Onion-like app architecture

Learn how to architect an entire app – from UI, through user / data flows and transactions down to data storage and delivery – in independent, interchangeable layers. With layers that can be freely combined as needed, with no or minimal disruption to the rest of app. Just like an onion. You will learn that MVC is excellent, if employed properly. You will learn how to use Coordinators without delegates and with truly minimal UIKit extensions. Learn about an approach suitable for iOS teams of one and teams of 1000 developers. For 5 screen apps and for 200+ UIViewController behemots.

https://github.com/radianttap/Coordinator

https://github.com/radianttap/Spotifier

Video: https://www.youtube.com/watch?v=kD8dRvEQ5II

Transcript

1. Aleksandar Vacić
   @radiantav
   O N I O N - L I K E A P P A R C H I T E C T U R E
   App Builders 2019
   

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2. Aleksandar Vacić
   Belgrade, Serbia
   radianttap.com
   aplus.rs
   @radiantav
   

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3. Why architecture?
   architecture?
   

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4. HomeController
   ProductDetailsController
   ProductsController
   

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6. Architecture of complex apps
   is ever evolving, quite often
   in unforseen ways.
   

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8. Fashion SPORTS BETTING Sales
   

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9. · 100+ screens (few dozen are multi-screen flows)
   · multiple external services
   · 10+ languages (with runtime updates)
   · 20+ markets in Europe, Africa and S. America
   · iOS, tvOS, watchOS, widgets
   · Notifications, deep links, home screen actions
   SPORTS BETTING
   · Unpredictable future expansion
   

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10. Connect to web services
    Import into local storage
    Cache temporary data
    Directly target any screen, at any depth
    Transform any 3rd party data model into my own
    Multi-screen user flow
    Multi-service data flow
    Multi-OS reusability
    Reading data is always super performant
    c h a l l e n g e s
    

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11. Build complex system that works
    by first building a simple system
    that works.
    Break complex, multi-faceted flows
    into self-sufficient steps.
    Then compose them back.
    p r i n c i p l e s
    

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12. DATA MODEL
    

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13. Data Source
    Data Delivery
    Data Storage
    DATA MODEL
    

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14. Data Source
    Data Delivery
    Data Storage
    web service, bundled file,
    cached download
    URLSession, FileManager,
    Authentication, Encryption
    Core Data, mobile db,
    in-memory, file / custom store
    

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15. Data
    UI
    

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16. Data
    UI
    

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17. Data
    UI
    

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19. Data
    UI
    

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20. Data
    UI
    

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21. Data
    UI
    

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22. UI
    Data
    

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23. UI
    Data
    

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24. Data
    UI
    UI Coordinators
    

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25. UI
    UI Coordinators
    Data
    

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26. UI
    UI Coordinators
    Middleware
    Data
    

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27. Data Source
    Data Delivery
    Data Storage
    UI
    UI Coordinators
    Middleware
    L A Y E R S
    DATA MODEL
    

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28. O N I O N
    It resembles , isn’t it?
    

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29. O N I O N
    G A R L I C
    It resembles , isn’t it?
    

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30. Data Source
    Data Delivery
    Data Storage
    UI
    UI Coordinators
    Middleware
    L A Y E R E D
    DATA MODEL
    KEEP IT
    & SIMPLE
    

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31. Coordinator

    Advanced implementation of said pattern in
    Swift, including care-free messaging through
    UIResponder chain.
    Avenue

    URLSession wrapper, handles boilerplate,
    enables seamless usage with
    Operation(Queue).
    Ambar

    Custom Core Data stack with automatic merge
    of background imports into main MOC.
    / radianttap
    

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32. DEMO
    radianttap
    / Spotifier
    /
    

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33. What were my problems, or…
    KILS Architecture Benefits
    Builds on system frameworks
    ɠ
    Rapid iterations
    ɡ
    Painless refactoring
    ɢ
    Low maintenance cost
    ɣ
    

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34. / radianttap
    SpeakerDeck.com / radianttap
    aplus.rs
    Aleksandar Vacić, radianttap.com
    @radiantav
    SLIDES
    DEV BLOG
    CONTACT
    

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