最简单的用法：
import logging logging.debug("logging debug") logging.info("logging info") logging.warning("user [qianduoduo] attempted wrong password more than 3 times") logging.error("logging error") logging.critical("logging critical") #输出 WARNING:root:user [qianduoduo] attempted wrong password more than 3 times ERROR:root:logging error CRITICAL:root:logging critical #root 就是默认的用户名
重点：为什么上面debug和info没有输出，那是因为一个模块默认的日志级别是warning，比他级别低的就不会输出
把日志写到文件系统里
import logging
logging.basicConfig(filename=‘duoduo.log‘,
level=logging.DEBUG,
format=‘%(asctime)s %(message)s‘,#asctime字符串形式的当前时间，message用户输出的消息
datefmt=‘%Y-%m-%d %I:%M:%S %p ‘)
logging.debug("logging debug")
logging.info("logging info")
logging.warning("user [qianduoduo] attempted wrong password more than 3 times")
logging.error("logging error")
logging.critical("logging critical")
#输出到文件‘duoduo.log’
2018-01-27 07:33:30 PM logging debug
2018-01-27 07:33:30 PM logging info
2018-01-27 07:33:30 PM user [qianduoduo] attempted wrong password more than 3 times
2018-01-27 07:33:30 PM logging error
2018-01-27 07:33:30 PM logging critical
format的日志格式
|
|
Logger的名字 |
|
%(levelno)s |
数字形式的日志级别 |
|
%(levelname)s |
文本形式的日志级别 |
|
%(pathname)s |
调用日志输出函数的模块的完整路径名，可能没有 |
|
%(filename)s |
调用日志输出函数的模块的文件名 |
|
%(module)s |
调用日志输出函数的模块名 |
|
%(funcName)s |
调用日志输出函数的函数名 |
|
%(lineno)d |
调用日志输出函数的语句所在的代码行 |
|
%(created)f |
当前时间，用UNIX标准的表示时间的浮 点数表示 |
|
%(relativeCreated)d |
输出日志信息时的，自Logger创建以 来的毫秒数 |
|
%(asctime)s |
字符串形式的当前时间。默认格式是 “2003-07-08 16:49:45,896”。逗号后面的是毫秒 |
|
%(thread)d |
线程ID。可能没有 |
|
%(threadName)s |
线程名。可能没有 |
|
%(process)d |
进程ID。可能没有 |
|
%(message)s |
用户输出的消息 |
通过配置文件配置log
{
"version":1,
"disable_existing_loggers":false,
"formatters":{
"simple":{
"format":"%(asctime)s - %(name)s - %(levelname)s - %(message)s"
}
},
"handlers":{
"console":{
"class":"logging.StreamHandler",
"level":"DEBUG",
"formatter":"simple",
"stream":"ext://sys.stdout"
},
"info_file_handler":{
"class":"logging.handlers.RotatingFileHandler",
"level":"INFO",
"formatter":"simple",
"filename":"logs/info.log",
"maxBytes":10485760,
"backupCount":20,
"encoding":"utf8"
},
"error_file_handler":{
"class":"logging.handlers.RotatingFileHandler",
"level":"ERROR",
"formatter":"simple",
"filename":"logs/errors.log",
"maxBytes":10485760,
"backupCount":20,
"encoding":"utf8"
}
},
"loggers":{
"my_module":{
"level":"DEBUG",
"handlers":["info_file_handler"],
"propagate":"no"
}
},
"root":{
"level":"INFO",
"handlers":["console","info_file_handler","error_file_handler"]
}
}
在程序中引用
import json
import logging
import logging.config
import os
def setup_logging(default_path="logging.json", default_level=logging.INFO, env_key="LOG_CFG"):
path = default_path
value = os.getenv(env_key, None)
if value:
path = value
if os.path.exists(path):
with open(path, "r") as f:
config = json.load(f)
logging.config.dictConfig(config)
else:
logging.basicConfig(level=default_level)
if __name__ == "__main__":
setup_logging(default_path="logging.json")
