groovy options for reactive applications - greach 2015
TRANSCRIPT
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Reactive Options for Groovy
Steve Pember
CTO, ThirdChannel
@svpember
Greach, 2015
What is ‘Reactive’?
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Possible Reactive Definitions• Reactive Programming
Imperative: A = B+C at that moment in time
Reactive: A = B+C whenever B or C change
values
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Possible Reactive Definitions• Reactive Programming
• Reactive Systems
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Possible Reactive Definitions• Reactive Programming
• Reactive Systems
• Reactive Streams / Reactive Extensions (Rx)
All 3 Are Different, But Related
… Today is About Reactive Systems
and Rx
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Agenda• Reactive Systems
• Reactive Streams / Reactive Extensions
• Reactive Groovy
• Demos
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Agenda• Reactive Systems
The Need For Reactive
(The Reactive Manifesto)
–Johnny Appleseed
“Type a quote here.”
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–Johnny Appleseed
“Type a quote here.”
–Johnny Appleseed
“Type a quote here.”
Need to Handle As Many Users As
Possible
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Reactive Systems• The Need for Reactive
• 4 Reactive Principles
–Johnny Appleseed
“Type a quote here.”
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Reactive Systems• The Need for Reactive
• 4 Reactive Principles
• Responsive
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Reactive Systems• The Need for Reactive
• 4 Reactive Principles
• Responsive
• Resilient
–Johnny Appleseed
“Type a quote here.”
Embrace Failure
Independent Things Fail
Independently
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Reactive Systems• The Need for Reactive
• 4 Reactive Principles
• Responsive
• Resilient
• Elastic (Scalable)
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Reactive Systems• The Need for Reactive
• 4 Reactive Principles
• Responsive
• Resilient
• Elastic (Scalable)
• Asynchronous Message-Driven
Events
Actors
–Johnny Appleseed
“Type a quote here.”
–Johnny Appleseed
“Type a quote here.”
Never Block
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Agenda• Reactive Systems
• Reactive Streams / Reactive Extensions
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Reactive Streams / Extensions• Originally out of Microsoft
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Reactive Streams / Extensions• Originally out of Microsoft
• Brought to JVM
–Johnny Appleseed
“Type a quote here.”
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Reactive Streams / Extensions• Originally out of Microsoft
• Brought to JVM
• Designed to Handle Messages Asynchronously Across Boundaries
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Reactive Streams / Extensions• Originally out of Microsoft
• Brought to JVM
• Designed to Handle Messages Asynchronously Across Boundaries
• Composable
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Reactive Streams / Extensions• Originally out of Microsoft
• Brought to JVM
• Designed to Handle Messages Asynchronously Across Boundaries
• Composable
• Hot / Cold
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Reactive Streams / Extensions• Originally out of Microsoft
• Brought to JVM
• Designed to Handle Messages Asynchronously Across Boundaries
• Composable
• Hot / Cold
• Backpressure
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Agenda• Reactive Systems
• Reactive Streams / Reactive Extensions
• Groovy Options
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A Few Groovy Options…• Akka
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A Few Groovy Options…• Akka
• Akka Streams
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Akka & Akka Streams• Definition of Reactive System
• Typesafe
• Actor-Based Concurrency
• Implemented Streams on Top of Actor Model
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A Few Groovy Options…• Akka
• Akka Streams
• RxJava / RxGroovy
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RxJava• Comes out of Netflix
• Part of reactivex.io
• Reactive Streams on the JVM
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A Few Groovy Options…• Akka
• Akka Streams
• RxJava / RxGroovy
• Ratpack
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• HTTP application server
• Non-opinionated
• Built on Reactive Streams, Netty, Java 8, Guava
• Fully embodies reactive
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A Few Groovy Options…• Akka
• Akka Streams
• RxJava / RxGroovy
• Ratpack
• Reactor
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• Reactive Streams
• Reactor Pattern
• Built on LMAX Ring Buffer / Disrupter
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VS
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What About Java 8 Streams?
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Java 8 Streams• Built into the language
• Meant for Finite Iterables
• Observables -> potentially infinite items, with back pressure
• “Pulling” vs “Pushing”
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Agenda• Reactive Systems
• Reactive Streams / Reactive Extensions
• Groovy Options
• Demos
Thank You!
Questions?@svpember
Image Credits• 1000ms Time To glass:
https://docs.google.com/presentation/d/1IRHyU7_crIiCjl0Gvue0WY3eY_eYvFQvSfwQouW9368/present?slide=id.g1e697bbb_0_7
• internet users in the world: http://www.internetlivestats.com/internet-users/
• internet users vs Facebook: https://medium.com/reactive-programming/what-is-reactive-programming-bc9fa7f4a7fc
• reactivex logo: https://www.stickermule.com/marketplace/2223-rx-reactive-extensions-logo-4
• cheetah: www.livescience.com/21944-usain-bolt-vs-cheetah-animal-olympics.html
• dominoes: https://www.flickr.com/photos/louish/5611657857/sizes/l/in/photostream/
• 300 / Spartans: http://www.300themovie.com/
• latop punch: http://walls4joy.com/wallpaper/730566-angry-laptops-punch
• mailman: http://thebrandtstandard.com/2013/02/09/u-s-post-office-to-end-saturday-letter-delivery-this-summer/
• actor system: http://letitcrash.com/post/30585282971/discovering-message-flows-in-actor-systems-with
• slow down: http://forthefamily.org/reminder-slow/