js+输出日志文件

const fs = require('fs');
const path = require('path');

// 定义日志级别
const LOG_LEVELS = {
    DEBUG: 'DEBUG',
    INFO: 'INFO',
    WARN: 'WARN',
    ERROR: 'ERROR'
};

// 当前日志级别
let currentLogLevel = LOG_LEVELS.INFO;

// 日志文件路径
const logFilePath = path.join(__dirname, 'app.log');

// 写入日志函数
function writeLog(level, message) {
    if (LOG_LEVELS[level] && LOG_LEVELS[level] >= currentLogLevel) {
        const logEntry = `${new Date().toISOString()} [${level}] ${message}\n`;
        fs.appendFile(logFilePath, logEntry, (err) => {
            if (err) console.error('Logging failed:', err);
        });
    }
}

// 使用示例
writeLog(LOG_LEVELS.DEBUG, 'This is a debug message'); // 不会记录，因为当前日志级别是INFO
writeLog(LOG_LEVELS.INFO, 'This is an info message'); // 会记录
writeLog(LOG_LEVELS.WARN, 'This is a warning message'); // 会记录
writeLog(LOG_LEVELS.ERROR, 'This is an error message'); // 会记录

const winston = require('winston');
require('winston-daily-rotate-file');

const transport = new winston.transports.DailyRotateFile({
    filename: 'logs/app-%DATE%.log',
    datePattern: 'YYYY-MM-DD',
    zippedArchive: true,
    maxSize: '20m',
    maxFiles: '14d'
});

const logger = winston.createLogger({
    transports: [
        transport
    ]
});

logger.info('This is an info message with winston');
logger.error('This is an error message with winston');