Scale Node

8/10/2019 Scale Node

1/30

SCALING NODE.JSAPPLICATIONS WITH

REDIS, RABBITMQ & COTE.JS

Armagan AmcalarJSIST 2014, Istanbul

Sep 27th, 2014


2/30

WHO AM I?

Armagan AmcalarCo-founder, Chief Software Architect

dashersw

Startup Kitchen

AUTHORED ON GITHUB

pedalboard.js

tartJS

geneJS

cote

semaver

jira-bot

HOBBY PROJECTS

pedals.io

trax.io


3/30

NODE.JS

We love it.

We develop all kinds of software with it.

We love to daemonize it.


4/30

THE PROBLEMIt doesn't scale well.

Programming model encourages stateful app design

Works great as single process

Works OK as a cluster


5/30

WHAT'S NEXT?What if you need more computing power?

How about horizontal scalability?


6/30

CURRENT SOLUTION

NGINX

NODE-HTTP-PROXY

REVERSE PROXY


7/30

NGINXEasy to set up if you're familiar

with nginx

Hard to maintain

Yet another technology

dependency

NODE-HTTP-PROXYHard to set up even if you're

familiar

Hard to maintain

Very low level


8/30

WE NEED A DIFFERENT SOLUTION.Because we have more problems

We're not just building express apps

We were programming the DOM, we need that flexibility


9/30

MORE PROBLEMS?Be fast with your API response

Asynchronous processing (e.g., analytics)You may need to scale very dynamically

Fault tolerance

THE YEAR'S 2014, WHERE ARE THE EVENTS?


10/30


11/30


12/30

MICROSERVICESSeparate code base

Multi processes for each service

A bug in a service crashes only that service

Consumes minimal resources

Scales well, needs minimal additional resources

Supports event-driven architecture

Requestresponse flow breakdown

Hard to manage


13/30

EVENT-DRIVEN ARCHITECTURE

PUB-SUB PATTERNOBSERVER PATTERN


14/30

PUB-SUB PATTERN

Just like DOM events, what we're used to build.

Instead of click events, you have custom events (e.g. in jQuery)

Instead of DOM element interaction, you have daemon

interaction


15/30

OBSERVER PATTERNFirst-of-its-kind event driven pattern

You an object property, not an arbitrary event

Like all your click handlers have to have the same name

Limits possibilities


16/30

ENTER REDIS

Originally a NoSQL database

Key-value pair server with lots of great features like sets, etc.

Pub-sub capability

Supports events based on channels and patterns

Very cool node.js library


17/30

A REDIS PUBSUB-BASED ARCHITECTURE

redisd1

d4

d3

d2

publishes foo

notifies of foo

notifies of foo

notifies of foo

client request

session storage

logs

API


18/30

EXAMPLE

varredis = require('redis'),

client = redis.createClient(6379, '127.0.0.1');

client.publish('request', JSON.stringify({

body: 'some cool request'

}));

varredis = require('redis'),

logger = redis.createClient(6379, '127.0.0.1');

logger.subscribe('request');

logger.on('message', function(channel, message) { if(channel == 'request')

console.log(JSON.parse(message));

});

Client

Logger


19/30

QUICK DEMO


20/30

ENTER RABBITMQA message broker for distributed applications

Like redis pubsub, with heavy focus on additional features

such as flexible message routing

work queues, topics, etc.QoS management

round robin load balancing

message acks

rate limiting

unfriendly node.js library


21/30

WORK QUEUES

REMOTE PROCEDURE CALLS


22/30

EXAMPLE WORK QUEUEvaramqp = require('amqp'),

connection = amqp.createConnection(),

workId = 0;

connection.on('ready', function() {

connection.queue('work_queue', {autoDelete: false, durable: true}, function(queue) {

setInterval(function() {

connection.publish('work_queue', 'message #'+ ++workId, { deliveryMode: 2});

console.log('sent message #'+ workId);

}, 1000);

});

});

varamqp = require('amqp'),

connection = amqp.createConnection();

connection.on('ready', function() {

connection.queue('work_queue', {autoDelete: false, durable: true}, function(queue) {

queue.subscribe({ack: true, prefetchCount: 1}, function(msg) {

varbody = msg.data.toString('utf-8');

console.log("received", body);

queue.shift(); // basic_ack equivalent

});

});

});


23/30

QUICK DEMO


24/30

ENTER COTE.JSnode.js framework for fault tolerant, distributed apps

developed at Startup Kitchenpartially funded by TUBITAK


25/30

COTE.JS FEATURES

auto-discovery

mesh network, peer-to-peer communication

pubsub pattern

requester/responder patternclient-side communication with websockets

load balancing with different strategies

daemon monitor


26/30

EXAMPLE ARCHITECTURE


27/30

EXAMPLE PUB-SUB IMPLEMENTATIONvarPublisher = require('cote').Publisher,

publisher = newPublisher({

name: 'publisher',

broadcasts: ['update']

}),

workId = 0;

publisher.on('ready', function() {

setInterval(function() {

console.log('emitting', ++workId);

publisher.publish('update', workId);

}, 3000);});

varSubscriber = require('cote').Subscriber,

subscriber = newSubscriber({

name: 'subscriber'

});

subscriber.on('update', function(message) {

console.log('update', message);

});


28/30

QUICK DEMO


29/30

CONCLUSION

With Redis, RabbitMQ or cote.js we can;

Apply sophisticated programming paradigmsScale nearly infinitely

Have fault-tolerant systems


30/30

THANK YOU!

CONTRIBUTE TO COTE.JS

github.com/dashersw/cote

LET'S KEEP IN TOUCH!

Armagan Amcalar

twitter:github:

blog:

[email protected]

@aamcalardashersw

arm.ag

examples at https://github.com/dashersw/node-scale

Documents

Scale Node