core: rotate log file at every restart (#181)

README.md

@@ -18,6 +18,8 @@ If I want my printer to light itself on fire, I should be able to make my printe
 
 - [core: danger_options](https://github.com/DangerKlippers/danger-klipper/pull/67)
 
+- [core: rotate log file at every restart](https://github.com/DangerKlippers/danger-klipper/pull/181)
+
 - [fan: normalising Fan PWM power](https://github.com/DangerKlippers/danger-klipper/pull/44) ([klipper#6307](https://github.com/Klipper3d/klipper/pull/6307))
 
 - [fan: reverse FAN](https://github.com/DangerKlippers/danger-klipper/pull/51) ([klipper#4983](https://github.com/Klipper3d/klipper/pull/4983))

klippy/klippy.py

@@ -436,6 +436,11 @@ def main():
         dest="logfile",
         help="write log to file instead of stderr",
     )
+    opts.add_option(
+        "--rotate-log-at-restart",
+        action="store_true",
+        help="rotate the log file at every restart",
+    )
     opts.add_option(
         "-v", action="store_true", dest="verbose", help="enable debug messages"
     )
@@ -485,7 +490,13 @@ def main():
     bglogger = None
     if options.logfile:
         start_args["log_file"] = options.logfile
-        bglogger = queuelogger.setup_bg_logging(options.logfile, debuglevel)
+        bglogger = queuelogger.setup_bg_logging(
+            filename=options.logfile,
+            debuglevel=debuglevel,
+            rotate_log_at_restart=options.rotate_log_at_restart,
+        )
+        if options.rotate_log_at_restart:
+            bglogger.doRollover()
     else:
         logging.getLogger().setLevel(debuglevel)
     logging.info("=======================")
@@ -532,6 +543,8 @@ def main():
         main_reactor = printer = None
         logging.info("Restarting printer")
         start_args["start_reason"] = res
+        if options.rotate_log_at_restart and bglogger is not None:
+            bglogger.doRollover()
 
     if bglogger is not None:
         bglogger.stop()

klippy/queuelogger.py

@@ -5,6 +5,7 @@
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import logging, logging.handlers, threading, queue, time
 
+
 # Class to forward all messages through a queue to a background thread
 class QueueHandler(logging.Handler):
     def __init__(self, queue):
@@ -24,10 +25,15 @@ def emit(self, record):
 
 # Class to poll a queue in a background thread and log each message
 class QueueListener(logging.handlers.TimedRotatingFileHandler):
-    def __init__(self, filename):
-        logging.handlers.TimedRotatingFileHandler.__init__(
-            self, filename, when="midnight", backupCount=5
-        )
+    def __init__(self, filename, rotate_log_at_restart):
+        if rotate_log_at_restart:
+            logging.handlers.TimedRotatingFileHandler.__init__(
+                self, filename, when="S", interval=60 * 60 * 24, backupCount=5
+            )
+        else:
+            logging.handlers.TimedRotatingFileHandler.__init__(
+                self, filename, when="midnight", backupCount=5
+            )
         self.bg_queue = queue.Queue()
         self.bg_thread = threading.Thread(target=self._bg_thread)
         self.bg_thread.start()
@@ -72,9 +78,11 @@ def doRollover(self):
 MainQueueHandler = None
 
 
-def setup_bg_logging(filename, debuglevel):
+def setup_bg_logging(filename, debuglevel, rotate_log_at_restart):
     global MainQueueHandler
-    ql = QueueListener(filename)
+    ql = QueueListener(
+        filename=filename, rotate_log_at_restart=rotate_log_at_restart
+    )
     MainQueueHandler = QueueHandler(ql.bg_queue)
     root = logging.getLogger()
     root.addHandler(MainQueueHandler)