This document outlines principles of reactive programming as presented in a talk. It defines reactive programming as a paradigm oriented around data flows and propagation of change. The main principles discussed are being message-driven, using non-blocking and asynchronous operations, and implementing back pressure in data flows. Code examples and links are provided to illustrate asynchronous programming and the actor model as approaches to reactive programming. The talk argues that reactive programming raises the level of abstraction to focus on interdependent events rather than implementation details.

1. –Nelson Pascoal
“Reactive Programming Principles”
make -> tasks -> flow
http://www.kotive.com

3. Is not what this talk is about

4. Wikipedia: too generic and theoretical
Stackoverflow: canonical & not suitable for
beginners
Reactive Manifesto: something you would give
to managers or business people
What is Reactive Programming?

5. Dilbertesque Definition
In computing, reactive programming is a programming
paradigm oriented around data flows and the propagation
of change. This means that it should be possible to express
static or dynamic data flows with ease in the programming
languages used, and that the underlying execution model
will automatically propagate changes through the data flow.

6. Dilbertesque Definition
In computing, reactive programming is a programming paradigm
oriented around data flows and the propagation of change. This
means that it should be possible to express static or dynamic data
flows with ease in the programming languages used, and that the
underlying execution model will automatically propagate changes
through the data flow.

7. Reactive programming is programming with
asynchronous data streams
(Nothing new, event buses or your typical click events are event streams.)

8. Reactive programming is programming with
asynchronous data streams
(Nothing new, event buses or your typical click events are event streams.)
Abstractions for handling concurrent
asynchronous processing within a system

11. [8, 3, 1, 6, 4, 7, 10, 14, 13]

12. [8, 3, 1, 6, 4, 7, 10, 14, 13]
[8,[3,[1,[],[]],[6,[4,[],[]],[7,[],[]]]],[10,[14,[13,[],[]],
[]],[]]]

13. Main principles of Reactive Programming
Message Driven
Non-blocking IO
Asynchronous
and Back Pressure

14. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO
Asynchronous
and Back Pressure

15. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO
Asynchronous
and Back Pressure

16. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO
Asynchronous http://tinyurl.com/nqnakz6 & http://tinyurl.com/pz869qe
and Back Pressure

17. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO
Asynchronous http://tinyurl.com/nqnakz6 & http://tinyurl.com/pz869qe
and Back Pressure

18. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO
Asynchronous http://tinyurl.com/nqnakz6 & http://tinyurl.com/pz869qe
and Back Pressure

19. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO https://github.com/libuv/libuv & http://tinyurl.com/mwhhx5l
Asynchronous http://tinyurl.com/nqnakz6 & http://tinyurl.com/pz869qe
and Back Pressure

20. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO https://github.com/libuv/libuv & http://tinyurl.com/mwhhx5l
Asynchronous http://tinyurl.com/nqnakz6 & http://tinyurl.com/pz869qe
and Back Pressure

21. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO https://github.com/libuv/libuv & http://tinyurl.com/mwhhx5l
Asynchronous http://tinyurl.com/nqnakz6 & http://tinyurl.com/pz869qe
and Back Pressure

22. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO https://github.com/libuv/libuv & http://tinyurl.com/mwhhx5l
Asynchronous http://tinyurl.com/nqnakz6 & http://tinyurl.com/pz869qe
and Back Pressure http://tinyurl.com/pbs5yq9

23. Main principles of Reactive Programming
Message Driven http://tinyurl.com/prr8j43
Non-blocking IO https://github.com/libuv/libuv & http://tinyurl.com/mwhhx5l
Asynchronous http://tinyurl.com/nqnakz6 & http://tinyurl.com/pz869qe
and Back Pressure http://tinyurl.com/pbs5yq9

24. Reactive Programming raises the level of
abstraction of your code so you can
focus on the interdependence of events
that define the business logic, rather
than having to constantly fiddle with a
large amount of implementation details.
http://tinyurl.com/mwhhx5l

25. Actor model is reactive
• Message driven
• Asynchronous
• Can be used to isolate blocking IO
(careful with threading)
• Correct message handling can give
you back pressure (very manual
though)

26. More in line with how the world works
make -> tasks -> flow

27. Let's look at an example.
A coffee shop simulator :)

28. THANK YOU
https://github.com/foomip/coffeeshop-ruby
@foomip
http://www.kotive.com