bootstrap-vz/bootstrapvz/base/log.py
2015-04-16 22:15:17 +02:00

119 lines
3.7 KiB
Python

"""This module holds functions and classes responsible for formatting the log output
both to a file and to the console.
"""
import logging
def get_console_handler(debug, colorize):
"""Returns a log handler for the console
The handler color codes the different log levels
:params bool debug: Whether to set the log level to DEBUG (otherwise INFO)
:params bool colorize: Whether to colorize console output
:return: The console logging handler
"""
# Create a console log handler
import sys
console_handler = logging.StreamHandler(sys.stderr)
if colorize:
# We want to colorize the output to the console, so we add a formatter
console_handler.setFormatter(ConsoleFormatter())
# Set the log level depending on the debug argument
if debug:
console_handler.setLevel(logging.DEBUG)
else:
console_handler.setLevel(logging.INFO)
return console_handler
def get_file_handler(path, debug):
"""Returns a log handler for the given path
If the parent directory of the logpath does not exist it will be created
The handler outputs relative timestamps (to when it was created)
:params str path: The full path to the logfile
:params bool debug: Whether to set the log level to DEBUG (otherwise INFO)
:return: The file logging handler
"""
import os.path
if not os.path.exists(os.path.dirname(path)):
os.makedirs(os.path.dirname(path))
# Create the log handler
file_handler = logging.FileHandler(path)
# Absolute timestamps are rather useless when bootstrapping, it's much more interesting
# to see how long things take, so we log in a relative format instead
file_handler.setFormatter(FileFormatter('[%(relativeCreated)s] %(levelname)s: %(message)s'))
# The file log handler always logs everything
file_handler.setLevel(logging.DEBUG)
return file_handler
def get_log_filename(manifest_path):
"""Returns the path to a logfile given a manifest
The logfile name is constructed from the current timestamp and the basename of the manifest
:param str manifest_path: The path to the manifest
:return: The path to the logfile
:rtype: str
"""
import os.path
from datetime import datetime
manifest_basename = os.path.basename(manifest_path)
manifest_name, _ = os.path.splitext(manifest_basename)
timestamp = datetime.now().strftime('%Y%m%d%H%M%S')
filename = '{timestamp}_{name}.log'.format(timestamp=timestamp, name=manifest_name)
return filename
class ConsoleFormatter(logging.Formatter):
"""Formats log statements for the console
"""
level_colors = {logging.ERROR: 'red',
logging.WARNING: 'magenta',
logging.INFO: 'blue',
}
def format(self, record):
if(record.levelno in self.level_colors):
# Colorize the message if we have a color for it (DEBUG has no color)
from termcolor import colored
record.msg = colored(record.msg, self.level_colors[record.levelno])
return super(ConsoleFormatter, self).format(record)
class FileFormatter(logging.Formatter):
"""Formats log statements for output to file
Currently this is just a stub
"""
def format(self, record):
return super(FileFormatter, self).format(record)
class LogForwarder(logging.Handler):
def __init__(self, level=logging.NOTSET):
self.server = None
super(LogForwarder, self).__init__(level)
def set_server(self, server):
self.server = server
def emit(self, record):
if self.server is not None:
if record.exc_info is not None:
import traceback
exc_type, exc_value, exc_traceback = record.exc_info
record.exc_info = traceback.print_exception(exc_type, exc_value, exc_traceback)
# TODO: Use serpent instead
import pickle
self.server.handle(pickle.dumps(record))
class LogServer(object):
def handle(self, pickled_record):
import pickle
record = pickle.loads(pickled_record)
log = logging.getLogger()
log.handle(record)