Use int sort for road numbers

ram/roster/migrations/0009_alter_rollingstock_options_and_more.py

@@ -0,0 +1,41 @@
+# Generated by Django 4.0.6 on 2022-07-16 15:38
+
+import re
+from django.db import migrations, models
+
+
+def gen_road_number_cleaned(apps, schema_editor):
+    RollingStock = apps.get_model('roster', 'RollingStock')
+    for row in RollingStock.objects.all():
+        try:
+            row.road_number_int = int(re.findall(r"\d+", row.road_number)[0])
+            row.save(update_fields=['road_number_int'])
+        except IndexError:
+            pass
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('roster', '0008_rollingstock_road_number_cleaned'),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name='rollingstock',
+            options={'ordering': ['rolling_class', 'road_number_int'], 'verbose_name_plural': 'Rolling stock'},
+        ),
+        migrations.RemoveField(
+            model_name='rollingstock',
+            name='road_number_cleaned',
+        ),
+        migrations.AddField(
+            model_name='rollingstock',
+            name='road_number_int',
+            field=models.PositiveSmallIntegerField(default=0),
+        ),
+        migrations.RunPython(
+            gen_road_number_cleaned,
+            reverse_code=migrations.RunPython.noop
+        ),
+    ]

ram/roster/models.py

@@ -1,4 +1,5 @@
 import os
+import re
 from uuid import uuid4
 from django.db import models
 from django.urls import reverse
@@ -75,7 +76,7 @@ class RollingStock(models.Model):
         verbose_name="Class",
     )
     road_number = models.CharField(max_length=128, unique=False)
-    road_number_cleaned = models.CharField(max_length=128, unique=False)
+    road_number_int = models.PositiveSmallIntegerField(default=0, unique=False)
     manufacturer = models.ForeignKey(
         Manufacturer,
         on_delete=models.CASCADE,
@@ -100,7 +101,7 @@ class RollingStock(models.Model):
     updated_time = models.DateTimeField(auto_now=True)
 
     class Meta:
-        ordering = ["rolling_class", "road_number_cleaned"]
+        ordering = ["rolling_class", "road_number_int"]
         verbose_name_plural = "Rolling stock"
 
     def __str__(self):
@@ -118,7 +119,11 @@ class RollingStock(models.Model):
 
 @receiver(models.signals.pre_save, sender=RollingStock)
 def pre_save_running_number(sender, instance, *args, **kwargs):
-    instance.road_number_cleaned = instance.road_number.lstrip("#").lstrip("0")
+    try:
+        instance.road_number_int = int(
+            re.findall(r"\d+", instance.road_number)[0])
+    except IndexError:
+        pass
 
 
 class RollingStockDocument(models.Model):