Add quantity field to StockItemTracking

- Keep track of historical levels of part availability

InvenTree/stock/migrations/0005_stockitemtracking_quantity.py

@@ -0,0 +1,19 @@
+# Generated by Django 2.2 on 2019-04-12 14:09
+
+import django.core.validators
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0004_auto_20190412_2030'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='stockitemtracking',
+            name='quantity',
+            field=models.PositiveIntegerField(default=1, validators=[django.core.validators.MinValueValidator(0)]),
+        ),
+    ]

InvenTree/stock/models.py

@@ -209,6 +209,7 @@ class StockItem(models.Model):
             item=self,
             title=title,
             user=user,
+            quantity=self.quantity,
             date=datetime.now().date(),
             notes=notes,
             system=system
@@ -346,6 +347,9 @@ class StockItemTracking(models.Model):
     # Was this tracking note auto-generated by the system?
     system = models.BooleanField(default=False)
 
+    # Keep track of the StockItem quantity throughout the tracking history
+    quantity = models.PositiveIntegerField(validators=[MinValueValidator(0)], default=1)
+
     # TODO
     # image = models.ImageField(upload_to=func, max_length=255, null=True, blank=True)
 

InvenTree/stock/serializers.py

@@ -35,6 +35,7 @@ class StockTrackingSerializer(serializers.ModelSerializer):
             'date',
             'title',
             'notes',
+            'quantity',
             'user',
             'system',
         ]
@@ -43,6 +44,7 @@ class StockTrackingSerializer(serializers.ModelSerializer):
             'date',
             'user',
             'system',
+            'quantity',
         ]
 
 

InvenTree/stock/templates/stock/item.html

@@ -215,6 +215,10 @@
                     return html;
                 }
             },
+            {
+                field: 'quantity',
+                title: 'Quantity',
+            },
             {
                 sortable: true,
                 field: 'user',