core: rehashable file loggers with log rotation support

Closes #176. Closes #315.

coremods/control.py

@@ -5,7 +5,7 @@ import signal
 import os
 
 from pylinkirc import world, utils, conf, classes
-from pylinkirc.log import log
+from pylinkirc.log import log, makeFileLogger, stopFileLoggers
 
 def remove_network(ircobj):
     """Removes a network object from the pool."""
@@ -47,6 +47,14 @@ def _rehash():
     new_conf = conf.loadConf(fname, errors_fatal=False)
     new_conf = conf.validateConf(new_conf)
     conf.conf = new_conf
+
+    # Reset any file logger options.
+    stopFileLoggers()
+    files = new_conf['logging'].get('files')
+    if files:
+        for filename, config in files.items():
+            makeFileLogger(filename, config.get('loglevel'))
+
     for network, ircobj in world.networkobjects.copy().items():
         # Server was removed from the config file, disconnect them.
         log.debug('rehash: checking if %r is in new conf still.', network)

log.py

@@ -7,12 +7,16 @@ access the global logger object by importing "log" from this module
 """
 
 import logging
+import logging.handlers
 import sys
 import os
 
 from . import world
 from .conf import conf, confname
 
+# Stores a list of active file loggers.
+fileloggers = []
+
 stdout_level = conf['logging'].get('stdout') or 'INFO'
 
 logdir = os.path.join(os.getcwd(), 'log')
@@ -43,7 +47,8 @@ def makeFileLogger(filename, level=None):
     # PyLink instances from overwriting each others' log files.
     target = os.path.join(logdir, '%s-%s.log' % (confname, filename))
 
-    filelogger = logging.FileHandler(target, mode='w')
+    # TODO: configurable values here
+    filelogger = logging.handlers.RotatingFileHandler(target, maxBytes=52428800, backupCount=5)
     filelogger.setFormatter(logformatter)
 
     # If no log level is specified, use the same one as STDOUT.
@@ -51,9 +56,21 @@ def makeFileLogger(filename, level=None):
     filelogger.setLevel(level)
 
     log.addHandler(filelogger)
+    global fileloggers
+    fileloggers.append(filelogger)
 
     return filelogger
 
+def stopFileLoggers():
+    """
+    De-initializes all file loggers.
+    """
+    global fileloggers
+    for handler in fileloggers.copy():
+        handler.close()
+        log.removeHandler(handler)
+        fileloggers.remove(handler)
+
 # Set up file logging now, creating a file logger for each block.
 files = conf['logging'].get('files')
 if files: