MCP Server Demo

import { Config, ConfigSchema, defaultConfig } from './database.js'; import path from 'path'; import fs from 'fs'; import { fileURLToPath } from 'url'; import dotenv from 'dotenv'; export class ConfigManager { private config!: Config; private configPath: string; constructor() { const env = process.env.NODE_ENV || 'development'; const __dirname = path.dirname(fileURLToPath(import.meta.url)); // 当从 dist/src 运行时，需要向上两级到达包根目录 const packageRoot = path.resolve(__dirname, '../..'); // 加载环境变量文件 this.loadEnvironmentVariables(packageRoot, env); this.configPath = path.resolve(packageRoot, `config/database-${env}.json`); this.loadConfig(); } private loadEnvironmentVariables(packageRoot: string, env: string): void { const envPath = path.resolve(packageRoot, `.env.${env}`); // 优先加载通用 .env 文件 const commonEnvPath = path.resolve(packageRoot, '.env'); if (fs.existsSync(commonEnvPath)) { dotenv.config({ path: commonEnvPath }); console.error(`已加载通用环境变量文件: ${commonEnvPath}`); } // 再加载特定环境的 .env 文件，会覆盖通用配置 if (fs.existsSync(envPath)) { dotenv.config({ path: envPath }); console.error(`已加载环境变量文件: ${envPath}`); } else { console.warn(`环境变量文件不存在: ${envPath}`); console.warn(`请复制 env-templates/${env}.env.template 为 .env.${env} 并配置相应的值`); } } loadConfig(): void { try { console.error('正在读取配置文件从:', this.configPath); if (fs.existsSync(this.configPath)) { const configContent = fs.readFileSync(this.configPath, 'utf-8'); console.error('配置文件内容前50个字符:', configContent.substring(0, 50)); // 解析环境变量占位符 const resolvedContent = this.resolveEnvironmentVariables(configContent); const configData = JSON.parse(resolvedContent); this.config = ConfigSchema.parse(configData); console.error('配置加载成功'); } else { console.error('配置文件不存在:', this.configPath); this.config = defaultConfig; this.saveConfig(); } // 从环境变量覆盖配置 this.overrideFromEnv(); } catch (error) { console.error('加载配置失败，使用默认配置：', error); this.config = defaultConfig; } } private resolveEnvironmentVariables(content: string): string { // 解析 ${VAR} 和 ${VAR:-default} 格式的环境变量占位符 return content.replace(/\$\{([^}]+)\}/g, (match, varExpression) => { const [varName, defaultValue] = varExpression.split(':-'); const envValue = process.env[varName.trim()]; if (envValue !== undefined) { return envValue; } else if (defaultValue !== undefined) { return defaultValue.trim(); } else { // 如果环境变量不存在且没有默认值，保持原样或返回空字符串 console.warn(`环境变量 ${varName} 未设置且无默认值`); return ''; } }); } private overrideFromEnv() { // 覆盖通用环境配置 if (process.env.OPENAI_API_KEY) { this.config.environment.openaiApiKey = process.env.OPENAI_API_KEY; } if (process.env.DEFAULT_DATABASE) { this.config.environment.defaultDatabase = process.env.DEFAULT_DATABASE; } if (process.env.MAX_QUERY_RESULTS) { this.config.environment.maxQueryResults = parseInt(process.env.MAX_QUERY_RESULTS); } if (process.env.ENABLE_CACHE) { this.config.environment.enableCache = process.env.ENABLE_CACHE === 'true'; } if (process.env.LOG_LEVEL) { const logLevel = process.env.LOG_LEVEL as 'debug' | 'info' | 'warn' | 'error'; if (['debug', 'info', 'warn', 'error'].includes(logLevel)) { this.config.environment.logLevel = logLevel; } } } private saveConfig() { try { const configDir = path.dirname(this.configPath); if (!fs.existsSync(configDir)) { fs.mkdirSync(configDir, { recursive: true }); } fs.writeFileSync(this.configPath, JSON.stringify(this.config, null, 2)); } catch (error) { console.error('Error saving config:', error); } } public getConfig(): Config { return this.config; } public getDatabaseConfig(id: string) { return this.config.databases.find((db: any) => db.id === id); } public getDefaultDatabaseConfig() { const defaultId = this.config.environment.defaultDatabase; return defaultId ? this.getDatabaseConfig(defaultId) : this.config.databases[0]; } public getAllDatabases() { return this.config.databases; } }