Django 1.9 check if email already exists

Question

My site is set up so there is no username (or rather user.username = user.email). Django has an error message if a user tries to input a username that is already in the data

Answer 1

You can override the clean_<INSERT_FIELD_HERE>() method on the UserForm to check against this particular case. It'd look something like this:

forms.py:

class UserForm(forms.ModelForm):
    class Meta:
        model = User
        fields = ('email',)

    def clean_email(self):
        # Get the email
        email = self.cleaned_data.get('email')

        # Check to see if any users already exist with this email as a username.
        try:
            match = User.objects.get(email=email)
        except User.DoesNotExist:
            # Unable to find a user, this is fine
            return email

        # A user was found with this as a username, raise an error.
        raise forms.ValidationError('This email address is already in use.')

class UserProfileForm(forms.ModelForm):
    class Meta:
        model = UserProfile
        fields = ('first_name', 'last_name', 'company', 'website', 'phone_number')

You can read more about cleaning specific fields in a form in the Django documentation about forms.

That said, I think you should look into creating a custom user model instead of treating your User Profile class as a wrapper for User.