Update definition for StockItemAllocation model

- Limit foreignkey choices
- Error checking
- Check if a StockItem is over-allocated
- Fix API serialization and filtering

InvenTree/order/admin.py

@@ -10,7 +10,7 @@ from import_export.fields import Field
 
 from .models import PurchaseOrder, PurchaseOrderLineItem
 from .models import SalesOrder, SalesOrderLineItem
-
+from .models import SalesOrderAllocation
 
 class PurchaseOrderAdmin(ImportExportModelAdmin):
 
@@ -86,8 +86,19 @@ class SalesOrderLineItemAdmin(ImportExportModelAdmin):
     )
 
 
+class SalesOrderAllocationAdmin(ImportExportModelAdmin):
+
+    list_display = (
+        'line',
+        'item',
+        'quantity'
+    )
+
+
 admin.site.register(PurchaseOrder, PurchaseOrderAdmin)
 admin.site.register(PurchaseOrderLineItem, PurchaseOrderLineItemAdmin)
 
 admin.site.register(SalesOrder, SalesOrderAdmin)
 admin.site.register(SalesOrderLineItem, SalesOrderLineItemAdmin)
+
+admin.site.register(SalesOrderAllocation, SalesOrderAllocationAdmin)

InvenTree/order/migrations/0025_auto_20200422_0222.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.0.5 on 2020-04-22 02:22
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0031_auto_20200422_0209'),
+        ('order', '0024_salesorderallocation'),
+    ]
+
+    operations = [
+        migrations.AlterUniqueTogether(
+            name='salesorderallocation',
+            unique_together={('line', 'item')},
+        ),
+    ]

InvenTree/order/migrations/0026_auto_20200422_0224.py

@@ -0,0 +1,20 @@
+# Generated by Django 3.0.5 on 2020-04-22 02:24
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0031_auto_20200422_0209'),
+        ('order', '0025_auto_20200422_0222'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='salesorderallocation',
+            name='item',
+            field=models.OneToOneField(limit_choices_to={'part__salable': True}, on_delete=django.db.models.deletion.CASCADE, related_name='sales_order_allocation', to='stock.StockItem'),
+        ),
+    ]

InvenTree/order/migrations/0027_auto_20200422_0236.py

@@ -0,0 +1,20 @@
+# Generated by Django 3.0.5 on 2020-04-22 02:36
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0031_auto_20200422_0209'),
+        ('order', '0026_auto_20200422_0224'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='salesorderallocation',
+            name='item',
+            field=models.ForeignKey(limit_choices_to={'part__salable': True}, on_delete=django.db.models.deletion.CASCADE, related_name='sales_order_allocations', to='stock.StockItem'),
+        ),
+    ]

InvenTree/order/models.py

@@ -398,8 +398,55 @@ class SalesOrderAllocation(models.Model):
 
     """
 
+    class Meta:
+        unique_together = [
+            # Cannot allocate any given StockItem to the same line more than once
+            ('line', 'item'),
+        ]
+
+    def clean(self):
+        """
+        Validate the SalesOrderAllocation object:
+
+        - Cannot allocate stock to a line item without a part reference
+        - The referenced part must match the part associated with the line item
+        - Allocated quantity cannot exceed the quantity of the stock item
+        - Allocation quantity must be "1" if the StockItem is serialized
+        - Allocation quantity cannot be zero
+        """
+
+        super().clean()
+
+        errors = {}
+
+        try:
+            if not self.line.part == self.item.part:
+                errors['item'] = _('Cannot allocate stock item to a line with a different part')
+        except Part.DoesNotExist:
+            errors['line'] = _('Cannot allocate stock to a line without a part')
+
+        if self.quantity > self.item.quantity:
+            errors['quantity'] = _('Allocation quantity cannot exceed stock quantity')
+
+        if self.item.quantity - self.item.allocation_count() < self.quantity:
+            errors['quantity'] = _('StockItem is over-allocated')
+
+        if self.quantity <= 0:
+            errors['quantity'] = _('Allocation quantity must be greater than zero')
+
+        if self.item.serial and not self.quantity == 1:
+            errors['quantity'] = _('Quantity must be 1 for serialized stock item')
+
+        if len(errors) > 0:
+            raise ValidationError(errors)
+
     line = models.ForeignKey(SalesOrderLineItem, on_delete=models.CASCADE, related_name='allocations')
 
-    item = models.OneToOneField('stock.StockItem', on_delete=models.CASCADE, related_name='sales_order_allocation')
+    item = models.ForeignKey(
+        'stock.StockItem',
+        on_delete=models.CASCADE,
+        related_name='sales_order_allocations',
+        limit_choices_to={'part__salable': True},
+    )
 
     quantity = RoundingDecimalField(max_digits=15, decimal_places=5, validators=[MinValueValidator(0)], default=1)