下面是一种基于强大但缺乏文档记录的logging.config.dictConfig方法的解决方案。 它不是将每个日志消息发送到stdout，而是将日志级别为ERROR或更高的消息发送到stderr，将其他所有消息发送到stdout。 如果系统的其他部分正在侦听stderr或stdout，这可能很有用。

import logging
import logging.config
import sys

class _ExcludeErrorsFilter(logging.Filter):
    def filter(self, record):
        """Only lets through log messages with log level below ERROR ."""
        return record.levelno < logging.ERROR


config = {
    'version': 1,
    'filters': {
        'exclude_errors': {
            '()': _ExcludeErrorsFilter
        }
    },
    'formatters': {
        # Modify log message format here or replace with your custom formatter class
        'my_formatter': {
            'format': '(%(process)d) %(asctime)s %(name)s (line %(lineno)s) | %(levelname)s %(message)s'
        }
    },
    'handlers': {
        'console_stderr': {
            # Sends log messages with log level ERROR or higher to stderr
            'class': 'logging.StreamHandler',
            'level': 'ERROR',
            'formatter': 'my_formatter',
            'stream': sys.stderr
        },
        'console_stdout': {
            # Sends log messages with log level lower than ERROR to stdout
            'class': 'logging.StreamHandler',
            'level': 'DEBUG',
            'formatter': 'my_formatter',
            'filters': ['exclude_errors'],
            'stream': sys.stdout
        },
        'file': {
            # Sends all log messages to a file
            'class': 'logging.FileHandler',
            'level': 'DEBUG',
            'formatter': 'my_formatter',
            'filename': 'my.log',
            'encoding': 'utf8'
        }
    },
    'root': {
        # In general, this should be kept at 'NOTSET'.
        # Otherwise it would interfere with the log levels set for each handler.
        'level': 'NOTSET',
        'handlers': ['console_stderr', 'console_stdout', 'file']
    },
}

logging.config.dictConfig(config)

所有日志输出都由处理程序处理;只需将logging.StreamHandler()添加到根日志记录器。

下面是一个配置流处理程序的例子(使用stdout而不是默认的stderr)，并将其添加到根日志记录器:

import logging
import sys

root = logging.getLogger()
root.setLevel(logging.DEBUG)

handler = logging.StreamHandler(sys.stdout)
handler.setLevel(logging.DEBUG)
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
handler.setFormatter(formatter)
root.addHandler(handler)

这里有一个非常简单的例子:

import logging
l = logging.getLogger("test")

# Add a file logger
f = logging.FileHandler("test.log")
l.addHandler(f)

# Add a stream logger
s = logging.StreamHandler()
l.addHandler(s)

# Send a test message to both -- critical will always log
l.critical("test msg")

输出将在stdout和文件中显示“test msg”。

如需更详细的解释，请在该链接中查阅相关文档。 这很简单，你只需要设置两个记录器。

import sys
import logging

logger = logging.getLogger('')
logger.setLevel(logging.DEBUG)
fh = logging.FileHandler('my_log_info.log')
sh = logging.StreamHandler(sys.stdout)
formatter = logging.Formatter('[%(asctime)s] %(levelname)s [%(filename)s.%(funcName)s:%(lineno)d] %(message)s', datefmt='%a, %d %b %Y %H:%M:%S')
fh.setFormatter(formatter)
sh.setFormatter(formatter)
logger.addHandler(fh)
logger.addHandler(sh)

def hello_logger():
    logger.info("Hello info")
    logger.critical("Hello critical")
    logger.warning("Hello warning")
    logger.debug("Hello debug")

if __name__ == "__main__":
    print(hello_logger())

输出端:

[Mon, 10 Aug 2020 12:44:25] INFO [TestLoger.py.hello_logger:15] Hello info
[Mon, 10 Aug 2020 12:44:25] CRITICAL [TestLoger.py.hello_logger:16] Hello critical
[Mon, 10 Aug 2020 12:44:25] WARNING [TestLoger.py.hello_logger:17] Hello warning
[Mon, 10 Aug 2020 12:44:25] DEBUG [TestLoger.py.hello_logger:18] Hello debug
None

输出文件:

更新:彩色终端

包:

pip install colorlog

代码:

import sys
import logging
import colorlog

logger = logging.getLogger('')
logger.setLevel(logging.DEBUG)
fh = logging.FileHandler('my_log_info.log')
sh = logging.StreamHandler(sys.stdout)
formatter = logging.Formatter('[%(asctime)s] %(levelname)s [%(filename)s.%(funcName)s:%(lineno)d] %(message)s', datefmt='%a, %d %b %Y %H:%M:%S')
fh.setFormatter(formatter)
sh.setFormatter(colorlog.ColoredFormatter('%(log_color)s [%(asctime)s] %(levelname)s [%(filename)s.%(funcName)s:%(lineno)d] %(message)s', datefmt='%a, %d %b %Y %H:%M:%S'))
logger.addHandler(fh)
logger.addHandler(sh)

def hello_logger():
    logger.info("Hello info")
    logger.critical("Hello critical")
    logger.warning("Hello warning")
    logger.debug("Hello debug")
    logger.error("Error message")

if __name__ == "__main__":
    hello_logger()

输出:

推荐:

INI文件中完整的记录器配置，其中还包括stdout和debug.log的设置:

handler_file 级别=警告 handler_screen 水平=调试

你应该用t。配置应用程序写入标准输出，并运行

python3 app.py | tee log.txt

然后您将在stdout和log.txt中获得日志消息。

可以使用多个处理程序。

import logging
import auxiliary_module

# create logger with 'spam_application'
log = logging.getLogger('spam_application')
log.setLevel(logging.DEBUG)

# create formatter and add it to the handlers
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')

# create file handler which logs even debug messages
fh = logging.FileHandler('spam.log')
fh.setLevel(logging.DEBUG)
fh.setFormatter(formatter)
log.addHandler(fh)

# create console handler with a higher log level
ch = logging.StreamHandler()
ch.setLevel(logging.ERROR)
ch.setFormatter(formatter)
log.addHandler(ch)

log.info('creating an instance of auxiliary_module.Auxiliary')
a = auxiliary_module.Auxiliary()
log.info('created an instance of auxiliary_module.Auxiliary')

log.info('calling auxiliary_module.Auxiliary.do_something')
a.do_something()
log.info('finished auxiliary_module.Auxiliary.do_something')

log.info('calling auxiliary_module.some_function()')
auxiliary_module.some_function()
log.info('done with auxiliary_module.some_function()')

# remember to close the handlers
for handler in log.handlers:
    handler.close()
    log.removeFilter(handler)

请参阅:https://docs.python.org/2/howto/logging-cookbook.html