rt-sim-training-client/src/utils/lang.js

import Cookies from 'js-cookie';

const I18N_LANG = 'user_lang';
export default {
    setLang(lang) {
        Cookies.set(I18N_LANG, lang);
        window.location.reload();
    },
    getLang(defaultLang) {
        const localLang = Cookies.get(I18N_LANG);

        if (localLang == null) {
            return defaultLang;
        } else {
            return localLang;
        }
    }
};