source: products/quintagroup.plonecaptchas/trunk/quintagroup/plonecaptchas/browser/register.py

from zope.formlib import form
from zope.interface import Interface
from plone.app.users.browser.register import RegistrationForm

from quintagroup.formlib.captcha import Captcha
from quintagroup.formlib.captcha import CaptchaWidget

from quintagroup.plonecaptchas import ProductMessageFactory as _


class CaptchaSchema(Interface):
    captcha = Captcha(
        title=_(u'Type the code'),
        description=_(u'Type the code from the picture shown below.'))


class CaptchaRegistrationForm(RegistrationForm):
    """Registration form with captacha."""

    @property
    def form_fields(self):
        """Add captcha field to form_fields."""
        ffields = super(CaptchaRegistrationForm, self).form_fields
        if len(ffields):
            ffields = ffields + form.Fields(CaptchaSchema)
            # XXX: Because of raising ConfigurationConflictError when include
            # configure.zcml slug of quintagroup.formlib.captcha, we must
            # explicytly define custom CaptchaWidget widget for Captcha field.
            ffields["captcha"].custom_widget = CaptchaWidget
        return ffields