Django：无法验证UserCreationForm

Question

Below is the content of my forms.py

from django import forms
from django.contrib.auth.forms import UserCreationForm
from django.contrib.auth.models import User

class RegistrationForm(UserCreationForm):

    email = forms.EmailField(required=True)
    first_name = forms.CharField(max_length=20, required=True)
    last_name = forms.CharField(max_length=20, required=True)

    class Meta:
        model = User
        fields = ('username', 'email', 'password1', 'password2', 'first_name', 'last_name')

        def save(self, commit=True):
            user = super(UserCreationForm, self).save(commit=False)
            user.email = self.cleaned_data['email']
            user.first_name = self.cleaned_data['first_name']
            user.last_name = self.cleaned_data['last_name']
#validation of email id----------
            email1 = user.email
            (fisrt, second,) = email1.split("@")
            (domain, exn,) = second.split(".")
            if not domain == "tmail":
                raise forms.ValidationError("Domain must be 'tmail'")

            if commit:
                user.save()
            return user

I am able to print form (including fields email, first_name & last_name) & register the user successfully only issue I have is, Its not performing the validation step. (code below the "#validation of email id----------") Even if the domain is other than "tmail" it is accepting it without raising any validation error & then registering the user into database. Please help & let me know in case you need more info.

Answer 1

It is too late to validate the email in the save() method. Django lets you validate individual fields by defining a method clean_<fieldname> . This will be called when the form is validated.

def clean_email(self):
    email = self.cleaned_data['email']
    (first, second,) = email1.split("@")
    (domain, exn,) = second.split(".")
    if domain != "tmail":
        raise forms.ValidationError("Domain must be 'tmail'")
    return email 

See the docs on cleaning a specific field attribute for more info.

Answer 2

Why are you doing validation in save? All validations must happen before save, such that if any exception does comes in save it is most probably bug in your code. Forms specifically have 'clean' methods especially for this purpose. For specific field validation, you can use "clean_{field_name}". Though if your validation depends on multiple fields, you need to use "clean" method.