add filename to NonstopFile model

This will be useful once all files are moved to the same directory and a
symlink farm put in use.

nonstop/management/commands/create_tracks_from_nonstop.py

@@ -66,5 +66,6 @@ class Command(BaseCommand):
                     track.sabam = False
                     break
             nonstopfile.track = track
+            nonstopfile.filename = os.path.basename(nonstopfile.filepath)
             nonstopfile.save()
             track.save()

nonstop/migrations/0005_nonstopfile_filename.py

+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+import os
+
+from django.db import migrations, models
+
+def create_filenames(apps, schema_editor):
+    NonstopFile = apps.get_model('nonstop', 'NonstopFile')
+    for nonstop_file in NonstopFile.objects.filter(filename__isnull=True):
+        nonstop_file.filename = os.path.basename(nonstop_file.filepath)
+        nonstop_file.save()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('nonstop', '0004_auto_20170418_1525'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='nonstopfile',
+            name='filename',
+            field=models.CharField(max_length=255, null=True, verbose_name='Filename', unique=True),
+        ),
+        migrations.RunPython(create_filenames, lambda x, y: None),
+    ]

nonstop/models.py

@@ -50,6 +50,7 @@ class Track(models.Model):
 
 class NonstopFile(models.Model):
     filepath = models.CharField(_('Filepath'), max_length=255)
+    filename = models.CharField(_('Filename'), max_length=255, null=True, unique=True)
     creation_timestamp = models.DateTimeField(auto_now_add=True, null=True)
     track = models.ForeignKey(Track, null=True)