使用 YAML 和过滤器登录 python

想要使用 YAML 设置带有过滤器的记录器。

YAML 配置文件config.yaml如下：

version: 1

formatters:
  simple:
    format: "%(asctime)s %(name)s: %(message)s"
  extended:
    format: "%(asctime)s %(name)s %(levelname)s: %(message)s"

filters:
  noConsoleFilter:
    class: noConsoleFilter

handlers:
  console:
    class: logging.StreamHandler
    level: INFO
    formatter: simple
    filters: [noConsoleFilter]

  file_handler:
    class: logging.FileHandler
    level: INFO
    filename: test.log
    formatter: extended

root:
  handlers: [console, file_handler]
  propagate: true

...以及主程序main.py如下：

import logging.config
import yaml

class noConsoleFilter(logging.Filter):
    def filter(self, record):
        print("filtering!")
        return not (record.levelname == 'INFO') & ('no-console' in record.msg)

with open('config.yaml', 'r') as f:
    log_cfg = yaml.safe_load(f.read())
    logging.config.dictConfig(log_cfg)  

logger = logging.getLogger(__name__)
logger.setLevel(logging.INFO)

logger.info("no-console. Should not be in console, but be in test.log!")
logger.info('This is an info message')
logger.error('This is an error message')

控制台中的预期输出没有“no-console”消息：

   2020-04-27 18:05:26,936 __main__: This is an info message 
   2020-04-27 18:05:26,936 __main__: This is an error message

但看起来像类：noConsoleFilter甚至没有被考虑，因为 print 语句也不起作用。

我哪里错了？我该如何修复它？

语法有点奇怪，但它在日志记录文档中进行了描述，位于用户定义的对象 https://docs.python.org/3/library/logging.config.html#logging-config-dict-userdef，你必须使用密钥(), not class。就像这样：

filters:
  noConsoleFilter:
    (): noConsoleFilter

接下来，您需要为类指定一个限定名称。如果您直接运行脚本，而不是作为模块，您可以在下面引用它__main__:

filters:
  noConsoleFilter:
    (): __main__.noConsoleFilter

我还建议使用 PEP 8类名的 CapWords 约定 https://www.python.org/dev/peps/pep-0008/#class-names。这是一个稍微整理过的、完全独立的示例：

# logging.yml
version: 1

formatters:
  simple_formatter:
    format: "%(asctime)s %(name)s: %(message)s"
  extended_formatter:
    format: "%(asctime)s %(name)s %(levelname)s: %(message)s"

filters:
  no_console_filter:
    (): __main__.NoConsoleFilter

handlers:
  console_handler:
    class: logging.StreamHandler
    level: INFO
    formatter: simple_formatter
    filters: [no_console_filter]

  file_handler:
    class: logging.FileHandler
    level: INFO
    filename: test.log
    formatter: extended_formatter

root:
  handlers: [console_handler, file_handler]
  propagate: true

# script.py
import logging.config
import yaml

class NoConsoleFilter(logging.Filter):
    def filter(self, record):
        print('filtering!')
        return not (record.levelname == 'INFO') & ('no-console' in record.msg)

with open('logging.yml', 'r') as f:
    log_cfg = yaml.safe_load(f.read())
    logging.config.dictConfig(log_cfg)

logger = logging.getLogger(__name__)
logger.setLevel(logging.INFO)

logger.info('no-console. Should not be in console, but be in test.log!')
logger.info('This is an info message')
logger.error('This is an error message')