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

airmind的另一种方法是将所有东西都放在一个类中:

class ColorFormatter(logging.Formatter):
  FORMAT = ("[$BOLD%(name)-20s$RESET][%(levelname)-18s]  "
            "%(message)s "
            "($BOLD%(filename)s$RESET:%(lineno)d)")

  BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE = range(8)

  RESET_SEQ = "\033[0m"
  COLOR_SEQ = "\033[1;%dm"
  BOLD_SEQ = "\033[1m"

  COLORS = {
    'WARNING': YELLOW,
    'INFO': WHITE,
    'DEBUG': BLUE,
    'CRITICAL': YELLOW,
    'ERROR': RED
  }

  def formatter_msg(self, msg, use_color = True):
    if use_color:
      msg = msg.replace("$RESET", self.RESET_SEQ).replace("$BOLD", self.BOLD_SEQ)
    else:
      msg = msg.replace("$RESET", "").replace("$BOLD", "")
    return msg

  def __init__(self, use_color=True):
    msg = self.formatter_msg(self.FORMAT, use_color)
    logging.Formatter.__init__(self, msg)
    self.use_color = use_color

  def format(self, record):
    levelname = record.levelname
    if self.use_color and levelname in self.COLORS:
      fore_color = 30 + self.COLORS[levelname]
      levelname_color = self.COLOR_SEQ % fore_color + levelname + self.RESET_SEQ
      record.levelname = levelname_color
    return logging.Formatter.format(self, record)

要使用将格式化程序附加到处理程序,如下所示:

handler.setFormatter(ColorFormatter())
logger.addHandler(handler)

其他回答

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:

我从airmind中更新了支持前景和背景标签的示例。 只需在日志格式化器字符串中使用颜色变量$BLACK - $WHITE即可。设置背景只需使用$BG-BLACK - $BG-WHITE。

import logging

BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE = range(8)

COLORS = {
    'WARNING'  : YELLOW,
    'INFO'     : WHITE,
    'DEBUG'    : BLUE,
    'CRITICAL' : YELLOW,
    'ERROR'    : RED,
    'RED'      : RED,
    'GREEN'    : GREEN,
    'YELLOW'   : YELLOW,
    'BLUE'     : BLUE,
    'MAGENTA'  : MAGENTA,
    'CYAN'     : CYAN,
    'WHITE'    : WHITE,
}

RESET_SEQ = "\033[0m"
COLOR_SEQ = "\033[1;%dm"
BOLD_SEQ  = "\033[1m"

class ColorFormatter(logging.Formatter):

    def __init__(self, *args, **kwargs):
        # can't do super(...) here because Formatter is an old school class
        logging.Formatter.__init__(self, *args, **kwargs)

    def format(self, record):
        levelname = record.levelname
        color     = COLOR_SEQ % (30 + COLORS[levelname])
        message   = logging.Formatter.format(self, record)
        message   = message.replace("$RESET", RESET_SEQ)\
                           .replace("$BOLD",  BOLD_SEQ)\
                           .replace("$COLOR", color)
        for k,v in COLORS.items():
            message = message.replace("$" + k,    COLOR_SEQ % (v+30))\
                             .replace("$BG" + k,  COLOR_SEQ % (v+40))\
                             .replace("$BG-" + k, COLOR_SEQ % (v+40))
        return message + RESET_SEQ

logging.ColorFormatter = ColorFormatter

所以现在你可以在配置文件中简单地执行以下操作:

[formatter_colorFormatter]
class=logging.ColorFormatter
format= $COLOR%(levelname)s $RESET %(asctime)s $BOLD$COLOR%(name)s$RESET %(message)s

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])

airmind的另一种方法是将所有东西都放在一个类中:

class ColorFormatter(logging.Formatter):
  FORMAT = ("[$BOLD%(name)-20s$RESET][%(levelname)-18s]  "
            "%(message)s "
            "($BOLD%(filename)s$RESET:%(lineno)d)")

  BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE = range(8)

  RESET_SEQ = "\033[0m"
  COLOR_SEQ = "\033[1;%dm"
  BOLD_SEQ = "\033[1m"

  COLORS = {
    'WARNING': YELLOW,
    'INFO': WHITE,
    'DEBUG': BLUE,
    'CRITICAL': YELLOW,
    'ERROR': RED
  }

  def formatter_msg(self, msg, use_color = True):
    if use_color:
      msg = msg.replace("$RESET", self.RESET_SEQ).replace("$BOLD", self.BOLD_SEQ)
    else:
      msg = msg.replace("$RESET", "").replace("$BOLD", "")
    return msg

  def __init__(self, use_color=True):
    msg = self.formatter_msg(self.FORMAT, use_color)
    logging.Formatter.__init__(self, msg)
    self.use_color = use_color

  def format(self, record):
    levelname = record.levelname
    if self.use_color and levelname in self.COLORS:
      fore_color = 30 + self.COLORS[levelname]
      levelname_color = self.COLOR_SEQ % fore_color + levelname + self.RESET_SEQ
      record.levelname = levelname_color
    return logging.Formatter.format(self, record)

要使用将格式化程序附加到处理程序,如下所示:

handler.setFormatter(ColorFormatter())
logger.addHandler(handler)

这是@Sergey Pleshakov的出色回答的轻微变化,他只对关卡使用颜色,并像预期的那样使用basicConfig:

class CustomFormatter(logging.Formatter):

    white = "\x1b[97;20m"
    grey = "\x1b[38;20m"
    green = "\x1b[32;20m"
    cyan = "\x1b[36;20m"
    yellow = "\x1b[33;20m"
    red = "\x1b[31;20m"
    bold_red = "\x1b[31;1m"
    reset = "\x1b[0m"
    fmt = "%(asctime)s - {}%(levelname)-8s{} - %(name)s.%(funcName)s - %(message)s"

    FORMATS = {
        logging.DEBUG: fmt.format(grey, reset),
        logging.INFO: fmt.format(green, reset),
        logging.WARNING: fmt.format(yellow, reset),
        logging.ERROR: fmt.format(red, reset),
        logging.CRITICAL: fmt.format(bold_red, reset),
    }

    def format(self, record):
        log_fmt = self.FORMATS.get(record.levelno)
        formatter = logging.Formatter(log_fmt, datefmt="%H:%M:%S")
        return formatter.format(record)


handler = logging.StreamHandler()
handler.setFormatter(CustomFormatter())
logging.basicConfig(
    level=logging.DEBUG,
    handlers=[handler]
)