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

除了按级别着色之外,还可以用交替的颜色突出显示日志消息参数吗?我最近为此写了一些简单的代码。另一个优点是使用Python 3大括号格式进行日志调用。(“{}”)。

查看最新的代码和示例:https://github.com/davidohana/colargulog

日志示例代码:

root_logger = logging.getLogger()
console_handler = logging.StreamHandler(stream=sys.stdout)
console_format = "%(asctime)s - %(levelname)-8s - %(name)-25s - %(message)s"
colored_formatter = ColorizedArgsFormatter(console_format)
console_handler.setFormatter(colored_formatter)
root_logger.addHandler(console_handler)

logger = logging.getLogger(__name__)
logger.info("Hello World")
logger.info("Request from {} handled in {:.3f} ms", socket.gethostname(), 11)
logger.info("Request from {} handled in {:.3f} ms", "127.0.0.1", 33.1)
logger.info("My favorite drinks are {}, {}, {}, {}", "milk", "wine", "tea", "beer")
logger.debug("this is a {} message", logging.getLevelName(logging.DEBUG))
logger.info("this is a {} message", logging.getLevelName(logging.INFO))
logger.warning("this is a {} message", logging.getLevelName(logging.WARNING))
logger.error("this is a {} message", logging.getLevelName(logging.ERROR))
logger.critical("this is a {} message", logging.getLevelName(logging.CRITICAL))
logger.info("Does old-style formatting also work? %s it is, but no colors (yet)", True)

输出:

实现:

"""
colargulog - Python3 Logging with Colored Arguments and new string formatting style

Written by david.ohana@ibm.com
License: Apache-2.0
"""

import logging
import logging.handlers
import re


class ColorCodes:
    grey = "\x1b[38;21m"
    green = "\x1b[1;32m"
    yellow = "\x1b[33;21m"
    red = "\x1b[31;21m"
    bold_red = "\x1b[31;1m"
    blue = "\x1b[1;34m"
    light_blue = "\x1b[1;36m"
    purple = "\x1b[1;35m"
    reset = "\x1b[0m"


class ColorizedArgsFormatter(logging.Formatter):
    arg_colors = [ColorCodes.purple, ColorCodes.light_blue]
    level_fields = ["levelname", "levelno"]
    level_to_color = {
        logging.DEBUG: ColorCodes.grey,
        logging.INFO: ColorCodes.green,
        logging.WARNING: ColorCodes.yellow,
        logging.ERROR: ColorCodes.red,
        logging.CRITICAL: ColorCodes.bold_red,
    }

    def __init__(self, fmt: str):
        super().__init__()
        self.level_to_formatter = {}

        def add_color_format(level: int):
            color = ColorizedArgsFormatter.level_to_color[level]
            _format = fmt
            for fld in ColorizedArgsFormatter.level_fields:
                search = "(%\(" + fld + "\).*?s)"
                _format = re.sub(search, f"{color}\\1{ColorCodes.reset}", _format)
            formatter = logging.Formatter(_format)
            self.level_to_formatter[level] = formatter

        add_color_format(logging.DEBUG)
        add_color_format(logging.INFO)
        add_color_format(logging.WARNING)
        add_color_format(logging.ERROR)
        add_color_format(logging.CRITICAL)

    @staticmethod
    def rewrite_record(record: logging.LogRecord):
        if not BraceFormatStyleFormatter.is_brace_format_style(record):
            return

        msg = record.msg
        msg = msg.replace("{", "_{{")
        msg = msg.replace("}", "_}}")
        placeholder_count = 0
        # add ANSI escape code for next alternating color before each formatting parameter
        # and reset color after it.
        while True:
            if "_{{" not in msg:
                break
            color_index = placeholder_count % len(ColorizedArgsFormatter.arg_colors)
            color = ColorizedArgsFormatter.arg_colors[color_index]
            msg = msg.replace("_{{", color + "{", 1)
            msg = msg.replace("_}}", "}" + ColorCodes.reset, 1)
            placeholder_count += 1

        record.msg = msg.format(*record.args)
        record.args = []

    def format(self, record):
        orig_msg = record.msg
        orig_args = record.args
        formatter = self.level_to_formatter.get(record.levelno)
        self.rewrite_record(record)
        formatted = formatter.format(record)

        # restore log record to original state for other handlers
        record.msg = orig_msg
        record.args = orig_args
        return formatted


class BraceFormatStyleFormatter(logging.Formatter):
    def __init__(self, fmt: str):
        super().__init__()
        self.formatter = logging.Formatter(fmt)

    @staticmethod
    def is_brace_format_style(record: logging.LogRecord):
        if len(record.args) == 0:
            return False

        msg = record.msg
        if '%' in msg:
            return False

        count_of_start_param = msg.count("{")
        count_of_end_param = msg.count("}")

        if count_of_start_param != count_of_end_param:
            return False

        if count_of_start_param != len(record.args):
            return False

        return True

    @staticmethod
    def rewrite_record(record: logging.LogRecord):
        if not BraceFormatStyleFormatter.is_brace_format_style(record):
            return

        record.msg = record.msg.format(*record.args)
        record.args = []

    def format(self, record):
        orig_msg = record.msg
        orig_args = record.args
        self.rewrite_record(record)
        formatted = self.formatter.format(record)

        # restore log record to original state for other handlers
        record.msg = orig_msg
        record.args = orig_args
        return formatted

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:

一个方便的带有tput颜色的bash脚本

# Simple using tput
bold=$(tput bold)
reset=$(tput sgr0)

fblack=$(tput setaf 0)
fred=$(tput setaf 1)
fgreen=$(tput setaf 2)
fyellow=$(tput setaf 3)
fblue=$(tput setaf 4)
fmagenta=$(tput setaf 5)
fcyan=$(tput setaf 6)
fwhite=$(tput setaf 7)
fnotused=$(tput setaf 8)
freset=$(tput setaf 9)

bblack=$(tput setab 0)
bred=$(tput setab 1)
bgreen=$(tput setab 2)
byellow=$(tput setab 3)
bblue=$(tput setab 4)
bmagenta=$(tput setab 5)
bcyan=$(tput setab 6)
bwhite=$(tput setab 7)
bnotused=$(tput setab 8)
breset=$(tput setab 9)

# 0 - Emergency (emerg)       $fred       # something is wrong... go red
# 1 - Alerts (alert)          $fred       # something is wrong... go red
# 2 - Critical (crit)         $fred       # something is wrong... go red
# 3 - Errors (err)            $fred       # something is wrong... go red
# 4 - Warnings (warn)         $fyellow    # yellow yellow dirty logs
# 5 - Notification (notice)   $fwhite     # common stuff
# 6 - Information (info)      $fblue      # sky is blue
# 7 - Debug (debug)           $fgreen     # lot of stuff to read... go green 

刚刚回答了类似的问题:Python |在shell中更改文本颜色

这个想法是使用clint库。它支持MAC, Linux和Windows shell (CLI)。

一个简单但非常灵活的工具为任何终端文本着色是'colout'。

pip install colout
myprocess | colout REGEX_WITH_GROUPS color1,color2...

其中'myprocess'输出中的任何匹配正则表达式第1组的文本都将用color1着色,第2组用color2着色,等等。

例如:

tail -f /var/log/mylogfile | colout '^(\w+ \d+ [\d:]+)|(\w+\.py:\d+ .+\(\)): (.+)$' white,black,cyan bold,bold,normal

也就是说,第一个正则表达式组(parens)匹配日志文件中的初始日期,第二组匹配python文件名、行号和函数名,第三组匹配其后的日志消息。我还使用了“粗体/法线”的平行序列以及颜色序列。这看起来像:

请注意,不匹配任何正则表达式的行或行的一部分仍然被回显,因此这与'grep——color'不同——输出中没有过滤掉任何内容。

显然,这是足够灵活的,您可以将它用于任何进程,而不仅仅是跟踪日志文件。每当我想给一些东西上色时,我通常只是快速地创建一个新的正则表达式。出于这个原因,我更喜欢colout而不是任何自定义日志文件着色工具,因为我只需要学习一种工具,不管我在为什么着色:日志记录、测试输出、在终端中突出显示代码片段的语法等等。

它还避免了在日志文件本身中实际转储ANSI代码,恕我说这是一个坏主意,因为它会破坏日志文件中的grepping模式之类的事情,除非您始终记得在grep正则表达式中匹配ANSI代码。

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