feat(server-side): custom default config path (#2084)

README.md

@@ -329,6 +329,34 @@ For example, if you want to use `{` and `}` the config would look like this:
 }
 ```
 
+#### Custom `next-i18next.config.js` path
+
+If you want to change the default config path, you can set the environment variable `I18NEXT_DEFAULT_CONFIG_PATH`.
+
+For example, inside the `.env` file you can set a static path:
+```
+I18NEXT_DEFAULT_CONFIG_PATH=/path/to/project/apps/my-app/next-i18next.config.js
+```
+
+Or you can use a trick for dynamic path and set the following inside `next.config.js`:
+
+```js
+process.env.I18NEXT_DEFAULT_CONFIG_PATH = `${__dirname}/next-i18next.config.js`;
+
+// ... Some other imports
+
+const { i18n } = require('./next-i18next.config');
+
+// ... Some other code
+
+module.exports = {
+  i18n,
+  ...
+};
+```
+
+This means that the i18n configuration file will be in the same directory as `next.config.js` and it doesn't matter where your current working directory is. This helps for example for `nx` when you have monorepo and start your application from project root but the application is in `apps/{appName}`.
+
 ## Notes
 
 ### Vercel and Netlify

src/serverSideTranslations.ts

@@ -9,7 +9,7 @@ import { globalI18n } from './appWithTranslation'
 import { UserConfig, SSRConfig } from './types'
 import { getFallbackForLng, unique } from './utils'
 
-const DEFAULT_CONFIG_PATH = './next-i18next.config.js'
+const { I18NEXT_DEFAULT_CONFIG_PATH: DEFAULT_CONFIG_PATH = './next-i18next.config.js' } = process.env
 
 export const serverSideTranslations = async (
   initialLocale: string,