QR code improvements

- Display QR codes as links to served images
- The qr_code plugin caches these images in the background
- Make a qr_code template to push out as a modal form
- Create a QRCodeView to simplify display of QR codes
- Add option to launchModalForm() to disable the 'submit' button

Refactored QR code display for

- StockLocation
- StockItem
- Part

InvenTree/part/views.py

@@ -27,6 +27,7 @@ from .forms import BomExportForm
 from .forms import EditSupplierPartForm
 
 from InvenTree.views import AjaxView, AjaxCreateView, AjaxUpdateView, AjaxDeleteView
+from InvenTree.views import QRCodeView
 
 from InvenTree.helpers import DownloadFile, str2bool
 
@@ -234,6 +235,21 @@ class PartDetail(DetailView):
         return context
 
 
+class PartQRCode(QRCodeView):
+    """ View for displaying a QR code for a Part object """
+
+    ajax_form_title = "Part QR Code"
+
+    def get_qr_data(self):
+        """ Generate QR code data for the Part """
+
+        try:
+            part = Part.objects.get(id=self.pk)
+            return part.format_barcode()
+        except Part.DoesNotExist:
+            return None
+
+
 class PartImage(AjaxUpdateView):
     """ View for uploading Part image """