Use slugs to filter

ram/metadata/migrations/0011_company_slug_and_more.py

@@ -0,0 +1,93 @@
+# Generated by Django 4.1.5 on 2023-01-09 11:22
+
+from django.db import migrations, models
+
+
+from ram.utils import slugify
+
+
+def create_slug(apps, schema_editor):
+    fields = ["Company", "Manufacturer", "RollingStockType", "Scale"]
+
+    for m in fields:
+        model = apps.get_model("metadata", m)
+
+        for row in model.objects.all():
+            if hasattr(row, "type"):
+                row.slug = slugify("{} {}".format(row.type, row.category))
+            elif hasattr(row, "scale"):
+                row.slug = slugify(row.scale)
+            else:
+                row.slug = slugify(row.name)
+
+            row.save(update_fields=["slug"])
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("metadata", "0010_alter_manufacturer_category"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="company",
+            name="slug",
+            field=models.CharField(
+                editable=False, max_length=64, blank=True
+            ),
+        ),
+        migrations.AddField(
+            model_name="manufacturer",
+            name="slug",
+            field=models.CharField(
+                editable=False, max_length=128, blank=True
+            ),
+        ),
+        migrations.AddField(
+            model_name="rollingstocktype",
+            name="slug",
+            field=models.CharField(
+                editable=False, max_length=128, blank=True
+            ),
+        ),
+        migrations.AddField(
+            model_name="scale",
+            name="slug",
+            field=models.CharField(
+                editable=False, max_length=32, blank=True
+            ),
+        ),
+        migrations.RunPython(
+            create_slug,
+            reverse_code=migrations.RunPython.noop
+        ),
+        migrations.AlterField(
+            model_name="company",
+            name="slug",
+            field=models.CharField(
+                editable=False, max_length=64, unique=True
+            ),
+        ),
+        migrations.AlterField(
+            model_name="manufacturer",
+            name="slug",
+            field=models.CharField(
+                editable=False, max_length=128, unique=True
+            ),
+        ),
+        migrations.AlterField(
+            model_name="rollingstocktype",
+            name="slug",
+            field=models.CharField(
+                editable=False, max_length=128, unique=True
+            ),
+        ),
+        migrations.AlterField(
+            model_name="scale",
+            name="slug",
+            field=models.CharField(
+                editable=False, max_length=32, unique=True
+            ),
+        ),
+    ]