RocketChat/Rocket.Chat

import type { ServerResponse } from 'http';

import type { IncomingMessage } from 'connect';
import { WebApp } from 'meteor/webapp';
import { match } from 'path-to-regexp';

const matchRoute = match<{ lng: string }>('/:lng.json', { decode: decodeURIComponent });

const i18nHandler = async function (req: IncomingMessage, res: ServerResponse) {
    const url = new URL(req.url ?? '/', `https://${req.headers.host}`);
    const match = matchRoute(url.pathname);

    if (match === false) {
        res.writeHead(400);
        res.end();
        return;
    }

    const { lng } = match.params;

    try {
        const data = await Assets.getTextAsync(`i18n/${lng}.i18n.json`);
        if (!data) {
            throw new Error();
        }

        res.setHeader('Content-Type', 'application/json');
        res.setHeader('Content-Length', data.length);
        res.writeHead(200);
        res.end(data);
    } catch (e) {
        res.writeHead(400);
        res.end();
    }
};

WebApp.connectHandlers.use('/i18n/', i18nHandler);