More elegant error handling

ref-test/app/tools/forms.py

@@ -1,6 +1,7 @@
 
 from ..extensions import db
 
+from flask import jsonify
 from wtforms.validators import ValidationError
 
 import json
@@ -53,4 +54,8 @@ def get_dataset_choices():
         label = f'{label} (Default)' if dataset.default else label
         choice = (dataset.id, label)
         dataset_choices.append(choice)
-    return dataset_choices
+    return dataset_choices
+
+def send_errors_to_client(form):
+    errors = [*form.errors]
+    return jsonify({ 'error': errors}), 400