Node.js使用mime/file-type模块触发ERR_REQUIRE_ESM错误求助

问题重现 #

在TypeScript项目中尝试用mime模块识别文件类型，编写代码如下：

import mime from 'mime';
// import { mime } from 'mime'; // 也尝试过该写法

const determineFileType = async (filePath) => {
  const type = mime.getType(filePath);
  if (type) {
    logger.info(`File type is: ${type.mime} and the extension is: ${type.ext}`);
  } else {
    logger.info(`Could not determine the file type for ${filePath}`);
  }
  return type;
};

执行后触发错误：

2024-Feb-18 09:11:29:1129 +0ms ip-172-31-47-89 pid:586768 error: uncaughtException: require() of ES Module /home/ubuntu/my-app/node_modules/mime/dist/src/index.js from /home/ubuntu/my-app/src/utils/decompress.ts not supported.
Instead change the require of index.js in /home/ubuntu/my-app/src/utils/decompress.ts to a dynamic import() which is available in all CommonJS modules.
Error [ERR_REQUIRE_ESM]: require() of ES Module /home/ubuntu/my-app/node_modules/mime/dist/src/index.js from /home/ubuntu/my-app/src/utils/decompress.ts not supported.
Instead change the require of index.js in /home/ubuntu/my-app/src/utils/decompress.ts to a dynamic import() which is available in all CommonJS modules.
    at require.extensions.<computed> [as .js] (/home/ubuntu/my-app/node_modules/ts-node/dist/index.js:851:20)
    at Object.<anonymous> (/home/ubuntu/my-app/src/utils/decompress.ts:19:32)
    at m._compile (/home/ubuntu/my-app/node_modules/ts-node/dist/index.js:857:29)
(node:586768) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
(Use `node --trace-deprecation ...` to show where the warning was created)
[nodemon] app crashed - waiting for file changes before starting...

随后改用file-type模块：

import { fileTypeFromFile } from 'file-type';

...
const type = await fileTypeFromFile(filePath);
...

触发类似错误：

2024-Feb-18 09:14:12:1412 +0ms ip-172-31-47-89 pid:587367 error: uncaughtException: require() of ES Module /home/ubuntu/my-app/node_modules/file-type/index.js from /home/ubuntu/my-app/src/utils/decompress.ts not supported.
Instead change the require of index.js in /home/ubuntu/my-app/src/utils/decompress.ts to a dynamic import() which is available in all CommonJS modules.
Error [ERR_REQUIRE_ESM]: require() of ES Module /home/ubuntu/my-app/node_modules/file-type/index.js from /home/ubuntu/my-app/src/utils/decompress.ts not supported.
Instead change the require of index.js in /home/ubuntu/my-app/src/utils/decompress.ts to a dynamic import() which is available in all CommonJS modules.
    at require.extensions.<computed> [as .js] (/home/ubuntu/my-app/node_modules/ts-node/dist/index.js:851:20)
    at Object.<anonymous> (/home/ubuntu/my-app/src/utils/decompress.ts:19:21)
    at m._compile (/home/ubuntu/my-app/node_modules/ts-node/dist/index.js:857:29)
(node:587367) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
(Use `node --trace-deprecation ...` to show where the warning was created)

错误核心原因 #

这个错误的本质是模块系统不兼容：

1. mime和file-type的最新版本都是纯ES模块（ESM），这类模块在自身的package.json中会声明"type": "module"，Node.js会强制以ESM规则加载它们。
2. 你的TypeScript项目当前是以**CommonJS（CJS）**模式运行的：
   • 要么你的项目package.json中没有设置"type": "module"，Node.js默认将编译后的.js文件当作CJS处理；
   • 要么你的tsconfig.json中compilerOptions.module设置为CommonJS（默认值），导致ts-node将TypeScript代码编译成CJS格式的代码。
3. Node.js禁止在CJS模块中用require()加载ESM模块，而ts-node编译后的CJS代码尝试用require()加载这两个ESM依赖，直接触发了ERR_REQUIRE_ESM错误。

内容的提问来源于stack exchange，提问作者Kid_Learning_C