How to get translates from json file ?

[golubvladimir]

My config

i18next
  .use(i18nextMiddleware.LanguageDetector)
  .use(FilesystemBackend)
  .init({
    preload: ["en", "de"],
    detection: {
      order: ['path'],
      lookupPath: 'lng',
      caches: false
    },
    backend: {
      loadPath: '/lang/json/{{lng}}.json',
      jsonIndent: 2,
    }
  });

app.use(
  i18nextMiddleware.handle(i18next, {
    removeLngFromUrl: false
  })
);

app.get('/:lng/test-lang', (req, res) => {
  console.log(req);
  console.log(req.language);
  res.json({status: 'ok'});
});

How to get translates from json file ? What is req option ? How does preload option work ?

[golubvladimir]

It does not work

app.get('/:lng/test-lang', (req, res) => {
  console.log(req);
  console.log(req.language);
  console.log(i18next.t('test'));
});

[golubvladimir]

GET

http://localhost:3001/ru/test-lang

console.log(i18next.language);
undefined

[golubvladimir]

I fix my config

i18next
  .use(i18nextMiddleware.LanguageDetector)
  .use(FilesystemBackend)
  .init({
    debug: true,
    fallbackLng: ['en'],
    preload: ["en", "ru"],
    detection: {
      order: ['path'],
      lookupPath: 'lng',
      caches: false
    },
    backend: {
      loadPath: 'lang/json/{{lng}}.json',
      jsonIndent: 2,
    }
  });

app.use(
  i18nextMiddleware.handle(i18next, {
    removeLngFromUrl: false
  })
);

app.get('/:lng/test-lang', (req, res) => {
  console.log(i18next.language);
  console.log(i18next.t('test'));
});

For start, I have messages:

i18next::backendConnector: loaded namespace translation for language en {
  test: 'Test',
...

i18next::backendConnector: loaded namespace translation for language ru {
  test: 'Тест',
...

i18next: languageChanged ru
undefined
i18next: hasLoadedNamespace: i18n.languages were undefined or empty undefined
i18next::translator: key "test" for namespace "translation" for languages "en" won't get resolved as namespace was not yet loaded This means something IS WRONG in your application setup. You access the t function before i18next.init
 / i18next.loadNamespace / i18next.changeLanguage was done. Wait for the callback or Promise to resolve before accessing it!!!
Test

How to fix it ?

[golubvladimir]

It works with warnings.

console.log(req.t('test'));

i18next: languageChanged ru
i18next: hasLoadedNamespace: i18n.languages were undefined or empty undefined
i18next::translator: key "test" for namespace "translation" for languages "ru, en" won't get resolved as namespace was not yet loaded This means something IS WRONG in your application setup. You access the t function before i18next.
init / i18next.loadNamespace / i18next.changeLanguage was done. Wait for the callback or Promise to resolve before accessing it!!!
Тест

[jamuhl]

forget about:

app.get('/:lng/test-lang', (req, res) => {
  console.log(i18next.language);
  console.log(i18next.t('test'));
});

i18next.language is the main instance of i18next (singleton) which is useless in an async world were requests from different users with different languages are processed in an event loop...(using that miain instance would lead to mixed language output as request B overwrites language of request A)...

always access req.language and req.i18n and req.t