导出的envKeys变量仅在checkEnv.ts中未定义的问题求助

报错信息：

return botConfig_1.envKeys.reduce((acc, current) => {

TypeError: Cannot read properties of undefined (reading 'reduce')

项目配置 #

• 编译目标：ES2022
• 模块规范：CommonJS
• 模块解析方式：Node
• 启用useStrict

相关文件代码 #

checkEnv.ts #

import { ENV, Config } from "../configs/types";
import { envKeys } from "../configs/botConfig";
import { config } from "dotenv";
config();

//const envKeys = ["TOKEN", "ID", "PREFIX", "MONGO_URI"] as const;

/**
 * This function gets the env and returns the specific things
 * @returns 
 */
export function getEnvConfig(): ENV {

    return envKeys.reduce((acc, current) => {
        acc[current] = process.env[current]
        return acc
    }, {} as ENV)
};
/**
 * This function returns every .env type that was specified. It gives it a proper Type and so much more.
 * @param config   The config that should check it trough
 * @returns 
 */
export function getSanitzedConfig(config: ENV): Config {
    for (const [key, value] of Object.entries(config)) {
        if (value === undefined) {
            throw new Error(`Missing key ${key} in .env`)
        }
    };
    
    return config as Config;
};

botConfig.ts #

import { botConfigType } from "./types";
import { getEnvConfig, getSanitzedConfig } from "../utils/checkEnv";

const { TOKEN, ID, PREFIX, MONGO_URI } = getSanitzedConfig(getEnvConfig());

const data: botConfigType = {
    token: TOKEN,
    ID: ID,
    prefix: PREFIX,
    owners: [""],
    mongo_uri: MONGO_URI,

};

// Export the envKeys for the checkEnv file
export const envKeys = ["TOKEN", "ID", "PREFIX", "MONGO_URI"] as const;

// Export the botConfig
export default data;

types.ts #

import { envKeys } from "./botConfig";

export type botConfigType = {
    token: string;
    ID: string;
    prefix: string;
    owners: string[];
    mongo_uri: string;
};

export type EnvKeys = typeof envKeys[number];
export type ENV = { [key in EnvKeys]?: string | undefined };
export type Config = { [key in EnvKeys]: string };

已尝试的无效方法 #

• 检查循环依赖（未发现）
• 删除dist文件夹重新编译
• 将envKeys移至checkEnv.ts内（此方法有效但不符合需求）
• 检查编译后的文件（未发现异常）

解决方案 #

核心问题是循环依赖导致的运行时执行顺序错误：botConfig.ts先调用getEnvConfig()（依赖envKeys），但envKeys定义在文件末尾，此时还未初始化，所以checkEnv.ts拿到的是undefined。TypeScript类型导入是静态的，不会影响运行时，因此types.ts能正常使用envKeys。

方法1：拆分envKeys到独立模块 #

创建configs/envKeys.ts：

export const envKeys = ["TOKEN", "ID", "PREFIX", "MONGO_URI"] as const;

然后在三个文件中统一导入这个模块：

• checkEnv.ts：import { envKeys } from "../configs/envKeys";
• botConfig.ts：import { envKeys } from "./envKeys";
• types.ts：import { envKeys } from "./envKeys";
  彻底消除循环依赖，避免执行顺序问题。

方法2：调整botConfig.ts代码顺序 #

将envKeys的定义移到文件最顶部，确保调用getEnvConfig()前变量已初始化：

import { botConfigType } from "./types";
import { getEnvConfig, getSanitzedConfig } from "../utils/checkEnv";

// 先定义envKeys
export const envKeys = ["TOKEN", "ID", "PREFIX", "MONGO_URI"] as const;

// 再调用依赖函数
const { TOKEN, ID, PREFIX, MONGO_URI } = getSanitzedConfig(getEnvConfig());

const data: botConfigType = {
    token: TOKEN,
    ID: ID,
    prefix: PREFIX,
    owners: [""],
    mongo_uri: MONGO_URI,
};

export default data;

内容的提问来源于stack exchange，提问作者Joniii11