python-3.x - 如何在记录 python 时使用可调用对象作为过滤器

Question

我不知道如何使用这个new property python3.2的。在那里，可以使用可调用对象而不是实现 logging.Filter 类。

• 我正在尝试使用 dictConfig对于我的记录器(在 python 中)。在那，我想添加一个过滤器，如果记录的消息包含特定短语，它就会通过。
• 我知道如何通过实现 logging.Filter 类来做到这一点。
• 但我不知道如何只使用 python 3.2 的可调用“奇特”属性，如所述 here

好的代码在这里

class ignore_progress(logging.Filter):
    def filter(self, record):

        return not ('Progress' in record.getMessage())
class log_progress(logging.Filter):
    def filter(self, record):
        return ('Progress' in record.getMessage())
def contain_progress(record):
    return not ('Progress' in record.message)
logging_dict = {
    "version": 1,
    "disable_existing_loggers": False,  
    "formatters": {
        "standard": {
            "format": "%(asctime)s [%(levelname)s] %(name)s: %(message)s",
        }
    },
    "filters": {
         "ignore_progress": {
            '()': ignore_progress,
        }
    },
    "handlers": {
        "default": {
            "class": "logging.StreamHandler",
            "level": "DEBUG",
            "formatter": "standard",
        },
        "file": {
            "class": "logging.FileHandler",
            "level": "DEBUG",
            "formatter": "standard",
            "filename": 'training_{}.log'.format(str(datetime.date.today())),
            "filters": ["ignore_progress"],
        },
    },
    "loggers": {
        "": {"handlers": ["default", "file"], "level": "DEBUG", "propagate": True, },
    },
}
# Configurate the logger
logging.config.dictConfig(logging_dict)
logger = logging.getLogger(__name__)

logger.info("Run training")
logger.info("Progress.test")

这里有错误的代码

class ignore_progress(logging.Filter):
    def filter(self, record):

        return not ('Progress' in record.getMessage())
class log_progress(logging.Filter):
    def filter(self, record):
        return ('Progress' in record.getMessage())
def contain_progress(record):
    return not ('Progress' in record.message)
logging_dict = {
    "version": 1,
    "disable_existing_loggers": False,  
    "formatters": {
        "standard": {
            "format": "%(asctime)s [%(levelname)s] %(name)s: %(message)s",
        }
    },
    "filters": {
         "ignore_progress": {
            '()': contain_progress,
        }
    },
    "handlers": {
        "default": {
            "class": "logging.StreamHandler",
            "level": "DEBUG",
            "formatter": "standard",
        },
        "file": {
            "class": "logging.FileHandler",
            "level": "DEBUG",
            "formatter": "standard",
            "filename": 'training_{}.log'.format(str(datetime.date.today())),
            "filters": ["ignore_progress"],
        },
    },
    "loggers": {
        "": {"handlers": ["default", "file"], "level": "DEBUG", "propagate": True, },
    },
}
# Configurate the logger
logging.config.dictConfig(logging_dict)
logger = logging.getLogger(__name__)

logger.info("Run training")
logger.info("Progress.test")

上面的错误代码在这个line处有问题在 config.py

中

Answer 1

当在 dictConfig 中使用 Callable 时，您放入 dictConfig 值中的 Callable 必须是一个 Callable，它返回一个 Callable，如 Python Bug Tracker 中所讨论的:

• https://bugs.python.org/issue41906

例如

def my_filter_wrapper():
    # the returned Callable has to accept a single argument (the LogRecord instance passed in this callable) with return value of 1 or 0
    return lambda record: 0 if <your_condition_here> else 1

logging_dict = {
    ...
    'filters': {
         'ignore_progress': {
            '()': my_filter_wrapper,
        }
    },
    ...

如果您的自定义过滤逻辑是单行的并且独立于日志记录实例，则更简单:

logging_dict = {
    ...
    'filters': {
         'ignore_progress': {
            '()': lambda : lambda _: 0 if <your_condition> else 1
        }
    },
    ...

我花了很长时间才弄明白这一点。希望它能帮助任何有同样问题的人。

而且在其 Python 实现中肯定需要一些东西来使其更加优雅。