Fix: Increase Snapshot URL max_length from 200 to 1600 characters

- Updated Snapshot.url field in archivebox/core/models.py to max_length=1600
- Created migration 0025_alter_snapshot_url_max_length.py
- Fixes issue where URLs longer than 200 characters could not be saved in Admin UI

Fixes #1688

Co-authored-by: Nick Sweeting <pirate@users.noreply.github.com>

archivebox/core/migrations/0025_alter_snapshot_url_max_length.py

@@ -0,0 +1,19 @@
+# Generated by hand on 2025-12-29
+# Increases Snapshot.url max_length from 200 to 1600 characters
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0024_assign_default_crawl'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='snapshot',
+            name='url',
+            field=models.URLField(max_length=1600, db_index=True),
+        ),
+    ]

archivebox/core/models.py

@@ -281,7 +281,7 @@ class Snapshot(ModelWithOutputDir, ModelWithConfig, ModelWithNotes, ModelWithHea
     created_at = models.DateTimeField(default=timezone.now, db_index=True)
     modified_at = models.DateTimeField(auto_now=True)
 
-    url = models.URLField(unique=False, db_index=True)  # URLs can appear in multiple crawls
+    url = models.URLField(max_length=1600, unique=False, db_index=True)  # URLs can appear in multiple crawls
     timestamp = models.CharField(max_length=32, unique=True, db_index=True, editable=False)
     bookmarked_at = models.DateTimeField(default=timezone.now, db_index=True)
     crawl: Crawl = models.ForeignKey(Crawl, on_delete=models.CASCADE, null=False, related_name='snapshot_set', db_index=True)  # type: ignore[assignment]