API: get changes since

[wolnelektury.git] / apps / api / models.py

diff --git a/apps/api/models.py b/apps/api/models.py
new file mode 100644 (file)
index 0000000..8858162
--- /dev/null
+++ b/apps/api/models.py
@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+# This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
+# Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
+#
+from django.db import models
+from django.db.models.signals import pre_delete
+
+from catalogue.models import Book, Tag
+
+
+class Deleted(models.Model):
+    object_id = models.IntegerField()
+    type = models.CharField(max_length="50", db_index=True)
+    created_at = models.DateTimeField(editable=False, db_index=True)
+    deleted_at = models.DateTimeField(auto_now_add=True, db_index=True)
+
+    class Meta:
+        unique_together = (('type', 'object_id'),)
+
+
+
+def _pre_delete_handler(sender, instance, **kwargs):
+    """ save deleted objects for change history purposes """
+
+    if sender in (Book, Tag):
+        Deleted.objects.create(type=sender.__name__, object_id=instance.id, created_at=instance.created_at)
+pre_delete.connect(_pre_delete_handler)