Duyet MCP Server

/** * Debug logging utility for MCP server * * Provides structured logging with levels and categories. * All debug logs can be enabled/disabled via environment. */ export type LogLevel = "debug" | "info" | "warn" | "error"; export type LogCategory = | "init" | "request" | "tool" | "resource" | "cache" | "fetch" | "database" | "auth"; interface LogEntry { timestamp: string; level: LogLevel; category: LogCategory; message: string; data?: Record<string, unknown>; } /** * Logger class for structured debug logging */ class Logger { private enabled = true; private minLevel: LogLevel = "debug"; private levelPriority: Record<LogLevel, number> = { debug: 0, info: 1, warn: 2, error: 3, }; /** * Check if logging should occur for given level */ private shouldLog(level: LogLevel): boolean { if (!this.enabled) return false; return this.levelPriority[level] >= this.levelPriority[this.minLevel]; } /** * Format log entry for output */ private formatLog(entry: LogEntry): string { const dataStr = entry.data ? ` ${JSON.stringify(entry.data)}` : ""; return `[${entry.timestamp}] [${entry.level.toUpperCase()}] [${entry.category}] ${entry.message}${dataStr}`; } /** * Core logging method */ private log( level: LogLevel, category: LogCategory, message: string, data?: Record<string, unknown>, ): void { if (!this.shouldLog(level)) return; const entry: LogEntry = { timestamp: new Date().toISOString(), level, category, message, data, }; const formatted = this.formatLog(entry); switch (level) { case "error": console.error(formatted); break; case "warn": console.warn(formatted); break; default: console.log(formatted); } } // Convenience methods for different levels debug( category: LogCategory, message: string, data?: Record<string, unknown>, ): void { this.log("debug", category, message, data); } info( category: LogCategory, message: string, data?: Record<string, unknown>, ): void { this.log("info", category, message, data); } warn( category: LogCategory, message: string, data?: Record<string, unknown>, ): void { this.log("warn", category, message, data); } error( category: LogCategory, message: string, data?: Record<string, unknown>, ): void { this.log("error", category, message, data); } // Category-specific convenience methods tool(toolName: string, action: string, data?: Record<string, unknown>): void { this.debug("tool", `${toolName}: ${action}`, data); } resource( resourceName: string, action: string, data?: Record<string, unknown>, ): void { this.debug("resource", `${resourceName}: ${action}`, data); } cacheHit(key: string, config?: string): void { this.debug("cache", `HIT: ${key}`, config ? { config } : undefined); } cacheMiss(key: string, config?: string): void { this.debug("cache", `MISS: ${key}`, config ? { config } : undefined); } cacheSet(key: string, ttl: number): void { this.debug("cache", `SET: ${key}`, { ttl }); } fetch(url: string, status?: number, duration?: number): void { this.debug("fetch", `${url}`, { status, duration }); } request(method: string, path: string, data?: Record<string, unknown>): void { this.debug("request", `${method} ${path}`, data); } /** * Set minimum log level */ setLevel(level: LogLevel): void { this.minLevel = level; } /** * Enable/disable logging */ setEnabled(enabled: boolean): void { this.enabled = enabled; } } // Export singleton instance export const logger = new Logger(); // Export for direct import export default logger;