Unique users per site

[Manosucias]

Hi

I'm deploying a multi site based shop and I need different users per site: End users needs to register on every site as independent stores.

I'd created a custom auth backend based in the original one that is handling the Auth part pretty well, but I have a problem in the registration. As the satchmo_store/accounts application check the email addres as unique, I need to override/modify the clean_email method inside the RegistrationForm. The only thing I need is a dummy site ID check but I don0t know how to do it without modify the Satchmo/Accounts code or fork the whole application. Can I do any kind of MonkeyPatching?

here is the Custom Auth backend:

class EmailSiteBackend(ModelBackend):

    """Authenticate using email only"""

    def authenticate(self, username=None, password=None):

        #If username is an email address, then try to pull it up

        if email_re.search(username):

            user = User.objects.filter(email__iexact=username)

            if user.count() > 0:

                user = user[0]

                if user.get_profile().site == Site.objects.get_current():

                    if user.check_password(password):

                        return user

                

        return None

            

and what I need to modify is the:

satchmo_store/accounts/forms.py:

class RegistrationForm(forms.Form):

......

      def clean_email(self):

        """Prevent account hijacking by disallowing duplicate emails."""
        email = self.cleaned_data.get('email', None)
        if email and User.objects.filter(email__iexact=email).count() > 0:
            raise forms.ValidationError(
                ugettext("That email address is already in use."))
        return email

to add the site check somehow