Give label styles their own model.

storage/admin.py

@@ -4,7 +4,7 @@ from django.contrib import admin
 from django_select2.forms import ModelSelect2Widget, Select2MultipleWidget
 
 
-from .models import Item, ItemImage, Category, Label
+from .models import Item, ItemImage, Category, Label, LabelStyle
 from .widgets import ItemSelectWidget, PropsSelectWidget
 
 
@@ -83,6 +83,7 @@ class ItemAdmin(StaffModelAdmin):
 
 admin.site.register(Item, ItemAdmin)
 admin.site.register(Category, StaffModelAdmin)
+admin.site.register(LabelStyle, StaffModelAdmin)
 
 from django.contrib.auth.models import User
 from django.contrib.auth.models import Group

storage/migrations/0007_label_styles.py

@@ -0,0 +1,70 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+import uuid
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+def create_default_label(apps, schema_editor):
+    LabelStyle = apps.get_model("storage", "LabelStyle")
+    LabelStyle.objects.create(
+        old_name="basic_99012_v1",
+        description="Basic Dymo 89x36mm label",
+        length=89,
+        width=36,
+    )
+
+
+def fix_label_styles(apps, schema_editor):
+    Label = apps.get_model("storage", "Label")
+    LabelStyle = apps.get_model("storage", "LabelStyle")
+    style = LabelStyle.objects.get(old_name="basic_99012_v1")
+    for label in Label.objects.all():
+        if label.style == "basic_99012_v1":
+            label.style = style.uuid
+            label.save()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("storage", "0006_category_icon_id"),
+    ]
+
+    operations = [
+        # First set length to 36, to accomodate for UUIDs
+        migrations.AlterField(
+            model_name="label",
+            name="style",
+            field=models.CharField(max_length=36),
+        ),
+        migrations.CreateModel(
+            name="LabelStyle",
+            fields=[
+                (
+                    "uuid",
+                    models.UUIDField(
+                        primary_key=True,
+                        default=uuid.uuid4,
+                        editable=False,
+                        serialize=False,
+                    ),
+                ),
+                ("old_name", models.CharField(max_length=64)),
+                ("description", models.CharField(max_length=64)),
+                ("length", models.PositiveIntegerField()),
+                ("width", models.PositiveIntegerField()),
+            ],
+        ),
+        # Create default label, equivalent to old basic_99012_v1 style
+        migrations.RunPython(create_default_label),
+        migrations.RunPython(fix_label_styles),
+        migrations.AlterField(
+            model_name="label",
+            name="style",
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.CASCADE, to="storage.LabelStyle"
+            ),
+        ),
+    ]

storage/models.py

@@ -97,12 +97,21 @@ class ItemImage(models.Model):
         return '{}'.format(self.image.name)
 
 
+class LabelStyle(models.Model):
+    uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
+    old_name = models.CharField(max_length=64, editable=False, blank=True)
+    description = models.CharField(max_length=64)
+    length = models.PositiveIntegerField()
+    width = models.PositiveIntegerField()
+
+    def __str__(self):
+        return self.description
+
+
 class Label(models.Model):
     id = models.CharField(max_length=64, primary_key=True)
     item = models.ForeignKey(Item, related_name='labels')
-    style = models.CharField(max_length=32, choices=(
-        ('basic_99012_v1', 'Basic Dymo 89x36mm label'),
-        ), default='basic_99012_v1')
+    style = models.ForeignKey(LabelStyle)
     created = models.DateTimeField(auto_now_add=True, blank=True)
 
     def __str__(self):

storage/serializers.py

@@ -1,4 +1,4 @@
-from storage.models import Item, Label
+from storage.models import Item, Label, LabelStyle
 from rest_framework import serializers
 from rest_framework_hstore.serializers import HStoreSerializer
 
@@ -8,9 +8,17 @@ class ItemSerializer(HStoreSerializer):
         model = Item
         fields = ('uuid', 'name', 'description', 'props', 'state', 'parent')
 
+
+class LabelStyleSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = LabelStyle
+        fields = ('uuid', 'description', 'length', 'width')
+
+
 class LabelSerializer(serializers.ModelSerializer):
     item = ItemSerializer(required=False)
     item_id = serializers.PrimaryKeyRelatedField(queryset=Item.objects, source='item')
+    style = LabelStyleSerializer(required=True)
     class Meta:
         model = Label
         fields = ('id', 'item', 'item_id', 'style')