fix: load JS synchronously in fragment to prevent race conditions

Previously, when loading JS for virtualdom and drag_and_drop (which depends on
virtualdom) from cache, there was a risk that drag_and_drop could load before
virtualdom. This would cause virtualdom to be undefined, resulting in the
XBlock failing to load.

With these changes, the JavaScript code is now inlined in the HTML fragment.
This guarantees the correct loading order and prevents such race conditions.

Author: DanielVZ96

Changelog.md

@@ -4,6 +4,11 @@ Drag and Drop XBlock changelog
 Unreleased
 ---------------------------
 
+Version 5.0.3 (2025-06-26)
+---------------------------
+
+* Load JS synchronously in the fragment to prevent race conditions.
+
 Version 5.0.2 (2025-04-07)
 ---------------------------
 

drag_and_drop_v2/__init__.py

@@ -1,4 +1,4 @@
 """ Drag and Drop v2 XBlock """
 from .drag_and_drop_v2 import DragAndDropBlock
 
-__version__ = "5.0.2"
+__version__ = "5.0.3"

drag_and_drop_v2/drag_and_drop_v2.py

@@ -348,7 +348,7 @@ def student_view(self, context):
         for css_url in css_urls:
             fragment.add_css_url(self.runtime.local_resource_url(self, css_url))
         for js_url in js_urls:
-            fragment.add_javascript_url(self.runtime.local_resource_url(self, js_url))
+            fragment.add_javascript(loader.load_unicode(js_url))
 
         statici18n_js_url = self._get_statici18n_js_url()
         if statici18n_js_url: