Validate form field that include email or emails separated by 'token' kwargs, by default ',' a comma. Return a list [] of email(s). Check validity of the email(s) from django EmailField regex (work with 1.6)

comma_separated_email_field.py

from django import forms
from django.utils.translation import ugettext_lazy as _
from django.core import validators
from django.core.validators import EMPTY_VALUES
from django.forms.fields import Field

# Same as https://djangosnippets.org/snippets/3012/ but compatible with Django 1.6
class CommaSeparatedEmailField(Field):
    description = _(u"E-mail address(es)")

    def __init__(self, *args, **kwargs):
        self.token = kwargs.pop("token", ",")
        super(CommaSeparatedEmailField, self).__init__(*args, **kwargs)

    def to_python(self, value):
        if value in EMPTY_VALUES:
            return []

        value = [item.strip() for item in value.split(self.token) if item.strip()]

        return list(set(value))

    def clean(self, value):
        """
        Check that the field contains one or more 'comma-separated' emails
        and normalizes the data to a list of the email strings.
        """
        value = self.to_python(value)

        if value in EMPTY_VALUES and self.required:
            raise forms.ValidationError(_(u"This field is required."))

        for email in value:
            validators.validate_email(email)
        return value