Formset mixin

edit.py

class InlineFormsetMixin(SingleObjectTemplateResponseMixin, BaseFormsetMixin):
    object = None
    formset_link_field = None

    def get_formset_kwargs(self):
        """
        Gets the formset kwargs

        :returns: dict of kwargs
        """
        kwargs = {'initial': self.get_formset_initial()}
        if hasattr(self, 'get_formset_prefix'):
            kwargs.update({'prefix': self.get_formset_prefix()})

        if hasattr(self, 'get_object') and hasattr(self, 'get_queryset'):
            kwargs.update({'instance': self.get_object(queryset=self.get_queryset())})

        if self.request.method in ('POST', 'PUT'):
            kwargs.update({'files': self.request.FILES, 'data': self.request.POST})

        settings.DEBUG and logger.debug(u'InlineFormsetMixin::get_formset_kwargs() %s kwargs = %s', self.request.method,
                                        unicode(repr(kwargs), errors='replace'))
        return kwargs

    def get_formset(self, formset_class=None, data=None):
        """
        Gets the current formset instance

        :param formset_class: formset class
        :param data: data from request
        :returns: formset instance
        """
        #
        # if self._formset_instance:
        #     settings.DEBUG and logger.debug(u'InlineFormsetMixin::get_formset() already initialized.')
        #     return self._formset_instance

        formset_class = formset_class or self.get_formset_class()
        self._formset_instance = formset_class(**self.get_formset_kwargs())
        return self._formset_instance

    def get_formset_link_field(self):
        if self.formset_link_field:
            return self.formset_link_field
        raise ImproperlyConfigured(u'%s MUST implement a formset_link_field attribute !' % self.__class__.__name__)

    def form_valid(self, form=None, formset=None):
        """
        Form and Formset are valid : redirect if **NOT** continuable

        :param form: current form
        :type form: Form
        :param formset: current formset
        :type formset: Formset
        :returns: tuple (saved object, list of formset objects)
        """
        settings.DEBUG and logger.debug(u'InlineFormsetMixin::form_valid() form and formset are valid !')
        if hasattr(self, 'get_object') and hasattr(self, 'get_queryset'):
            self.object = self.get_object(self.get_queryset())
        # Gets the form instance
        form = form or self.get_form()
        # # Loads the changed data
        changed_data = form.changed_data

        self.object = form.save(commit=True)
        # Gets the formset instance
        formset = formset or getattr(self, 'formset', None) or self.get_formset()
        settings.DEBUG and logger.debug(u'InlineFormsetMixin::form_valid() form.instance= *%s*'
                                        u'\nform.changed_data = %s', form.instance, changed_data)
        linked_instance_list = []
        formset_link_field = self.get_formset_link_field()
        for formset_form in formset.forms:
            if formset_form.has_changed() and formset_form.is_valid():
                if 'DELETE' in formset_form.changed_data:
                    formset_form.instance.delete()
                    continue
                linked_instance = formset_form.save(commit=False)
                try:
                    if hasattr(linked_instance, formset_link_field):
                        setattr(linked_instance, formset_link_field, self.object)
                        linked_instance.save()  # Save / commit instance !
                except Exception as e:
                    logger.warning(u'InlineFormsetMixin::form_valid() Unable to save formset form instance : %s', e)
                linked_instance_list.append(linked_instance)

        # Redirecting to view
        url = self._get_continuable_success_url()
        settings.DEBUG and logger.debug(u'InlineFormsetMixin::form_valid() '
                                        u'object = %s / linked_instance_list = %s\nurl = %s',
                                        self.object, unicode(repr(linked_instance_list), errors='ignore'), url)
        return redirect(url)

    def form_invalid(self, form=None, formset=None):
        """
        Action to perform is form is invalid

        :param form: parent form
        :param formset: formset
        :returns: current view with error messages
        """
        form = form or self.get_form()
        # formset = formset or self.get_formset()

        return super(InlineFormsetMixin, self).form_invalid(form)