what every programmer should know about distributed systems

What Every Programmer Should

Know About Distributed Systems

Friday, November 11, 11

What Every Programmer Could

Possibly Want To Know About Me

Friday, November 11, 11

Friday, November 11, 11

Friday, November 11, 11

Friday, November 11, 11

Friday, November 11, 11

What Every Programmer Should

Know About Distributed Systems

Friday, November 11, 11

IDefinition

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A distributed system consists of multiple autonomous applications that interact with each other to achieve a common goal.

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Photo by Matt Gibson

IICode Granularity

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print "Converting Celsius or Fahrenheit? "option = gets[0,1].downcasecase optionwhen "c" print "Convert C: " celsius = gets.to_i fahrenheit = celsius * 9/5 + 32 puts "#{celsius}C = #{fahrenheit}F"when "f" print "Convert F: " fahrenheit = gets.to_i celsius = (fahrenheit - 32) * 5/9 puts "#{fahrenheit}F = #{celsius}C"end

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def main convert(pick_unit)end

def pick_unit print "Convert Celsius ou Fahrenheit? " gets[0,1].downcaseend

def convert(unit) case unit when "c": convert_celsius when "f": convert_fahrenheit endend

...

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Ideal Granularity

Somewhere in between

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Units & OO

• Methods

• Classes

• Packages

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Units & Languages

• Ruby

• Java

• PHP

# sinatra.rbmodule Sinatra class Application ... class Event ... module Streaming class FileStreamer ...

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Units & Languages

• Ruby

• Java

• PHP$ javac Sinatra.javasinatra.java:5: class Application is public, should bedeclared in a file named Application.java

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Units & Languages

• Ruby

• Java

• PHP

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Units & Architecture

• Applications

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From Google Maps

IIIThe Evolution of Óbidos

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Heroku

• Instance management

• Billing & invoices

• Process orchestration

• Public API

Friday, November 11, 11

Heroku

• Instance management

• Billing & invoices

• Process orchestration

• Public API

Friday, November 11, 11

Heroku

• Instance management

• Billing & invoices

• Process orchestration

• Public API

Friday, November 11, 11

Heroku

• Instance management

• Billing & invoices

• Process orchestration

• Public API

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IVDeveloping the Medium

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Problem:

?

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Share the Database

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Share the DatabaseDO NOT

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REST

RestClient.get "host/users/1" get "/users/:id" do |id| user = User.find(id) user.to_jsonend

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MQ

AMQP.start(:host => "1.2.3.4") do q = MQ.new.queue("user.created") q.publish(:email => "pedro@heroku.com")end

AMQP.start(:host => "1.2.3.4") do q = MQ.new.queue("user.created") q.subscribe do |msg| ... endend

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VChallenges

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Challenges

• Versioning

• Testing

• Authentication

• Development environment

• Visual consistency

• Deploying

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Summary

1. Definition

2. Code Granularity

3. The Evolution of Óbidos

4. Developing the Medium

5. Challenges

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Thank you!

pedro@heroku.com

http://pedro.heroku.com

@ped

Friday, November 11, 11