Usage

django-bulk-tracker will emit a signal whenever you update, create, or delete a record in the database

django-bulk-tracker supports bulk operations:

• queryset.update()

• queryset.bulk_update()

• queryset.bulk_create()

• queryset.delete()

and single operations:

• create()

• save() # update and create

• delete()

all you need to do is to define your Model and inherit from:

from bulk_tracker.models import BulkTrackerModel

class Author(BulkTrackerModel):
first_name = models.CharField(max_length=200)
last_name = models.CharField(max_length=200)

OR if you have a custom queryset inherit from or Don’t want to support single-operation:

from bulk_tracker.managers import BulkTrackerQuerySet

class MyModelQuerySet(BulkTrackerQuerySet):
    def do_something_custom(self):
        pass

now you can listen to the signals post_update_signal, post_create_signal, post_delete_signal:

@receiver(post_update_signal, sender=MyModel)
def i_am_a_receiver_function(
    sender,
    objects: list[ModifiedObject[MyModel]],
    tracking_info_: TrackingInfo | None = None,
    **kwargs,
):
    do_stuff()

Hint

all signals have the same signature for consistency, and also in case you want to assign one function to listen to multiple signals

ModifiedObject is a very simple object, it contains 2 attributes: 1- instance this is your model instance after it has been updated, or created 2- changed_values is dict[str, Any] which contains the changed fields only in case of post_update_signal, in case of post_create_signal and post_delete_signal, changed_values will be an empty dict {}

Optionally you can pass tracking_info_ to your functions, as in:

from bulk_tracker.helper_objects import TrackingInfo

def a_function_that_updates_records():
    user = self.request.user
    MyModel.objects.filter(name='john').update(
        name='jack',
        tracking_info_=TrackingInfo(user=user, comment="Updated from a function", kwargs={'app-build':1.1.8}),
        )

Hint

tracking_info_ has a trailing underscore to avoid collision with your actual fields

you can use TrackingInfo to implement any kind of behavior like logging in your signal handlers and you need to capture more info about the operation that is happening.

For single operations as well

• create()

• save() # update and create

• delete()

to support we rely on the amazing library django-model-utils to track the model instances

1. do the above

2. you need to to inherit your model from BulkTrackerModel

3. add tracker = FieldTracker() to your model

as in

from bulk_tracker.models import BulkTrackerModel
from model_utils import FieldTracker


class MyModel(BulkTrackerModel):

    objects = MyModelQuerySet.as_manager() # MyModelManager() if you have
    tracker = FieldTracker()

Complete Example

# models.py
from bulk_tracker.models import BulkTrackerModel
from model_utils import FieldTracker

from myapp.managers import MyModelManager


class MyModel(BulkTrackerModel):
    first_field = models.CharField()
    second_field = models.CharField()

    objects = MyModelManager()
    tracker = FieldTracker()

# managers.py
from bulk_tracker.managers import BulkTrackerQuerySet # optional


class MyModelQuerySet(BulkTrackerQuerySet):
    pass


class MyModelManager(BulkTrackerManager.from_queryset(MyModelQuerySet)): # optional
    pass

# signal_handlers.py
from bulk_tracker.signals import post_update_signal
from bulk_tracker.helper_objects import ModifiedObject, TrackingInfo


@receiver(post_update_signal, sender=MyModel)
def i_am_a_receiver_function(
    sender,
    objects: list[ModifiedObject[MyModel]],
    tracking_info_: TrackingInfo | None = None,
    **kwargs,
):
    user = tracking_info_.user if tracking_info_ else None
    for modified_objects in modified_objects:
        if 'name' in modified_object.changed_values:
            log(f"field 'name' has changed by {user or ''}")
            notify_user()