prepare_inline_admin_formset.py

# Django 1.7


class InlineAdminFormsetMixin(object):
    inline_admin_formset_class = InlineAdminFormSet

    def get_inline_formsets(self, request, formsets, inline_instances,
                            obj=None):
        inline_admin_formsets = []
        for inline, formset in zip(inline_instances, formsets):
            fieldsets = list(inline.get_fieldsets(request, obj))
            readonly = list(inline.get_readonly_fields(request, obj))
            prepopulated = dict(inline.get_prepopulated_fields(request, obj))
            inline_admin_formset = self.inline_admin_formset_class(
                inline=inline, formset=formset, fieldsets=fieldsets,
                prepopulated_fields=prepopulated, readonly_fields=readonly,
                model_admin=self)
            inline_admin_formsets.append(inline_admin_formset)
        return inline_admin_formsets


class PrepareFormset(InlineAdminFormSet):
    _request = None
    _obj = None

    def __iter__(self):
        # if inline has prepare_form method
        func = getattr(self.opts, 'prepare_form', None)
        for form in super(PrepareFormset, self).__iter__():
            if func:
                func(form=form.form, request=self._request, obj=self._obj)
            yield form


class PrepareFormsetMixin(InlineAdminFormsetMixin):
    inline_admin_formset_class = PrepareFormset

    def get_inline_formsets(self, request, formsets, inline_instances,
                            obj=None):
        inline_admin_formsets = \
            super(PrepareFormsetMixin, self).get_inline_formsets(
                request, formsets, inline_instances, obj=obj)
        for fs in inline_admin_formsets:
            fs._request = request
            fs._obj = obj

            func = getattr(fs.opts, 'prepare_formset', None)
            if func:
                func(formset=fs.formset, request=request,
                     obj=obj)
        return inline_admin_formsets