import atexit
import logging
import logging.handlers
import os
import os.path
import inspect
import tuned.consts as consts
import random
import string
import threading
try:
from StringIO import StringIO
except:
from io import StringIO
__all__ = ["get"]
root_logger = None
log_handlers = {}
log_handlers_lock = threading.Lock()
class LogHandler(object):
def __init__(self, handler, stream):
self.handler = handler
self.stream = stream
def _random_string(length):
r = random.SystemRandom()
chars = string.ascii_letters + string.digits
res = ""
for i in range(length):
res += r.choice(chars)
return res
def log_capture_start(log_level):
with log_handlers_lock:
for i in range(10):
token = _random_string(16)
if token not in log_handlers:
break
else:
return None
stream = StringIO()
handler = logging.StreamHandler(stream)
handler.setLevel(log_level)
formatter = logging.Formatter(
"%(levelname)-8s %(name)s: %(message)s")
handler.setFormatter(formatter)
root_logger.addHandler(handler)
log_handler = LogHandler(handler, stream)
log_handlers[token] = log_handler
root_logger.debug("Added log handler %s." % token)
return token
def log_capture_finish(token):
with log_handlers_lock:
try:
log_handler = log_handlers[token]
except KeyError:
return None
content = log_handler.stream.getvalue()
log_handler.stream.close()
root_logger.removeHandler(log_handler.handler)
del log_handlers[token]
root_logger.debug("Removed log handler %s." % token)
return content
def get():
global root_logger
if root_logger is None:
root_logger = logging.getLogger("tuned")
calling_module = inspect.currentframe().f_back
name = calling_module.f_locals["__name__"]
if name == "__main__":
name = "tuned"
return root_logger
elif name.startswith("tuned."):
(root, child) = name.split(".", 1)
child_logger = root_logger.getChild(child)
child_logger.remove_all_handlers()
child_logger.setLevel("NOTSET")
return child_logger
else:
assert False
class TunedLogger(logging.getLoggerClass()):
"""Custom tuned daemon logger class."""
_formatter = logging.Formatter("%(asctime)s %(levelname)-8s %(name)s: %(message)s")
_console_handler = None
_file_handler = None
def __init__(self, *args, **kwargs):
super(TunedLogger, self).__init__(*args, **kwargs)
self.setLevel(logging.INFO)
self.switch_to_console()
def console(self, msg, *args, **kwargs):
self.log(consts.LOG_LEVEL_CONSOLE, msg, *args, **kwargs)
def switch_to_console(self):
self._setup_console_handler()
self.remove_all_handlers()
self.addHandler(self._console_handler)
def switch_to_file(self, filename = consts.LOG_FILE,
maxBytes = consts.LOG_FILE_MAXBYTES,
backupCount = consts.LOG_FILE_COUNT):
self._setup_file_handler(filename, maxBytes, backupCount)
self.remove_all_handlers()
self.addHandler(self._file_handler)
def remove_all_handlers(self):
_handlers = self.handlers
for handler in _handlers:
self.removeHandler(handler)
@classmethod
def _setup_console_handler(cls):
if cls._console_handler is not None:
return
cls._console_handler = logging.StreamHandler()
cls._console_handler.setFormatter(cls._formatter)
@classmethod
def _setup_file_handler(cls, filename, maxBytes, backupCount):
if cls._file_handler is not None:
return
log_directory = os.path.dirname(filename)
if log_directory == '':
log_directory = '.'
if not os.path.exists(log_directory):
os.makedirs(log_directory)
cls._file_handler = logging.handlers.RotatingFileHandler(
filename, maxBytes = int(maxBytes), backupCount = int(backupCount))
cls._file_handler.setFormatter(cls._formatter)
logging.addLevelName(consts.LOG_LEVEL_CONSOLE, consts.LOG_LEVEL_CONSOLE_NAME)
logging.setLoggerClass(TunedLogger)
atexit.register(logging.shutdown)