For future use, also store who created each query and when (#486)

backend/items/migrations/0005_auto_20210708_1249.py

@@ -0,0 +1,28 @@
+# Generated by Django 2.0.13 on 2021-07-08 10:49
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+import django.utils.timezone
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ('items', '0004_semanticquery'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='semanticquery',
+            name='created',
+            field=models.DateTimeField(auto_now_add=True, default=django.utils.timezone.now),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name='semanticquery',
+            name='creator',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.SET_NULL, to=settings.AUTH_USER_MODEL),
+        ),
+    ]

backend/items/models.py

@@ -1,5 +1,6 @@
 from django.db import models
 from django.contrib.postgres.fields import JSONField
+from django.conf import settings
 
 from rdf.baseclasses import BaseCounter
 from .constants import ITEMS_NS, ITEMS_HISTORY_NS
@@ -16,6 +17,10 @@ class EditCounter(BaseCounter):
 class SemanticQuery(models.Model):
     label = models.CharField(blank=True, max_length=100)
     query = JSONField()
+    creator = models.ForeignKey(
+        settings.AUTH_USER_MODEL, null=True, on_delete=models.SET_NULL,
+    )
+    created = models.DateTimeField(auto_now_add=True)
 
     def __str__(self):
         return self.label or str(self.id)