Apkawa / django-snapshot-field

Snapshot model to field

Project for merging different file types, as example easy thumbnail image and unpacking archive in one field

Installation

pip install django-snapshot-field

or from git

pip install -e git+https://githib.com/Apkawa/django-snapshot-field.git#egg=django-snapshot-field

Django and python version compatibles

Python Django	3.7	3.8	3.9	3.10
2.2	✔️	✔️	✔️	✔️
3.2	✔️	✔️	✔️	✔️
4.0	❌	✔️	✔️	✔️

Usage

from django.db import models
from snapshot_field.fields import SnapshotModelField

class Example(models.Model):
    name = models.CharField(max_length=20)

class ExampleReference(models.Model):
    name = models.CharField(max_length=20)
    ref = models.ForeignKey(Example)


class ExampleSnapshotModel(models.Model):
    snapshot = SnapshotModelField(null=True)
    snapshot_refs = SnapshotModelField(
        ['tests.Example', ['ExampleReference', {'fields': ['name', 'ref'], 'refs': ['ref']}]]
    )

    
obj = Example.objects.create(name='test_name')
obj_ref = ExampleReference.objects.create(name='refname', ref=obj)

snap = ExampleSnapshotModel.objects.create(snapshot=obj, snapshot_refs=obj_ref)

assert snap.snapshot.name == obj.name
assert snap.snapshot_refs.name == obj_ref.name
assert snap.snapshot_refs.ref.name == obj.name

obj.delete()
obj_ref.delete()
snap.refresh_from_db()

assert snap.snapshot.name == obj.name
assert snap.snapshot_refs.name == obj_ref.name
assert snap.snapshot_refs.ref.name == obj.name