863 followup

kolibri_explore_plugin/collectionviews.py

@@ -240,7 +240,13 @@ def _set_empty_state(self):
         self._enqueuing_timestamp = None
         self._enqueued_timestamp = None
 
-    def from_manifest(self, manifest, user):
+    def is_state_unset(self):
+        return (
+            self._stage == DownloadStage.NOT_STARTED
+            and self._content_manifest is None
+        )
+
+    def start(self, manifest, user):
         """Start downloading a collection manifest."""
         if self._stage != DownloadStage.NOT_STARTED:
             raise DownloadError("A download has already started. Can't start")
@@ -265,6 +271,12 @@ def from_state(self, state):
         self._tasks_completed = state["tasks_completed"]
         self._tasks_previously_completed = state["tasks_previously_completed"]
 
+        logger.info(
+            f"Download state loaded for grade={grade} name={name}, "
+            + f"stage={stage_name}"
+        )
+        logger.debug(f"Loaded download state: {state}")
+
     def cancel(self):
         if self._current_job_id is not None:
             job_storage.cancel(self._current_job_id)
@@ -646,7 +658,7 @@ def start_download(request):
 
     # Init the download manager and start downloading
     try:
-        _collection_download_manager.from_manifest(manifest, request.user)
+        _collection_download_manager.start(manifest, request.user)
         logger.info(f"Download started for grade={grade} name={name}")
     except DownloadError as err:
         raise APIException(err)
@@ -733,5 +745,13 @@ def cancel_download(request):
 @api_view(["GET"])
 def get_download_status(request):
     """Return the download status."""
+
+    saved_state = request.session.get("COLLECTIONS_STATE")
+    if (
+        _collection_download_manager.is_state_unset()
+        and saved_state is not None
+    ):
+        _collection_download_manager.from_state(saved_state)
+
     status = _collection_download_manager.get_status()
     return Response({"status": status})