extensions/migrations/0031_extension_latest_version.py

@@ -3,6 +3,34 @@
 from django.db import migrations, models
 import django.db.models.deletion
 
+from constants.base import (
+    EXTENSION_STATUS_CHOICES,
+    FILE_STATUS_CHOICES,
+)
+
+
+def valid_file_statuses(self):
+    if self.status == EXTENSION_STATUS_CHOICES.APPROVED:
+        return [FILE_STATUS_CHOICES.APPROVED]
+    return [FILE_STATUS_CHOICES.AWAITING_REVIEW, FILE_STATUS_CHOICES.APPROVED]
+
+
+def populate_latest_version(apps, schema_editor):
+    Extension = apps.get_model('extensions', 'Extension')
+    for extension in Extension.objects.prefetch_related(
+            'versions',
+            'versions__file',
+            ).all():
+        versions = extension.versions.all().order_by('-date_created')
+        latest_version = None
+        for version in versions:
+            if version.file.status not in valid_file_statuses(extension):
+                continue
+            latest_version = version
+            break
+        extension.latest_version = latest_version
+        extension.save(update_fields={'latest_version'})
+
 
 class Migration(migrations.Migration):
 
@@ -16,4 +44,5 @@ class Migration(migrations.Migration):
             name='latest_version',
             field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='latest_version_of', to='extensions.version'),
         ),
+        migrations.RunPython(populate_latest_version, reverse_code=migrations.RunPython.noop),
     ]