntegerField(default=0, blank=True, verbose_name='Ширина изображения')
image_height = models.IntegerField(default=0, blank=True, verbose_name='Высота изображения')
is_active = models.BooleanField(default=True, verbose_name='Актуальность изображения')
created = models.DateField(blank=True, null=True, default=timezone.now, verbose_name='Дата создания записи')
updated = models.DateField(blank=True, null=True, default=timezone.now, verbose_name='Дата ред-ия записи')
views.py:
def add_picture(request):
picture = Picture.objects.filter(is_active=True)
if request.method == 'POST':
form = PictureCreateForm(data=request.POST, files=request.FILES)
if form.is_valid():
form.save()
return render(request, 'add_picture.html', locals())
else:
messages.error(request, 'Ошибка, проверьте данные')
else:
form = PictureCreateForm()
return render(request, 'add_picture.html', locals())
forms.py: Here you need to define a method clean
class PictureCreateForm(forms.ModelForm):
class Meta:
model = Picture
fields = ('url', 'image')
def clean(self):
cd = self.cleaned_data
if cd['url'] and cd['image']:
raise forms.ValidationError('Ошибка!')
if not cd['url'] and not cd['image']:
raise forms.ValidationError('Ошибка!')
return cd
urls.py:
urlpatterns = [
path('', views.home, name='home'),
path('add_picture/', views.add_picture, name='add_picture'),
path('picture_detail/<int:id>/', views.picture_detail, name='picture_detail'),
]

Answer 1

You can make use of the clean(...) method of forms.ModelForm as
class PictureCreateForm(forms.ModelForm):
class Meta:
model = Picture
fields = ('url', 'image')
def clean(self):
cleaned_data = super().clean()
url = cleaned_data.get("url")
image = cleaned_data.get("url")
# do your logic here
# atlast
return cleaned_data