Add a model for package

src/website/shared/migrations/0049_nixpackage_nixderivation_package.py

@@ -0,0 +1,44 @@
+from django.db import migrations, models, transaction
+import django.db.models.deletion
+
+def populate_package_field(apps, schema_editor):
+    NixPackage = apps.get_model('shared', 'NixPackage')
+    NixDerivation = apps.get_model('shared', 'NixDerivation')
+
+    with transaction.atomic():
+        for derivation in NixDerivation.objects.all():
+            package, _ = NixPackage.objects.get_or_create(name=derivation.attribute)
+            derivation.package = package
+            derivation.save()
+
+def reverse_populate_package_field(apps, schema_editor):
+    NixDerivation = apps.get_model('shared', 'NixDerivation')
+    NixDerivation.objects.update(package=None)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('shared', '0048_remove_attribute_suffix'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='NixPackage',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=255, unique=True)),
+            ],
+        ),
+        migrations.AddField(
+            model_name='nixderivation',
+            name='package',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, to='shared.nixpackage'),
+        ),
+        migrations.RunPython(populate_package_field, reverse_populate_package_field),
+        migrations.AlterField(
+            model_name='nixderivation',
+            name='package',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='shared.nixpackage'),
+        ),
+    ]

src/website/shared/models/nix_evaluation.py

@@ -270,6 +270,13 @@ class Meta:  # type: ignore[override]
         unique_together = ("channel", "commit_sha1")
 
 
+class NixPackage(models.Model):
+    name = models.CharField(max_length=255, unique=True)
+
+    def __str__(self) -> str:
+        return self.name
+
+
 class NixDerivation(models.Model):
     """
     This represents a Nix derivation "evaluated",
@@ -279,6 +286,7 @@ class NixDerivation(models.Model):
     - parsing the .drv
     """
 
+    package = models.ForeignKey(NixPackage, on_delete=models.CASCADE, null=True)
     attribute = models.CharField(max_length=255)
     derivation_path = models.CharField(max_length=255)
     dependencies = models.ManyToManyField(NixDerivationOutput)