Python Web日志管理与监控实践指南

import logging

# 创建一个logger对象
logger = logging.getLogger('web_app_logger')

# 设置日志级别为DEBUG，意味着记录所有级别的日志
logger.setLevel(logging.DEBUG)

# 创建一个处理器，输出日志到控制台
console_handler = logging.StreamHandler()
console_handler.setLevel(logging.DEBUG)

# 定义日志格式
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
console_handler.setFormatter(formatter)

# 将处理器添加到logger中
logger.addHandler(console_handler)

# 日志记录示例
logger.debug('这是调试信息')
logger.info('这是普通信息')
logger.warning('这是警告信息')
logger.error('这是错误信息')
logger.critical('这是严重错误信息')

from flask import Flask
import logging

app = Flask(__name__)

# 设置Flask的日志级别为DEBUG
app.logger.setLevel(logging.DEBUG)

# 创建文件处理器，日志记录到文件
file_handler = logging.FileHandler('flask_app.log')
file_handler.setLevel(logging.DEBUG)

# 设置日志格式
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
file_handler.setFormatter(formatter)

# 将文件处理器添加到Flask的默认logger中
app.logger.addHandler(file_handler)

@app.route('/')
def index():
    app.logger.info('主页被访问')
    return 'Hello, Flask!'

if __name__ == '__main__':
    app.run()

# settings.py

LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'formatters': {
        'verbose': {
            'format': '{asctime} {levelname} {message}',
            'style': '{',
        },
    },
    'handlers': {
        'file': {
            'level': 'DEBUG',
            'class': 'logging.FileHandler',
            'filename': 'django_app.log',
            'formatter': 'verbose',
        },
    },
    'loggers': {
        'django': {
            'handlers': ['file'],
            'level': 'DEBUG',
            'propagate': True,
        },
    },
}

import logging
from logging.handlers import RotatingFileHandler

# 创建日志记录器
logger = logging.getLogger('rotating_logger')
logger.setLevel(logging.DEBUG)

# 设置日志处理器，文件最大5MB，最多保留3个旧文件
handler = RotatingFileHandler('app.log', maxBytes=5*1024*1024, backupCount=3)
handler.setLevel(logging.DEBUG)

# 设置日志格式
formatter = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
handler.setFormatter(formatter)

# 添加处理器到logger
logger.addHandler(handler)

# 日志记录示例
for i in range(10000):
    logger.info(f"记录日志条目 {i}")

from logging.handlers import TimedRotatingFileHandler

# 创建时间轮转的日志处理器，日志文件每天创建一次
time_handler = TimedRotatingFileHandler('timed_app.log', when='midnight', interval=1, backupCount=7)
time_handler.setLevel(logging.DEBUG)

# 设置日志格式
formatter = logging.Formatter('%(asctime)s - %(message)s')
time_handler.setFormatter(formatter)

logger.addHandler(time_handler)

# 日志记录示例
for i in range(10000):
    logger.debug(f"时间轮转日志记录 {i}")

# logstash配置示例 (logstash.conf)
input {
  file {
    path => "/path/to/your/logfile.log"
    start_position => "beginning"
  }
}

output {
  elasticsearch {
    hosts => ["localhost:9200"]
    index => "application-logs"
  }
}

# Fluentd配置示例
<source>
  @type tail
  path /var/log/app.log
  pos_file /var/log/td-agent/app.log.pos
  tag application.logs
  <parse>
    @type none
  </parse>
</source>

<match application.logs>
  @type forward
  <server>
    host 192.168.1.1
    port 24224
  </server>
</match>

# Prometheus 配置示例
scrape_configs:
  - job_name: 'flask_app'
    static_configs:
      - targets: ['localhost:5000']

import logging
from slack_sdk import WebClient

class SlackHandler(logging.Handler):
    def __init__(self, slack_token, channel):
        super().__init__()
        self.client = WebClient(token=slack_token)
        self.channel = channel

    def emit(self, record):
        log_entry = self.format(record)
        self.client.chat_postMessage(channel=self.channel, text=log_entry)

# 初始化Slack日志处理器
slack_handler = SlackHandler(slack_token='your-slack-token', channel='#logs')

# 将处理器添加到logger
logger.addHandler(slack_handler)

# 记录错误日志，将其发送到Slack
logger.error('这是一个发送到Slack的错误日志')