Add ignore_saving_historical_record_on_delete flag

docs/querying_history.rst

@@ -146,6 +146,20 @@ If you want to save a model without a historical record, you can use the followi
     poll.save_without_historical_record()
 
 
+Delete model without saving historical record
+---------------------------------------------
+
+If you have a model that will cause a large number of cascading deletions and 
+you don't wish to save history instances due to performance issues, you can
+set ``ignore_saving_historical_record_on_delete`` to ``True`` on ``HistoricalRecord``
+
+.. code-block:: python
+
+    class Poll(models.Model):
+        question = models.CharField(max_length=200)
+        history = HistoricalRecords(ignore_saving_historical_record_on_delete=True)
+
+
 Filtering data using a relationship to the model
 ------------------------------------------------
 

simple_history/models.py

@@ -74,6 +74,7 @@ def __init__(
         related_name=None,
         use_base_model_db=False,
         user_db_constraint=True,
+        ignore_saving_historical_record_on_delete=False,
     ):
         self.user_set_verbose_name = verbose_name
         self.user_related_name = user_related_name
@@ -92,6 +93,9 @@ def __init__(
         self.user_setter = history_user_setter
         self.related_name = related_name
         self.use_base_model_db = use_base_model_db
+        self.ignore_saving_historical_record_on_delete = (
+            ignore_saving_historical_record_on_delete
+        )
 
         if excluded_fields is None:
             excluded_fields = []
@@ -474,6 +478,8 @@ def post_delete(self, instance, using=None, **kwargs):
         if self.cascade_delete_history:
             manager = getattr(instance, self.manager_name)
             manager.using(using).all().delete()
+        elif getattr(self, "ignore_saving_historical_record_on_delete", False):
+            return
         else:
             self.create_historical_record(instance, "-", using=using)
 

simple_history/tests/models.py

@@ -147,6 +147,14 @@ class Choice(models.Model):
     votes = models.IntegerField()
 
 
+class ChoiceWithIgnoredHistoryOnDelete(models.Model):
+    poll = models.ForeignKey(Poll, on_delete=models.CASCADE)
+    choice = models.CharField(max_length=200)
+    votes = models.IntegerField()
+
+    history = HistoricalRecords(ignore_saving_historical_record_on_delete=True)
+
+
 register(Choice)
 
 

simple_history/tests/tests/test_models.py

@@ -42,6 +42,7 @@
     CharFieldChangeReasonModel,
     CharFieldFileModel,
     Choice,
+    ChoiceWithIgnoredHistoryOnDelete,
     City,
     ConcreteAttr,
     ConcreteExternal,
@@ -238,6 +239,21 @@ def test_cascade_delete_history(self):
         self.assertEqual(len(thames.history.all()), 1)
         self.assertEqual(len(nile.history.all()), 0)
 
+    def test_ignore_saving_historical_record_on_delete(self):
+        poll = Poll.objects.create(question="foo", pub_date=today)
+        choice_with_history = Choice.objects.create(poll=poll, choice="a", votes=1)
+        choice_without_deletion_history = ChoiceWithIgnoredHistoryOnDelete.objects.create(
+            poll=poll, choice="c", votes=1
+        )
+
+        self.assertEqual(len(choice_with_history.history.all()), 1)
+        self.assertEqual(len(choice_without_deletion_history.history.all()), 1)
+        poll.delete()
+        self.assertEqual(len(choice_with_history.history.all()), 2)
+        self.assertFalse(
+            choice_without_deletion_history.history.filter(history_type="-").exists()
+        )
+
     def test_save_without_historical_record(self):
         pizza_place = Restaurant.objects.create(name="Pizza Place", rating=3)
         pizza_place.rating = 4