Django - How to specify which field a validation fails on?

Question

I have this model I\'m showing in the admin page:

class Dog(models.Model):
    bark_volume = models.DecimalField(...
    unladen_speed = models.DecimalField(...
         


        

Answer 1

Use a clean_ method that is specific to the field:

class DogForm(forms.ModelForm):
    class Meta:
        model = Dog

    def clean_bark_volume(self):
        if self.cleaned_data['bark_volume'] < 5:
            raise ValidationError("must be louder!")

See the clean part of the Form Validation page. Also, make sure to use cleaned_data instead of the form field itself; the latter may have old data. Finally, do this on the form and not the model.