move first / last cms plugin context menu

cms_plugins.py

# add to your normal cms_plugins.py whateverplugin

class DemoPlugin(CMSPluginBase):
    
    model = Demo
    ...
  
    def get_plugin_urls(self):
        return [
            url(r'^plugin_move_first/$', self.plugin_move_first, name='cmsplugin_move_first'),
            url(r'^plugin_move_last/$', self.plugin_move_last, name='cmsplugin_move_last'),
        ]

    @classmethod
    def get_extra_global_plugin_menu_items(cls, request, plugin):
        return [
            PluginMenuItem(
                _("Move to first position"),
                reverse("admin:cmsplugin_move_first"),
                data={'plugin_id': plugin.pk, 'csrfmiddlewaretoken': get_token(request)},
            ),
            PluginMenuItem(
                _("Move to last position"),
                reverse("admin:cmsplugin_move_last"),
                data={'plugin_id': plugin.pk, 'csrfmiddlewaretoken': get_token(request)},
            )
        ]

    def plugin_move_first(self, request):
        return self._plugin_move_to(request, 'first')

    def plugin_move_last(self, request):
        return self._plugin_move_to(request, 'last')

    def _plugin_move_to(self, request, position='first'):
        if not request.user.is_staff:
            return HttpResponseForbidden("not enough privileges")
        if not 'plugin_id' in request.POST:
            return HttpResponseBadRequest("plugin_id POST parameter missing.")
        plugin = None
        if 'plugin_id' in request.POST:
            pk = request.POST['plugin_id']
            try:
                plugin = CMSPlugin.objects.get(pk=pk)
            except CMSPlugin.DoesNotExist:
                return HttpResponseBadRequest("plugin with id %s not found." % pk)
        # do it!
        base_qs = CMSPlugin.objects.filter(
            placeholder=plugin.placeholder,
            parent=plugin.parent,
        )
        old_position = plugin.position
        if position == 'first':
            new_position = 0
        else:
            new_position = base_qs.count() - 1
        if new_position == old_position:
            pass
        if new_position > old_position:
            update_qs = base_qs.filter(position__lte=new_position, position__gt=old_position)
            update_qs.update(**{'position': F('position') - 1})
        if new_position < old_position:
            update_qs = base_qs.filter(position__gte=new_position, position__lt=old_position)
            update_qs.update(**{'position': F('position') + 1})
        plugin.position = new_position
        plugin.save()
        return HttpResponse('ok')

when working with Treebeard, you should use their API to do "low-level" stuff. Presumably this method is your friend:
https://django-treebeard.readthedocs.io/en/latest/api.html#treebeard.models.Node.move

hm. the treebeard does the tree, but as far as I see, the cms uses only position, for sorting on each level?

https://github.com/divio/django-cms/blob/develop/cms/admin/placeholderadmin.py#L932
and here https://github.com/divio/django-cms/blob/develop/cms/utils/plugins.py#L304, as in the cms admin and utils methods for ordering?

...as mentioned, it already works...but sure, treebeard and position will not be in sync (but this happens all the time anyway, for example when sorting by hand with drag and drop, in structure mode...)