/**
* 日志级别枚举
*/
export enum LogLevel {
DEBUG = 0,
INFO = 1,
WARN = 2,
ERROR = 3,
OFF = 4,
}
/**
* 日志级别字符串映射
*/
const LOG_LEVEL_NAMES: Record<LogLevel, string> = {
[LogLevel.DEBUG]: "DEBUG",
[LogLevel.INFO]: "INFO",
[LogLevel.WARN]: "WARN",
[LogLevel.ERROR]: "ERROR",
[LogLevel.OFF]: "OFF",
};
/**
* 日志级别颜色代码 (用于终端输出)
*/
const LOG_LEVEL_COLORS: Record<LogLevel, string> = {
[LogLevel.DEBUG]: "\x1b[36m", // 青色
[LogLevel.INFO]: "\x1b[32m", // 绿色
[LogLevel.WARN]: "\x1b[33m", // 黄色
[LogLevel.ERROR]: "\x1b[31m", // 红色
[LogLevel.OFF]: "\x1b[0m", // 重置
};
const RESET_COLOR = "\x1b[0m";
/**
* Logger 类 - 提供结构化日志功能
*/
class Logger {
private level: LogLevel;
private enableColors: boolean;
constructor() {
// 从环境变量读取日志级别，默认为 INFO
this.level = this.parseLogLevel(process.env.LOG_LEVEL || "INFO");
// 从环境变量读取是否启用颜色，默认启用
this.enableColors = process.env.LOG_COLORS !== "false";
}
/**
* 解析日志级别字符串
*/
private parseLogLevel(level: string): LogLevel {
const upperLevel = level.toUpperCase();
switch (upperLevel) {
case "DEBUG":
return LogLevel.DEBUG;
case "INFO":
return LogLevel.INFO;
case "WARN":
return LogLevel.WARN;
case "ERROR":
return LogLevel.ERROR;
case "OFF":
return LogLevel.OFF;
default:
return LogLevel.INFO;
}
}
/**
* 格式化时间戳
*/
private formatTimestamp(): string {
const now = new Date();
return now.toISOString();
}
/**
* 格式化日志消息
*/
private formatMessage(level: LogLevel, message: string, data?: any): string {
const timestamp = this.formatTimestamp();
const levelName = LOG_LEVEL_NAMES[level];
const color = this.enableColors ? LOG_LEVEL_COLORS[level] : "";
const reset = this.enableColors ? RESET_COLOR : "";
let formattedMessage = `${timestamp} ${color}[${levelName}]${reset} ${message}`;
// 如果有额外数据，添加到消息中
if (data !== undefined) {
if (typeof data === "object") {
formattedMessage += ` ${JSON.stringify(data)}`;
} else {
formattedMessage += ` ${data}`;
}
}
return formattedMessage;
}
/**
* 通用日志输出方法
*/
private log(level: LogLevel, message: string, data?: any): void {
if (level < this.level) {
return; // 低于当前日志级别，不输出
}
const formattedMessage = this.formatMessage(level, message, data);
// 根据日志级别选择输出流
if (level >= LogLevel.WARN) {
console.error(formattedMessage);
} else {
console.error(formattedMessage); // MCP 服务器统一使用 stderr
}
}
/**
* DEBUG 级别日志 - 详细的调试信息
*/
debug(message: string, data?: any): void {
this.log(LogLevel.DEBUG, message, data);
}
/**
* INFO 级别日志 - 一般信息
*/
info(message: string, data?: any): void {
this.log(LogLevel.INFO, message, data);
}
/**
* WARN 级别日志 - 警告信息
*/
warn(message: string, data?: any): void {
this.log(LogLevel.WARN, message, data);
}
/**
* ERROR 级别日志 - 错误信息
*/
error(message: string, data?: any): void {
this.log(LogLevel.ERROR, message, data);
}
/**
* 设置日志级别
*/
setLevel(level: LogLevel): void {
this.level = level;
}
/**
* 获取当前日志级别
*/
getLevel(): LogLevel {
return this.level;
}
/**
* 启用/禁用颜色
*/
setColors(enabled: boolean): void {
this.enableColors = enabled;
}
}
// 导出单例
export const logger = new Logger();
