Improve slow startup times. #126

providers/sigrefdata/sig_ref_data_provider.py

@@ -17,6 +17,7 @@ class SIGRefDataProvider:
         self.last_update_time = datetime.min.replace(tzinfo=pytz.UTC)
         self.status = "Not Started" if self.enabled else "Disabled"
         self.reference_count = 0
+        self._stop = False
 
 
     def start(self):
@@ -26,14 +27,22 @@ class SIGRefDataProvider:
 
 
     def stop(self):
-        """Stop any threads and prepare for application shutdown"""
+        """Stop any threads and prepare for application shutdown. Subclasses should implement this method and call
+        super()."""
 
-        raise NotImplementedError("Subclasses must implement this method")
+        self._stop = True
 
     def _add_data(self, new_data):
         """Add all the provided reference data objects to the data store."""
 
         for d in new_data:
             DATA_STORE.sigrefs[self.sig_name + ":" + d.id] = d
+
+            # For the big data sources, loading will take a few minutes. If we want to shut down the software neatly
+            # within the first few minutes of startup, we need a way to abort this expensive process of filling up the
+            # disk cache.
+            if self._stop:
+                break
+
         self.reference_count = len(new_data)
         logging.info(f"Loaded %d references for %s into the data store.", self.reference_count, self.sig_name)