Catch and show error, if one happens when making batch from product query

tailbone/views/products.py

@@ -40,7 +40,7 @@ from rattail.db import model, api, auth, Session as RattailSession
 from rattail.gpc import GPC
 from rattail.threads import Thread
 from rattail.exceptions import LabelPrintingError
-from rattail.util import load_object, pretty_quantity, OrderedDict
+from rattail.util import load_object, pretty_quantity, OrderedDict, simple_error
 from rattail.batch import get_batch_handler
 from rattail.time import localtime, make_utc
 
@@ -1693,14 +1693,29 @@ class ProductView(MasterView):
         user = session.query(model.User).get(user_uuid)
         assert user
         params['created_by'] = user
+        try:
             batch = handler.make_batch(session, **params)
             batch.products = products.with_session(session).all()
             handler.do_populate(batch, user, progress=progress)
 
+        except Exception as error:
+            session.rollback()
+            log.exception("failed to make '%s' batch with params: %s",
+                          handler.batch_key, params)
+            session.close()
+            if progress:
+                progress.session.load()
+                progress.session['error'] = True
+                progress.session['error_msg'] = "Failed to make '{}' batch: {}".format(
+                    handler.batch_key, simple_error(error))
+                progress.session.save()
+
+        else:
             session.commit()
             session.refresh(batch)
             session.close()
 
+            if progress:
                 progress.session.load()
                 progress.session['complete'] = True
                 progress.session['success_url'] = self.get_batch_view_url(batch)