Encountering Error: ENOENT: no such file or directory, scandir 'XXX' occasionally

[yuuk]

🐛 Bug Report

Our project is undergoing pressure testing in docker container by JMeter, when the concurrent count is high, the following error will occur, But the directory is actually exist.

2023-12-25 07:47 +00:00: Error: ENOENT: no such file or directory, scandir '/app/packages/eshop/public/locales/cn'
    at Object.readdirSync (node:fs:1405:3)
    at getLocaleNamespaces (/app/node_modules/next-i18next/dist/commonjs/config/createConfig.js:214:16)
    at /app/node_modules/next-i18next/dist/commonjs/config/createConfig.js:231:20
    at Array.map (<anonymous>)
    at getNamespaces (/app/node_modules/next-i18next/dist/commonjs/config/createConfig.js:230:44)
    at createConfig (/app/node_modules/next-i18next/dist/commonjs/config/createConfig.js:271:29)
    at _callee$ (/app/node_modules/next-i18next/dist/commonjs/serverSideTranslations.js:201:53)
    at tryCatch (/app/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:44:17)
    at Generator.<anonymous> (/app/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:125:22)
    at Generator.next (/app/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:69:21) {
  errno: -2,
  syscall: 'scandir',
  path: '/app/packages/eshop/public/locales/cn'
}

2023-12-25 07:46 +00:00: Error: ENOENT: no such file or directory, scandir '/app/packages/eshop/public/locales/cn'
    at Object.readdirSync (node:fs:1405:3)
    at getLocaleNamespaces (/app/node_modules/next-i18next/dist/commonjs/serverSideTranslations.js:241:37)
    at /app/node_modules/next-i18next/dist/commonjs/serverSideTranslations.js:247:22
    at Array.map (<anonymous>)
    at _callee$ (/app/node_modules/next-i18next/dist/commonjs/serverSideTranslations.js:246:64)
    at tryCatch (/app/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:44:17)
    at Generator.<anonymous> (/app/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:125:22)
    at Generator.next (/app/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:69:21)
    at asyncGeneratorStep (/app/node_modules/@babel/runtime/helpers/asyncToGenerator.js:3:24)
    at _next (/app/node_modules/@babel/runtime/helpers/asyncToGenerator.js:22:9) {
  errno: -2,
  syscall: 'scandir',
  path: '/app/packages/eshop/public/locales/cn'
}

Here is the PT report could show the relationship between concurrent count and error count. The more concurrent count, the more error count.

I tried to invoke a large number of fs.readdirSync to read the directory, it didn't occur the error.

Maybe this is not next-i18next's problem, but I have no clue...

To Reproduce

next-i18next.config.js

const path = require('path');

module.exports = {
    i18n: {
        defaultLocale: 'none',
        locales: ['en', 'cn', 'tc', 'jp', 'it', 'fr', 'kr', 'none'],
    },
    localeExtension: 'json',
    defaultNS: 'common',
    localePath: path.resolve(__dirname, 'public/locales'),
    reloadOnPrerender: process.env.NODE_ENV === 'development',
};

PM2 config

const path = require('path');

module.exports = {
    apps: [
        {
            ...
            script: path.resolve(__dirname, './start.js'),
            cwd: path.resolve(__dirname),
            watch: false,
            watch_delay: 1000,
            ignore_watch: ['node_modules'],
            instances: 'max',
            exec_mode: 'cluster',
            ...
        },
    ],
};

It's not easy to reproduce, unless use high concurrent request.

Expected behavior

Do not report errors

Your Environment

• runtime version: node v16.16.0, next v12.2.0
• i18next version: 21.10.0
• os: Linux
• next-i18next: 11.3.0