前段时间,我看到一个Mono应用程序的输出是彩色的,可能是因为它的日志系统(因为所有的消息都是标准化的)。
现在,Python有了日志记录模块,它允许您指定许多选项来定制输出。所以,我想象类似的事情可能与Python,但我不知道如何在任何地方做到这一点。
是否有办法使Python日志模块输出为彩色?
我想要的(例如)错误显示为红色,调试消息显示为蓝色或黄色,等等。
当然,这可能需要一个兼容的终端(大多数现代终端都是);但如果不支持颜色,我可以退回到原始的日志输出。
有什么想法,我可以得到彩色输出与日志模块?
我修改了Sorin提供的原始示例,并将StreamHandler子类化为ColorizedConsoleHandler。
他们的解决方案的缺点是它修改了消息,并且因为修改了实际的日志消息,任何其他处理程序也将得到修改后的消息。
在我们的例子中,这导致日志文件中有颜色代码,因为我们使用了多个记录器。
下面的类只在支持ANSI的平台上工作,但是向它添加Windows颜色代码应该很简单。
import copy
import logging
class ColoredConsoleHandler(logging.StreamHandler):
def emit(self, record):
# Need to make a actual copy of the record
# to prevent altering the message for other loggers
myrecord = copy.copy(record)
levelno = myrecord.levelno
if(levelno >= 50): # CRITICAL / FATAL
color = '\x1b[31m' # red
elif(levelno >= 40): # ERROR
color = '\x1b[31m' # red
elif(levelno >= 30): # WARNING
color = '\x1b[33m' # yellow
elif(levelno >= 20): # INFO
color = '\x1b[32m' # green
elif(levelno >= 10): # DEBUG
color = '\x1b[35m' # pink
else: # NOTSET and anything else
color = '\x1b[0m' # normal
myrecord.msg = color + str(myrecord.msg) + '\x1b[0m' # normal
logging.StreamHandler.emit(self, myrecord)
您可以导入colorlog模块,并使用它的ColoredFormatter对日志消息进行着色。
例子
主模块样板:
import logging
import os
import sys
try:
import colorlog
except ImportError:
pass
def setup_logging():
root = logging.getLogger()
root.setLevel(logging.DEBUG)
format = '%(asctime)s - %(levelname)-8s - %(message)s'
date_format = '%Y-%m-%d %H:%M:%S'
if 'colorlog' in sys.modules and os.isatty(2):
cformat = '%(log_color)s' + format
f = colorlog.ColoredFormatter(cformat, date_format,
log_colors = { 'DEBUG' : 'reset', 'INFO' : 'reset',
'WARNING' : 'bold_yellow', 'ERROR': 'bold_red',
'CRITICAL': 'bold_red' })
else:
f = logging.Formatter(format, date_format)
ch = logging.StreamHandler()
ch.setFormatter(f)
root.addHandler(ch)
setup_logging()
log = logging.getLogger(__name__)
该代码仅在安装了colorlog模块并且输出实际发送到终端时才启用日志消息中的颜色。这可以避免在日志输出重定向时将转义序列写入文件。
此外,还设置了一个自定义配色方案,更适合具有深色背景的终端。
一些日志调用示例:
log.debug ('Hello Debug')
log.info ('Hello Info')
log.warn ('Hello Warn')
log.error ('Hello Error')
log.critical('Hello Critical')
输出:
coloredlogs
Instalation
pip install coloredlogs
使用
最小的用法:
import logging
import coloredlogs
coloredlogs.install() # install a handler on the root logger
logging.debug('message with level debug')
logging.info('message with level info')
logging.warning('message with level warning')
logging.error('message with level error')
logging.critical('message with level critical')
结果:
从消息级调试开始:
import logging
import coloredlogs
coloredlogs.install(level='DEBUG') # install a handler on the root logger with level debug
logging.debug('message with level debug')
logging.info('message with level info')
logging.warning('message with level warning')
logging.error('message with level error')
logging.critical('message with level critical')
结果:
从库中隐藏消息:
import logging
import coloredlogs
logger = logging.getLogger(__name__) # get a specific logger object
coloredlogs.install(level='DEBUG') # install a handler on the root logger with level debug
coloredlogs.install(level='DEBUG', logger=logger) # pass a specific logger object
logging.debug('message with level debug')
logging.info('message with level info')
logging.warning('message with level warning')
logging.error('message with level error')
logging.critical('message with level critical')
结果:
格式化日志消息:
import logging
import coloredlogs
logger = logging.getLogger(__name__) # get a specific logger object
coloredlogs.install(level='DEBUG') # install a handler on the root logger with level debug
coloredlogs.install(level='DEBUG', logger=logger) # pass a specific logger object
coloredlogs.install(
level='DEBUG', logger=logger,
fmt='%(asctime)s.%(msecs)03d %(filename)s:%(lineno)d %(levelname)s %(message)s'
)
logging.debug('message with level debug')
logging.info('message with level info')
logging.warning('message with level warning')
logging.error('message with level error')
logging.critical('message with level critical')
结果:
可用的格式属性:
%(asctime)s - Time as human-readable string, when logging call was issued
%(created)f - Time as float when logging call was issued
%(filename)s - File name
%(funcName)s - Name of function containing the logging call
%(hostname)s - System hostname
%(levelname)s - Text logging level
%(levelno)s - Integer logging level
%(lineno)d - Line number where the logging call was issued
%(message)s - Message passed to logging call (same as %(msg)s)
%(module)s - File name without extension where the logging call was issued
%(msecs)d - Millisecond part of the time when logging call was issued
%(msg)s - Message passed to logging call (same as %(message)s)
%(name)s - Logger name
%(pathname)s - Full pathname to file containing the logging call
%(process)d - Process ID
%(processName)s - Process name
%(programname)s - System programname
%(relativeCreated)d - Time as integer in milliseconds when logging call was issued, relative to the time when logging module was loaded
%(thread)d - Thread ID
%(threadName)s - Thread name
%(username)s - System username
来源:
Coloredlogs包
日志库
另一个解决方案,用ZetaSyanthis的颜色:
def config_log(log_level):
def set_color(level, code):
level_fmt = "\033[1;" + str(code) + "m%s\033[1;0m"
logging.addLevelName( level, level_fmt % logging.getLevelName(level) )
std_stream = sys.stdout
isatty = getattr(std_stream, 'isatty', None)
if isatty and isatty():
levels = [logging.DEBUG, logging.CRITICAL, logging.WARNING, logging.ERROR]
for idx, level in enumerate(levels):
set_color(level, 30 + idx )
set_color(logging.DEBUG, 0)
logging.basicConfig(stream=std_stream, level=log_level)
在__main__函数中调用它一次。我这里有这样的东西:
options, arguments = p.parse_args()
log_level = logging.DEBUG if options.verbose else logging.WARNING
config_log(log_level)
它还验证输出是否为控制台,否则不使用颜色。