django-fields-history 0.1.3

Store model fields history

django-fields-history

A Django app that track history changes in model fields.

Important note: currently only one implementation of FieldsHistory is supported and it's with django.contrib.postgres.fields.JSONField which is JSONB under the hood. So only postgresql as database is supported

Similar projects:

• django-reversion
• django-simple-history
• django-field-history

Main difference that those libraries keep track of changes, and this library tracks the history change.

Simple explanation:

from field_history.trackers import FieldsHistoryTracker

class SimpleModel(models.Model):
    field = models.CharField(max_length=50)

    field_history = FieldsHistoryTracker(fields=['field'])

obj = SimpleModel.objects.create(field='value')
assert not obj.get_field_history()


obj.field = "new_value"
obj.save()
assert obj.get_field_history()
assert obj.get_field_history()[0].value == "value"

QuickStart

Install django-fields-history:

pip install django-fields-history

Add fields_history.postgres to INSTALLED_APPS (currently only postgres implementation is supported):

INSTALLED_APPS = [
    # rest of apps
    "fields_history.postgres",
]

And add trackers to your models and specify fields to track:

from field_history.trackers import FieldsHistoryTracker

class YourModel(models.Model):
    ...

    history_tracker = FieldsHistoryTracker(fields=["field1", "field2"])

And you are done.

Implementation

Every change of your fields field changes be tracked in fields_history.models.FieldsHistory in:

• fields_history.postgres - JSONB postgres field

One object per save if tracked fields has been changed.

Credits

Basically this project is implemented based on django-field-history which itself used django-model-utils.