koa-i18next-middleware-fixed/src/index.js

An i18next middleware for koa2 framework with some fixes

'use strict';

import * as utils from './utils';
import LD from 'koa-i18next-detector';

export var LanguageDetector = LD;

export function getHandler(i18next, options = {}) {
    return async function(ctx, next) {
        let res = ctx.response;
        let req = ctx.request;
        let ignores =
            (options.ignoreRoutes instanceof Array && options.ignoreRoutes) ||
            [];
        if (ignores.some(ignore => ctx.path.includes(ignore))) {
            return await next();
        }
        let i18n = i18next.cloneInstance({ initImmediate: false });
        i18n.on('languageChanged', lng => {
            // Keep language in sync
            req.language = lng;
            req.locale = lng;
            req.lng = lng;
            req.languages = i18next.services.languageUtils.toResolveHierarchy(
                lng
            );
        });

        let lng = req.lng;
        if (!lng && i18next.services.languageDetector) {
            lng = i18next.services.languageDetector.detect(ctx);
        }

        // set request locale
        req.language = lng;
        req.locale = lng;
        req.lng = lng;
        req.languages = i18next.services.languageUtils.toResolveHierarchy(lng);

        // trigger sync to instance - might trigger async load!
        i18n.changeLanguage(lng || i18next.options.fallbackLng[0]);

        if (req.i18nextLookupName === 'path' && options.removeLngFromUrl) {
            req.url = utils.removeLngFromUrl(
                req.url,
                i18next.services.languageDetector.options.lookupFromPathIndex
            );
        }

        let t = i18n.t.bind(i18n);
        let exists = i18n.exists.bind(i18n);

        // assert for req
        req.i18n = i18n;
        req.t = t;

        // assert for res -> template
        let localsName = options.locals || 'locals';
        if (!res[localsName]) {
            res[localsName] = {};
        }

        res[localsName].t = t;
        res[localsName].exists = exists;
        res[localsName].i18n = i18n;
        res[localsName].language = lng;
        res[localsName].languageDir = i18next.dir(lng);

        if (i18next.services.languageDetector) {
            i18next.services.languageDetector.cacheUserLanguage(ctx, lng);
        }

        // load resources
        if (!req.lng) {
            await next();
        } else {
            await i18next.loadLanguages(req.lng);
            await next();
        }
    };
}

export default {
    getHandler
};