leshan-mcp-server/src/utils/logger.js

A standards-compliant MCP server for Leshan LwM2M, exposing Leshan as Model Context Protocol tools.

import { createWriteStream } from 'fs';
import { join } from 'path';

class Logger {
  constructor() {
    this.logStream = createWriteStream(join(process.cwd(), 'logs', 'mcp-server.log'), { flags: 'a' });
  }

  log(level, message, meta = {}) {
    const timestamp = new Date().toISOString();
    const logEntry = {
      timestamp,
      level,
      message,
      ...meta
    };
    
    // Log to stderr for MCP (not stdout which is reserved for MCP protocol)
    console.error(`[${timestamp}] ${level.toUpperCase()}: ${message}`);
    
    // Also log to file
    this.logStream.write(JSON.stringify(logEntry) + '\n');
  }

  info(message, meta) { this.log('info', message, meta); }
  warn(message, meta) { this.log('warn', message, meta); }
  error(message, meta) { this.log('error', message, meta); }
  debug(message, meta) { this.log('debug', message, meta); }
}

export default new Logger();