除日志文件外，使Python Logger 还将所有消息输出到stdout

7 回答

• 458

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

  以下是配置流处理程序（使用 stdout 而不是默认 stderr ）并将其添加到根 Logger 的示例：

  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)
  

  回复于 2024-05-04T10:47:04+08:00
• 29

  最简单的方法：

  import logging
  import sys
  logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
  

  回复于 2024-05-04T10:47:04+08:00
• 48

  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

  回复于 2024-05-04T10:47:04+08:00
• 0

  您可以为file和stdout创建两个处理程序，然后使用 handlers 参数为basicConfig创建一个 Logger . 如果两个处理程序具有相同的log_level和format输出，那么它可能很有用：

  import logging
  import sys
  
  file_handler = logging.FileHandler(filename='tmp.log')
  stdout_handler = logging.StreamHandler(sys.stdout)
  handlers = [file_handler, stdout_handler]
  
  logging.basicConfig(
      level=logging.DEBUG, 
      format='[%(asctime)s] {%(filename)s:%(lineno)d} %(levelname)s - %(message)s',
      handlers=handlers
  )
  
  logger = logging.getLogger('LOGGER_NAME')
  

  回复于 2024-05-04T10:47:04+08:00
• 32

  记录到文件和stderr的最简单方法：

  import logging
    logging.basicConfig(filename="logfile.txt")
    stderrLogger=logging.StreamHandler()
    stderrLogger.setFormatter(logging.Formatter(logging.BASIC_FORMAT))
    logging.getLogger().addHandler(stderrLogger)
  

  回复于 2024-05-04T10:47:04+08:00
• 362

  这是基于dictConfig configuration function的解决方案 . 它不是将每条日志消息发送到stdout，而是将日志级别为ERROR且更高的消息发送到stderr，将其他所有内容发送到stdout . 如果系统的其他部分正在侦听stderr / stdout，这可能很有用 .

  import logging
  import logging.config
  import sys
  
  class _ExcludeErrorsFilter(logging.Filter):
      def filter(self, record):
          """Filters out log messages with log level ERROR (numeric value: 40) or higher."""
          return record.levelno < 40
  
  
  config = {
      'version': 1,
      'filters': {
          'exclude_errors': {
              '()': _ExcludeErrorsFilter
          }
      },
      'formatters': {
          'my_formatter': {
              'format': '(%(process)d) %(asctime)s %(name)s (line %(lineno)s) | %(levelname)s %(message)s'
          }
      },
      'handlers': {
          'console_stderr': {
              # Directs log messages with log level ERROR or higher to stderr
              'class': 'logging.StreamHandler',
              'level': 'ERROR',
              'formatter': 'my_formatter',
              'stream': sys.stderr
          },
          'console_stdout': {
              # Directs 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': {
              # Directs all log messages to a file
              'class': 'logging.FileHandler',
              'level': 'DEBUG',
              'formatter': 'my_formatter',
              'filename': 'my.log',
              'encoding': 'utf8'
          }
      },
      'root': {
          'level': 'NOTSET',
          'handlers': ['console_stderr', 'console_stdout', 'file']
      },
  }
  
  logging.config.dictConfig(config)
  

  回复于 2024-05-04T10:47:04+08:00
• 0

  看一下loguru模块 .

  from loguru import logger
  
  logger.debug("That's it, beautiful and simple logging!")
  

  回复于 2024-05-04T10:47:04+08:00