RocketChat/Rocket.Chat

import { Avatars, Rooms } from '@rocket.chat/models';
import { Cookies } from 'meteor/ostrio:cookies';

import { FileUpload } from '../../../app/file-upload/server';
import { roomCoordinator } from '../../lib/rooms/roomCoordinator';
import { renderSVGLetters, serveAvatar, wasFallbackModified, setCacheAndDispositionHeaders } from './utils';

const MAX_ROOM_SVG_AVATAR_SIZE = 1024;
const MIN_ROOM_SVG_AVATAR_SIZE = 16;

const cookie = new Cookies();
const getRoomAvatar = async (roomId) => {
    const room = await Rooms.findOneById(roomId, { projection: { t: 1, prid: 1, name: 1, fname: 1, federated: 1 } });
    if (!room) {
        return {};
    }

    const file = await Avatars.findOneByRoomId(room._id);

    // if it is a discussion that doesn't have it's own avatar, returns the parent's room avatar
    if (room.prid && !file) {
        return getRoomAvatar(room.prid);
    }

    return { room, file };
};

export const roomAvatar = async function (req, res /* , next*/) {
    const roomId = decodeURIComponent(req.url.substr(1).replace(/\?.*$/, ''));

    const { room, file } = await getRoomAvatar(roomId);
    if (!room) {
        res.writeHead(404);
        res.end();
        return;
    }

    const uid = req.headers.cookie && cookie.get('rc_uid', req.headers.cookie);

    const reqModifiedHeader = req.headers['if-modified-since'];
    if (file) {
        res.setHeader('Content-Security-Policy', "default-src 'none'");

        if (reqModifiedHeader && reqModifiedHeader === file.uploadedAt?.toUTCString()) {
            res.setHeader('Last-Modified', reqModifiedHeader);
            res.writeHead(304);
            res.end();
            return;
        }

        if (file.uploadedAt) {
            res.setHeader('Last-Modified', file.uploadedAt.toUTCString());
        }
        res.setHeader('Content-Type', file.type);
        res.setHeader('Content-Length', file.size);

        return FileUpload.get(file, req, res);
    }

    const roomName = await roomCoordinator.getRoomName(room.t, room, uid);

    setCacheAndDispositionHeaders(req, res);

    if (!wasFallbackModified(reqModifiedHeader, res)) {
        res.writeHead(304);
        res.end();
        return;
    }

    let avatarSize = req.query.size && parseInt(req.query.size);
    if (avatarSize) {
        avatarSize = Math.min(Math.max(avatarSize, MIN_ROOM_SVG_AVATAR_SIZE), MAX_ROOM_SVG_AVATAR_SIZE);
    }

    const svg = renderSVGLetters(roomName, avatarSize);

    return serveAvatar(svg, req.query.format, res);
};