Move "getAvailableStockItems" to the build model

InvenTree/build/migrations/0026_auto_20201023_1228.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.0.7 on 2020-10-23 12:28
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0052_stockitem_is_building'),
+        ('build', '0025_auto_20201020_1248'),
+    ]
+
+    operations = [
+        migrations.AlterUniqueTogether(
+            name='builditem',
+            unique_together={('build', 'stock_item', 'install_into')},
+        ),
+    ]

InvenTree/build/models.py

@@ -551,6 +551,39 @@ class Build(MPTTModel):
 
         return parts
 
+    def getAvailableStockItems(self, part=None, output=None):
+        """
+        Return available stock items for the build.
+        """
+
+        items = StockModels.StockItem.objects.filter(StockModels.StockItem.IN_STOCK_FILTER)
+
+        if part:
+            # Filter items which match the given Part
+            items = items.filter(part=part)
+
+            if output:
+                # Exclude items which are already allocated to the particular build output
+
+                to_exclude = BuildItem.objects.filter(
+                    build=self,
+                    stock_item__part=part,
+                    install_into=output
+                )
+
+                items = items.exclude(
+                    id__in=[item.stock_item.id for item in to_exclude.all()]
+                )
+
+        # Limit query to stock items which are "downstream" of the source location
+        if self.take_from is not None:
+            items = items.filter(
+                location__in=[loc for loc in self.take_from.getUniqueChildren()]
+            )
+
+        return items
+
+
     @property
     def can_build(self):
         """ Return true if there are enough parts to supply build """
@@ -597,7 +630,7 @@ class BuildItem(models.Model):
 
     class Meta:
         unique_together = [
-            ('build', 'stock_item'),
+            ('build', 'stock_item', 'install_into'),
         ]
 
     def clean(self):
@@ -613,24 +646,34 @@ class BuildItem(models.Model):
         errors = {}
 
         try:
+            # Allocated part must be in the BOM for the master part
             if self.stock_item.part not in self.build.part.getRequiredParts(recursive=False):
                 errors['stock_item'] = [_("Selected stock item not found in BOM for part '{p}'".format(p=self.build.part.full_name))]
             
+            # Allocated quantity cannot exceed available stock quantity
             if self.quantity > self.stock_item.quantity:
                 errors['quantity'] = [_("Allocated quantity ({n}) must not exceed available quantity ({q})".format(
                     n=normalize(self.quantity),
                     q=normalize(self.stock_item.quantity)
                 ))]
 
+            # Allocated quantity cannot cause the stock item to be over-allocated
             if self.stock_item.quantity - self.stock_item.allocation_count() + self.quantity < self.quantity:
                 errors['quantity'] = _('StockItem is over-allocated')
 
+            # Allocated quantity must be positive
             if self.quantity <= 0:
                 errors['quantity'] = _('Allocation quantity must be greater than zero')
 
+            # Quantity must be 1 for serialized stock
             if self.stock_item.serial and not self.quantity == 1:
                 errors['quantity'] = _('Quantity must be 1 for serialized stock')
 
+            # Part reference must match between output stock item and built part
+            if self.install_into is not None:
+                if not self.install_into.part == self.build.part:
+                    errors['install_into'] = _('Part reference differs between build and build output')
+
         except (StockModels.StockItem.DoesNotExist, PartModels.Part.DoesNotExist):
             pass
 

InvenTree/build/views.py

@@ -535,6 +535,10 @@ class BuildItemCreate(AjaxCreateView):
 
         form = super(AjaxCreateView, self).get_form()
 
+        self.build = None
+        self.part = None
+        self.output = None
+
         # If the Build object is specified, hide the input field.
         # We do not want the users to be able to move a BuildItem to a different build
         build_id = form['build'].value()
@@ -546,14 +550,13 @@ class BuildItemCreate(AjaxCreateView):
             """
             form.fields['build'].widget = HiddenInput()
             form.fields['install_into'].queryset = StockItem.objects.filter(build=build_id, is_building=True)
+            self.build = Build.objects.get(pk=build_id)
         else:
             """
             Build has *not* been selected
             """
             pass
 
-        self.output = None
-
         # If the output stock item is specified, hide the input field
         output_id = form['install_into'].value()
 
@@ -568,47 +571,18 @@ class BuildItemCreate(AjaxCreateView):
         # If the sub_part is supplied, limit to matching stock items
         part_id = self.get_param('part')
 
-        # We need to precisely control which StockItem objects the user can choose to allocate
-        stock_filter = form.fields['stock_item'].queryset
-
-        # Restrict to only items which are "in stock"
-        stock_filter = stock_filter.filter(StockItem.IN_STOCK_FILTER)
-
         if part_id:
             try:
                 self.part = Part.objects.get(pk=part_id)
        
-                # Only allow StockItem objects which match the current part
-                stock_filter = stock_filter.filter(part=part_id)
-
-                if build_id is not None:
-                    try:
-                        build = Build.objects.get(id=build_id)
-                        
-                        if build.take_from is not None:
-                            # Limit query to stock items that are downstream of the 'take_from' location
-                            stock_filter = stock_filter.filter(location__in=[loc for loc in build.take_from.getUniqueChildren()])
-                            
-                    except Build.DoesNotExist:
+            except (ValueError, Part.DoesNotExist):
                 pass
 
-                    # Exclude StockItem objects which are already allocated to this build and part
-                    to_exclude = BuildItem.objects.filter(build=build_id, stock_item__part=part_id)
-                    if self.output:
-                        to_exclude = to_exclude.filter(install_into=self.output)
+        if self.build and self.part:
+            available_items = self.build.getAvailableStockItems(part=self.part, output=self.output)
+            form.fields['stock_item'].queryset = available_items
 
-                    stock_filter = stock_filter.exclude(id__in=[item.stock_item.id for item in to_exclude.all()])
-
-            except Part.DoesNotExist:
-                self.part = None
-                pass
-
-        else:
-            self.part = None
-
-        form.fields['stock_item'].queryset = stock_filter
-
-        self.available_stock = stock_filter.all()
+        self.available_stock = form.fields['stock_item'].queryset.all()
 
         # If there is only a single stockitem available, select it!
         if len(self.available_stock) == 1:

InvenTree/stock/models.py

@@ -139,6 +139,7 @@ class StockItem(MPTTModel):
 
     # A Query filter which will be re-used in multiple places to determine if a StockItem is actually "in stock"
     IN_STOCK_FILTER = Q(
+        quantity__gt=0,
         sales_order=None,
         build_order=None,
         belongs_to=None,