Versions: add timestamp fields

This is to allow us to track the latest updated date.

readthedocs/builds/migrations/0029_add_time_fields.py

@@ -0,0 +1,24 @@
+# Generated by Django 2.2.16 on 2020-11-18 16:26
+
+from django.db import migrations
+import django_extensions.db.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('builds', '0028_add_delete_version_action'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='version',
+            name='created',
+            field=django_extensions.db.fields.CreationDateTimeField(auto_now_add=True, null=True, verbose_name='created'),
+        ),
+        migrations.AddField(
+            model_name='version',
+            name='modified',
+            field=django_extensions.db.fields.ModificationDateTimeField(auto_now=True, verbose_name='modified'),
+        ),
+    ]

readthedocs/builds/models.py

@@ -15,6 +15,7 @@
 from django.utils import timezone
 from django.utils.translation import ugettext
 from django.utils.translation import ugettext_lazy as _
+from django_extensions.db.fields import CreationDateTimeField
 from django_extensions.db.models import TimeStampedModel
 from jsonfield import JSONField
 from polymorphic.models import PolymorphicModel
@@ -88,10 +89,18 @@
 log = logging.getLogger(__name__)
 
 
-class Version(models.Model):
+class Version(TimeStampedModel):
 
     """Version of a ``Project``."""
 
+    # Overridden from TimeStampedModel just to allow null values.
+    # TODO: remove after deploy.
+    created = CreationDateTimeField(
+        _('created'),
+        null=True,
+        blank=True,
+    )
+
     project = models.ForeignKey(
         Project,
         verbose_name=_('Project'),