Prevent incomplete/invalid surface tracker exports

pupil_src/shared_modules/surface_tracker/background_tasks.py

@@ -363,8 +363,11 @@ def _export_marker_detections(self):
         marker_cache = file_methods.Persistent_Dict(self.marker_cache_path)
         marker_cache = marker_cache["marker_cache"]
 
+        incomplete_marker_cache_detected = False
+
+        file_path = os.path.join(self.metrics_dir, "marker_detections.csv")
+
         try:
-            file_path = os.path.join(self.metrics_dir, "marker_detections.csv")
             with open(file_path, "w", encoding="utf-8", newline="") as csv_file:
                 csv_writer = csv.writer(csv_file, delimiter=",")
                 csv_writer.writerow(
@@ -382,7 +385,19 @@ def _export_marker_detections(self):
                     )
                 )
                 for idx, serialized_markers in enumerate(marker_cache):
-                    for m in map(Surface_Marker.deserialize, serialized_markers):
+                    if serialized_markers is None:
+                        # set flag to break from outer loop
+                        incomplete_marker_cache_detected = True
+
+                    if incomplete_marker_cache_detected:
+                        break  # outer loop
+
+                    for sm in serialized_markers:
+                        if sm is None:
+                            # set flag to break from outer loop
+                            incomplete_marker_cache_detected = True
+                            break  # inner loop
+                        m = Surface_Marker.deserialize(sm)
                         flat_corners = [x for c in m.verts_px for x in c[0]]
                         assert len(flat_corners) == 8  # sanity check
                         csv_writer.writerow(
@@ -393,6 +408,11 @@ def _export_marker_detections(self):
                             )
                         )
         finally:
+            if incomplete_marker_cache_detected:
+                logger.error("Marker detection not finished. No data will be exported.")
+                # Delete incomplete marker cache export file
+                os.remove(file_path)
+
             # Delete the temporary marker cache created by the offline surface tracker
             os.remove(self.marker_cache_path)
             self.marker_cache_path = None

pupil_src/shared_modules/surface_tracker/surface_tracker_offline.py

@@ -566,6 +566,17 @@ def on_notify(self, notification):
                     break
 
         elif notification["subject"] == "should_export":
+
+            if self.cache_filler is not None:
+                logger.error("Marker detection not finished. No data will be exported.")
+                return
+
+            if self.gaze_on_surf_buffer_filler is not None:
+                logger.error(
+                    "Surface gaze mapping not finished. No data will be exported."
+                )
+                return
+
             # Create new marker cache temporary file
             # Backgroud exporter is responsible of removing the temporary file when finished
             file_handle, marker_cache_path = tempfile.mkstemp()