Document

Tiny pub/sub by jQuery

(function($) {
var o         = $({});
$.subscribe   = o.on.bind(o);
$.unsubscribe = o.off.bind(o);
$.publish     = o.trigger.bind(o);
}(jQuery));

Improvement

Hold all the config information, e.g. db config, web-server config.

 import { WebServer } from '../etc/config'
 WebServer.PORT
 WebServer.getHTTPUrl()

So the web-server PORT, URL are united from same config file.

It is useful when align the

s, like menu, tabs, footer lists.

assets/style.scss

add media-object in About component,

Initialize socket.io in src/index.js as global variable, and in Chat.js, send message to server and ready to receive message from server.

add socket-login-users counters,

Redis Pub/Sub with socket.io, works fine. Can be multiple-subscribers for redis extensions.

update redis pub/sub

If there is a wrong router, e.g. /users-nyc/, it should return NotFound remindering.
If RESTFul APIs, e.g. /api/users/, it should return rest-json data from server.
generally react-router-dom-v4 Route return 3 props: { match, location, history }
match.url, match.params
location.pathname
currently work fine, as expected.
update auth login to mongo.

set-up /etc/footer-config, use it to loop footer flexbox instead of hard-code.
in Rooter->Footer, nest <Link/> inside <Button/>
Move socket ‘onlineLoggedIn’ from LoginApp.js to Header.js, when user login/logout, the header login number will update auto.
Use Header->state.totalLogins to display the total-login-number.