Add metadata model & migration

src/documents/migrations/1036_add_metadata.py

@@ -0,0 +1,69 @@
+from django.db import migrations, models
+import django.utils.timezone
+from django.conf import settings
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("documents", "1035_rename_comment_note"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="Metadata",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "data",
+                    models.JSONField(
+                        blank=True,
+                        help_text="JSON metadata",
+                        verbose_name="data"
+                    ),
+                ),
+                (
+                    "created",
+                    models.DateTimeField(
+                        db_index=True,
+                        default=django.utils.timezone.now,
+                        verbose_name="created",
+                    ),
+                ),
+                (
+                    "document",
+                    models.ForeignKey(
+                        blank=True,
+                        null=True,
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="metadatas",
+                        to="documents.document",
+                        verbose_name="document",
+                    ),
+                ),
+                (
+                    "user",
+                    models.ForeignKey(
+                        blank=True,
+                        null=True,
+                        on_delete=django.db.models.deletion.SET_NULL,
+                        related_name="metadatas",
+                        to=settings.AUTH_USER_MODEL,
+                        verbose_name="user",
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "metadata",
+                "verbose_name_plural": "metadatas",
+                "ordering": ("created",),
+            },
+        ),
+    ]