init

backend/utils/models.py

@@ -0,0 +1,57 @@
+from django.db import models
+from django.utils import timezone
+
+class SoftDeleteQuerySet(models.QuerySet):
+    def delete(self):
+        return super().update(is_deleted=True, deleted_at=timezone.now())
+
+    def hard_delete(self):
+        return super().delete()
+
+    def alive(self):
+        return self.filter(is_deleted=False)
+
+    def dead(self):
+        return self.filter(is_deleted=True)
+
+class SoftDeleteManager(models.Manager):
+    def __init__(self, *args, **kwargs):
+        self.alive_only = kwargs.pop('alive_only', None)
+        super().__init__(*args, **kwargs)
+
+    def get_queryset(self):
+        if self.alive_only is True:
+            return SoftDeleteQuerySet(self.model).filter(is_deleted=False)
+        if self.alive_only is False:
+            return SoftDeleteQuerySet(self.model).filter(is_deleted=True)
+        if self.alive_only is None:
+            return SoftDeleteQuerySet(self.model)
+
+    def hard_delete(self):
+        return self.get_queryset().hard_delete()
+
+class BaseModel(models.Model):
+    created_at = models.DateTimeField(auto_now_add=True)
+    updated_at = models.DateTimeField(auto_now=True)
+    is_deleted = models.BooleanField(default=False)
+    deleted_at = models.DateTimeField(null=True, blank=True)
+
+    objects = SoftDeleteManager(alive_only=True)
+    all_objects = SoftDeleteManager(alive_only=None)
+    deleted_objects = SoftDeleteManager(alive_only=False)
+
+    class Meta:
+        abstract = True
+
+    def delete(self, using=None, keep_parents=False):
+        self.is_deleted = True
+        self.deleted_at = timezone.now()
+        self.save(using=using)
+
+    def hard_delete(self, using=None, keep_parents=False):
+        super().delete(using=using, keep_parents=keep_parents)
+
+    def restore(self):
+        self.is_deleted = False
+        self.deleted_at = None
+        self.save()