Prevent duplication of unique parts

InvenTree/part/models.py

@@ -149,11 +149,9 @@ class PartParameterManager(models.Manager):
         part_id = kwargs['part']
         template_id = kwargs['template']
 
-        try:
+        params = self.filter(part=part_id, template=template_id)
-            params = self.filter(part=part_id, template=template_id)
+        if len(params) > 0:
             return params[0]
-        except:
-            pass
 
         return super(PartParameterManager, self).create(*args, **kwargs)
 

InvenTree/project/models.py

@@ -50,11 +50,9 @@ class ProjectPartManager(models.Manager):
         project_id = kwargs['project']
         part_id = kwargs['part']
 
-        try:
+        project_parts = self.filter(project=project_id, part=part_id)
-            project_parts = self.filter(project=project_id, part=part_id)
+        if len(project_parts) > 0:
             return project_parts[0]
-        except:
-            pass
 
         return super(ProjectPartManager, self).create(*args, **kwargs)
 

InvenTree/track/models.py

@@ -1,4 +1,5 @@
 from __future__ import unicode_literals
+from django.core.exceptions import ValidationError
 from django.utils.translation import ugettext as _
 from django.db import models
 from django.contrib.auth.models import User
@@ -7,12 +8,37 @@ from supplier.models import Customer
 from part.models import Part, PartRevision
 
 
+class UniquePartManager(models.Manager):
+    """ Ensures UniqueParts are correctly handled
+    """
+
+    def create(self, *args, **kwargs):
+
+        part_id = kwargs['part']
+        sn = kwargs.get('serial', None)
+
+        if not sn:
+            raise ValidationError(_("Serial number must be supplied"))
+
+        if not isinstance(sn, int):
+            raise ValidationError(_("Serial number must be integer"))
+
+        # Does a part already exists with this serial number?
+        parts = self.filter(part=part_id, serial=sn)
+        if len(parts) > 0:
+            raise ValidationError(_("Matching part and serial number found!"))
+
+        return super(UniquePartManager, self).create(*args, **kwargs)
+
+
 class UniquePart(models.Model):
     """ A unique instance of a Part object.
     Used for tracking parts based on serial numbers,
     and tracking all events in the life of a part
     """
 
+    objects = UniquePartManager()
+
     part = models.ForeignKey(Part, on_delete=models.CASCADE)
 
     revision = models.ForeignKey(PartRevision,
@@ -50,6 +76,17 @@ class UniquePart(models.Model):
     def __str__(self):
         return self.part.name
 
+    def save(self, *args, **kwargs):
+
+        # Disallow saving a serial number that already exists
+        matches = UniquePart.objects.filter(serial=self.serial, part=self.part)
+        matches = matches.filter(~models.Q(id = self.id))
+
+        if len(matches) > 0:
+            raise ValidationError(_("Matching serial number already exists"))
+
+        super(UniquePart, self).save(*args, **kwargs)
+
 
 class PartTrackingInfo(models.Model):
     """ Single data-point in the life of a UniquePart