from typing import Set # noqa from django.apps import apps from django.contrib.contenttypes.models import ContentType from ..utils.auth import has_perm from ..utils.autoupdate import inform_changed_data from ..utils.collection import Collection from .models import Item def listen_to_related_object_post_save(sender, instance, created, **kwargs): """ Receiver function to create agenda items. It is connected to the signal django.db.models.signals.post_save during app loading. Do not run caching and autoupdate if the instance as an attribute skip_autoupdate (regardless of its truthy or falsy conent). """ if hasattr(instance, 'get_agenda_title'): if created: # If the object is created, the related_object has to be sent again. Item.objects.create(content_object=instance) if not hasattr(instance, 'skip_autoupdate'): inform_changed_data(instance) elif not hasattr(instance, 'skip_autoupdate'): # If the object has changed, then also the agenda item has to be sent. inform_changed_data(instance.agenda_item) def listen_to_related_object_post_delete(sender, instance, **kwargs): """ Receiver function to delete agenda items. It is connected to the signal django.db.models.signals.post_delete during app loading. """ if hasattr(instance, 'get_agenda_title'): content_type = ContentType.objects.get_for_model(instance) try: # Attention: This delete() call is also necessary to remove # respective active list of speakers projector elements. Item.objects.get(object_id=instance.pk, content_type=content_type).delete() except Item.DoesNotExist: # Item does not exist so we do not have to delete it. pass def get_permission_change_data(sender, permissions, **kwargs): """ Yields all necessary collections if 'agenda.can_see' or 'agenda.can_see_hidden_items' permissions changes. """ agenda_app = apps.get_app_config(app_label='agenda') for permission in permissions: # There could be only one 'agenda.can_see' and then we want to return data. if (permission.content_type.app_label == agenda_app.label and permission.codename in ('can_see', 'can_see_hidden_items')): yield from agenda_app.get_startup_elements() break def required_users(sender, request_user, **kwargs): """ Returns all user ids that are displayed as speakers in any agenda item if request_user can see the agenda. This function may return an empty set. """ speakers = set() # type: Set[int] if has_perm(request_user, 'agenda.can_see'): for item_collection_element in Collection(Item.get_collection_string()).element_generator(): full_data = item_collection_element.get_full_data() speakers.update(speaker['user_id'] for speaker in full_data['speakers']) return speakers