config reload: fix feedback loop — react to modified/created/moved only, not open/close (v3.12.1 spun cpu on read-opens)

fjerkroa_bot/discord_bot.py

@@ -88,10 +88,22 @@ class ConfigFileHandler(FileSystemEventHandler):
                 return True
         return False
 
-    def on_any_event(self, event):
+    def _dispatch(self, event):
         if not event.is_directory and self._hits_config(event):
             self._on_change()
 
+    # Only write/rename events — NOT on_opened/on_closed, whose read-opens
+    # (our own load_config re-reads the file) would otherwise feed back into
+    # a reload loop (CFG-05).
+    def on_modified(self, event):
+        self._dispatch(event)
+
+    def on_created(self, event):
+        self._dispatch(event)
+
+    def on_moved(self, event):
+        self._dispatch(event)
+
 
 class FjerkroaBot(commands.Bot):
     def __init__(self, config_file: str):

specs/SPEC-008-config.md

@@ -35,9 +35,12 @@ applies directly — there are no concurrent readers yet.
 ### CFG-05 — Hot-reload is rename-safe (coverage: test)
 
 The watcher observes the config file's **directory**, not the file, and
-reacts to any event (modified, created, moved) whose source or
+reacts to a **modified, created, or moved** event whose source or
 destination path is the config file. This catches atomic saves — write
 a temp file, then rename it over the target — which replace the inode
 and fire a move/create rather than a modify; watching the file directly
-would go deaf after the first such save. Events for other files in the
+would go deaf after the first such save. Open/close events are
-directory, and directory events themselves, are ignored.
+deliberately not handled: reloading re-opens the file to read it, so
+reacting to opens would feed back into an endless reload loop. Events
+for other files in the directory, and directory events themselves, are
+ignored.

tests/test_spec_per.py

@@ -157,10 +157,15 @@ class TestConfigReloadRenameSafe(unittest.TestCase):
                 event.dest_path = dest if dest is not None else ""
                 return event
 
-            handler.on_any_event(evt(src=str(config)))  # in-place modify
+            handler.on_modified(evt(src=str(config)))  # in-place modify
-            handler.on_any_event(evt(src=str(Path(tmp) / "kroa.toml.tmp"), dest=str(config)))  # atomic rename over
+            handler.on_moved(evt(src=str(Path(tmp) / "kroa.toml.tmp"), dest=str(config)))  # atomic rename over
-            self.assertEqual(len(hits), 2)
+            handler.on_created(evt(src=str(config)))  # write-new
+            self.assertEqual(len(hits), 3)
 
-            handler.on_any_event(evt(src=str(Path(tmp) / "other.txt")))  # unrelated file
+            handler.on_modified(evt(src=str(Path(tmp) / "other.txt")))  # unrelated file
-            handler.on_any_event(evt(is_dir=True, src=str(config)))  # directory event
+            handler.on_modified(evt(is_dir=True, src=str(config)))  # directory event
-            self.assertEqual(len(hits), 2)  # neither fired
+            self.assertEqual(len(hits), 3)  # neither fired
+
+            # open/close of the config (our own load_config re-reads) must NOT be handled — else a reload loop.
+            self.assertNotIn("on_opened", vars(ConfigFileHandler))
+            self.assertNotIn("on_closed", vars(ConfigFileHandler))