full-stack-bus

communicating ALL your applications with RabbitMQ, postal.js and

javascript

javier arias losada @javier_arilos

imagine...

imagine your app needs growing (*)

it’s easy if you try

(*) by growing I mean functionality and/or performance and/or scalability

message bus

A message bus enables separate applications to work together, but in a decoupled fashion [1].

[1] http://bit.ly/1GI9W3B

message what?

Message bus technologies have been used in backend for more than 20 years: IBM MQSeries in 1992 [2].

[2] http://bit.ly/1GIbV8f

did you say backend?

Nowadays we can use message bus in the browser with the help of libraries such as postal.js [3].

[3] http://bit.ly/1zozbq9

what’s full-stack-bus?

Yet Another Buzzword...

seriously, what’s full-stack-bus?

By uniting frontend and backend bus technologies we can create applications that work out together in a decoupled fashion.

frontend => frontend

frontend => backend

backend => frontend

backend => backend

… but I already do that!!!!

frontend => frontend: eventEmitters, listeners, global variables...

frontend => backend: HTTP, Websockets...

backend => frontend: Websockets, Long-polling...

backend => backend : HTTP, sockets, shared Db...

Some of this are good mechanisms.

...others are just antipatterns…

Unifying approachs has its own beauty.

why then, a message bus?

Message bus allow to offer decoupled interfaces, based in Events/Messages.

No callbacks, no request-reply, producers and consumers are decoupled.

Off-the-shelf communication patterns: topics, queues, ...

is it for me?

Probably not. Message bus is not everybody’s cup of tea.

If your platform is growing a lot in terms of load and/or complexity then it will help.

can we now start with the tech?

This is one possible way to communicate all your applications.

postal.js

jsmodule

jsmodule

jsmodule

RabbitMQ

STOMP over

Websokets (SockJS)

μService μService μService

RabbitMQ

RabbitMQ is a Message Broker implementing of the AMQP protocol. [4]

Fast and easy to use.

Open source :-)

Almost certainly it is supported in your language /

platform

Very advanced concepts:

● Messaging: exchanges, queues, routing, …● Built-in clustering and replication

[4] http://www.rabbitmq.com

Postal.js

JS pub/sub library supporting some advanced subscription features [5]

➔ in-memory message bus - very loosely inspired by AMQP

➔ runs in the browser, or on the server using node.js➔ only pub/sub, no queues➔ opensource (> 1K in github)

[5] https://github.com/postaljs/postal.js

javascript

Javascript is THE full-stack language: runs on

the client, server, databases and even on a toaster [6]

[6] http://bit.ly/1uX9s44

In our sample game:

➔ node.js: μ-services

➔ angular: almost magical binding

.js

STOMP SockJS

[7] http://stomp.github.io/

[8] https://github.com/sockjs

[9] http://www.rabbitmq.com/web-stomp.html

STOMP Simple Text

Orientated Messaging

Protocol [7].

STOMP clients communicate

with any STOMP message

broker (eg. RabbitMQ).

SockJS is a browser JS library that provides a WebSocket-like object [8]

SockJS uses native WebSockets or a variety of browser-specific transport protocols.

RabbitMQ provides a plugin that implements STOMP over SockJS: Web-Stomp plugin [9].It is very simple to setup and use.

full-stack-bus ballgame example

application example: multiplayer ping-pong

[10] https://github.com/javierarilos/full-stack-bus-ballgame

postal.js

classificati

on

gamelog

ball mgmt

score aggregatorμService

ballgame UX

aggregated scores and

classification gamelog

playfield

rabbit->postal

rabbit->postal

logical structure & messages

ball management classification gamelogball managementball management

classificationclassification

score aggregator

gameloggamelog

topic/ballgamequeue/balls

sendBallreceiveBall

single.score

single.*

aggregated.scores

single.score

aggregated.scores

rabbit->postal

N x Browser

RabbitMQ

Node.js

gameloggameloggame management

single.new-player

single.pong single.ping single.ping-fail single.ball-picked

understood, show me the code!!!!

➔ RabbitMQ connection and subscriptions

http://bit.ly/1Gy7JcR#L140

➔ postal.js subscriptions

http://bit.ly/1Gy7JcR#L177

➔ routing msgs: RabbitMQ => postal.js

http://bit.ly/1Gy7JcR#L133

➔ sending a message to RabbitMQ

http://bit.ly/1Gy7JcR#L117

➔ aggregate scores μ-service

http://bit.ly/1Gy9V4f

we are done with the full stack bus thing...

thank you for your attention!

media used. thanks to:

➔ Quentin Lebourgeois https://www.flickr.com/photos/quentinlebourgeois/5514792500/in/photostream/➔ pargon https://flic.kr/p/4J3Yqo➔ chriscroninimages www.flickr.com/photos/chriscroninimages/29963364➔ Jim Landon https://flic.kr/p/p3zyZv