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?


当前回答

虽然其他解决方案看起来不错,但它们存在一些问题。有些人会给整条线上色,有时这是不需要的,有些人会省略你可能在一起的任何配置。下面的解决方案只影响消息本身。

Code

class ColoredFormatter(logging.Formatter):
    def format(self, record):
        if record.levelno == logging.WARNING:
            record.msg = '\033[93m%s\033[0m' % record.msg
        elif record.levelno == logging.ERROR:
            record.msg = '\033[91m%s\033[0m' % record.msg
        return logging.Formatter.format(self, record)

例子

logger = logging.getLogger('mylogger')
handler = logging.StreamHandler()

log_format = '[%(asctime)s]:%(levelname)-7s:%(message)s'
time_format = '%H:%M:%S'
formatter = ColoredFormatter(log_format, datefmt=time_format)
handler.setFormatter(formatter)
logger.addHandler(handler)

logger.warn('this should be yellow')
logger.error('this should be red')

输出

[17:01:36]:WARNING:this should be yellow
[17:01:37]:ERROR  :this should be red

如您所见,其他所有内容仍然输出并保持初始颜色。如果您想要更改消息以外的任何内容,您可以简单地将颜色代码传递给示例中的log_format。

其他回答

我遇到的麻烦是正确设置格式化程序:

class ColouredFormatter(logging.Formatter):    
    def __init__(self, msg):
        logging.Formatter.__init__(self, msg)
        self._init_colour = _get_colour()

    def close(self):
        # restore the colour information to what it was
        _set_colour(self._init_colour)

    def format(self, record):        
        # Add your own colourer based on the other examples
        _set_colour( LOG_LEVEL_COLOUR[record.levelno] )
        return logging.Formatter.format(self, record)         

def init():
    # Set up the formatter. Needs to be first thing done.
    rootLogger = logging.getLogger()
    hdlr = logging.StreamHandler()
    fmt = ColouredFormatter('%(message)s')
    hdlr.setFormatter(fmt)
    rootLogger.addHandler(hdlr)

然后使用:

import coloured_log
import logging

coloured_log.init()
logging.info("info")    
logging.debug("debug")    

coloured_log.close()    # restore colours

以下是我的解决方案:

class ColouredFormatter(logging.Formatter):
    RESET = '\x1B[0m'
    RED = '\x1B[31m'
    YELLOW = '\x1B[33m'
    BRGREEN = '\x1B[01;32m'  # grey in solarized for terminals

    def format(self, record, colour=False):
        message = super().format(record)

        if not colour:
            return message

        level_no = record.levelno
        if level_no >= logging.CRITICAL:
            colour = self.RED
        elif level_no >= logging.ERROR:
            colour = self.RED
        elif level_no >= logging.WARNING:
            colour = self.YELLOW
        elif level_no >= logging.INFO:
            colour = self.RESET
        elif level_no >= logging.DEBUG:
            colour = self.BRGREEN
        else:
            colour = self.RESET

        message = colour + message + self.RESET

        return message


class ColouredHandler(logging.StreamHandler):
    def __init__(self, stream=sys.stdout):
        super().__init__(stream)

    def format(self, record, colour=False):
        if not isinstance(self.formatter, ColouredFormatter):
            self.formatter = ColouredFormatter()

        return self.formatter.format(record, colour)

    def emit(self, record):
        stream = self.stream
        try:
            msg = self.format(record, stream.isatty())
            stream.write(msg)
            stream.write(self.terminator)
            self.flush()
        except Exception:
            self.handleError(record)


h = ColouredHandler()
h.formatter = ColouredFormatter('{asctime} {levelname:8} {message}', '%Y-%m-%d %H:%M:%S', '{')
logging.basicConfig(level=logging.DEBUG, handlers=[h])

虽然其他解决方案看起来不错,但它们存在一些问题。有些人会给整条线上色,有时这是不需要的,有些人会省略你可能在一起的任何配置。下面的解决方案只影响消息本身。

Code

class ColoredFormatter(logging.Formatter):
    def format(self, record):
        if record.levelno == logging.WARNING:
            record.msg = '\033[93m%s\033[0m' % record.msg
        elif record.levelno == logging.ERROR:
            record.msg = '\033[91m%s\033[0m' % record.msg
        return logging.Formatter.format(self, record)

例子

logger = logging.getLogger('mylogger')
handler = logging.StreamHandler()

log_format = '[%(asctime)s]:%(levelname)-7s:%(message)s'
time_format = '%H:%M:%S'
formatter = ColoredFormatter(log_format, datefmt=time_format)
handler.setFormatter(formatter)
logger.addHandler(handler)

logger.warn('this should be yellow')
logger.error('this should be red')

输出

[17:01:36]:WARNING:this should be yellow
[17:01:37]:ERROR  :this should be red

如您所见,其他所有内容仍然输出并保持初始颜色。如果您想要更改消息以外的任何内容,您可以简单地将颜色代码传递给示例中的log_format。

我更喜欢使用这个片段:

import logging
from enum import Enum

CSI = '\033['

Color = Enum(
    'Color', 'BLACK RED GREEN YELLOW BLUE MAGENTA CYAN WHITE', start=30
)


class AnsiColorHandler(logging.StreamHandler):
    LOGLEVEL_COLORS = {
        'DEBUG': Color.BLUE,
        'INFO': Color.GREEN,
        'WARNING': Color.RED,
        'ERROR': Color.RED,
        'CRITICAL': Color.RED,
    }

    def __init__(self) -> None:
        super().__init__()
        self.formatter = logging.Formatter("%(levelname)-8s - %(message)s")

    def format(self, record: logging.LogRecord) -> str:
        message: str = super().format(record)
        # use colors in tty
        if self.stream.isatty() and (
            color := self.LOGLEVEL_COLORS.get(record.levelname)
        ):
            message = f'{CSI}{color.value}m{message}{CSI}0m'
        return message


# setup logger
# logger = logging.getLogger(__package__)
logger = logging.getLogger(__name__)
logger.addHandler(AnsiColorHandler())

用法:

import logging

from .log import logger

logger.setLevel(logging.DEBUG)
logger.debug("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa")

FriendlyLog是另一种选择。它适用于Linux、Windows和MacOS下的Python 2和3。