Barcode Refactor (#3640)

* define a simple model mixin class for barcode

* Adds generic function for assigning a barcode to a model instance

* StockItem model now implements the BarcodeMixin class

* Implement simple unit tests for new code

* Fix unit tests

* Data migration for uid field

* Remove references to old 'uid' field

* Migration for removing old uid field from StockItem model

* Bump API version

* Change lookup_barcode to be a classmethod

* Change barcode_model_type to be a class method

* Cleanup for generic barcode scan and assign API:

- Raise ValidationError as appropriate
- Improved unit testing
- Groundwork for future generic implementation

* Further unit tests for barcode scanning

* Adjust error messages for compatibility

* Unit test fix

* Fix hash_barcode function

- Add unit tests to ensure it produces the same results as before the refactor

* Add BarcodeMixin to Part model

* Remove old format_barcode function from Part model

* Further fixes for unit tests

* Add support for assigning arbitrary barcode to Part instance

- Simplify barcode API
- Add more unit tests

* More unit test fixes

* Update unit test

* Adds generic endpoint for unassigning barcode data

* Update web dialog for unlinking a barcode

* Template cleanup

* Add Barcode mixin to StockLocation class

* Add some simple unit tests for new model mixin

* Support assigning / unassigning barcodes for StockLocation

* remove failing outdated test

* Update template to integrate new barcode support for StockLocation

* Add BarcodeMixin to SupplierPart model

* Adds QR code view for SupplierPart

* Major simplification of barcode API endpoints

- Separate existing barcode plugin into two separate classes
- Simplify and consolidate the response from barcode scanning
- Update unit testing

* Yet more unit test fixes

* Yet yet more unit test fixes

InvenTree/label/models.py

@@ -249,7 +249,8 @@ class StockItemLabel(LabelTemplate):
             'revision': stock_item.part.revision,
             'quantity': normalize(stock_item.quantity),
             'serial': stock_item.serial,
-            'uid': stock_item.uid,
+            'barcode_data': stock_item.barcode_data,
+            'barcode_hash': stock_item.barcode_hash,
             'qr_data': stock_item.format_barcode(brief=True),
             'qr_url': stock_item.format_barcode(url=True, request=request),
             'tests': stock_item.testResultMap(),