Event Sourcing in Laravel (Full Stack Ghent)

Transcript

1. Getting started with
   event sourcing in Laravel
   

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2. About me
   Freek Van der Herten
   Partner & developer at Spatie
   @freekmurze
   murze.be
   ohdear.app
   

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3. Spatie
   Laravel, front-end development
   Since 2003
   9 awesome human beings
   

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4. Open Source 

   Software
   

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5. We create a lot of it
   ± 200 packages on Packagist
   ± 2,000,000 downloads a month
   ± 30,000,000 total downloads
   All Postcardware!
   

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6. Highlights
   Popular
   laravel-backup
   laravel-medialibrary
   laravel-permission
   New
   laravel-query-builder
   laravel-blade-x
   

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7. https://spatie.be/open-source
   

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8. https://spatie.be/open-source/postcards
   

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9. Let's talk about
   event sourcing
   

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10. Talk overview
    Theory
    Projectors demo
    Aggregates demo
    

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11. Theory
    

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12. Traditional application
    Write data in database
    An update means overwriting the old data
    The old data cannot be accessed anymore
    

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13. APPLICATION
    DATABASE
    TABLE
    value X
    

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14. APPLICATION
    DATABASE
    TABLE
    value X
    value Y
    

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15. Event Sourced Application
    The application will fire off events
    Events will get written in a dedicated store
    Events are passed to consumers that create projections
    Aggregate, Aggregate Root...
    

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16. APP EVENTS
    Event
    Event 1
    

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17. APP EVENTS
    Event
    Event 1
    Event 2
    

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18. APP EVENTS
    Event
    Event 1
    Event 2
    Event 3
    

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19. APP
    CONSUMER
    EVENTS
    PROJECTION
    Event
    Event 1
    Event 2
    Event 3
    

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20. APP
    CONSUMER
    CONSUMER 2
    EVENTS
    PROJECTION
    Event
    Event 1
    Event 2
    Event 3
    ANOTHER PROJECTION
    

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21. APP
    CONSUMER
    CONSUMER 2
    EVENTS
    PROJECTION
    Event
    Event 1
    Event 2
    Event 3
    ANOTHER PROJECTION
    

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22. APP
    CONSUMER
    CONSUMER 2
    EVENTS
    PROJECTION
    Event
    Event 1
    Event 2
    Event 3
    Event 4
    ANOTHER PROJECTION
    

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23. Event Sourced Application
    Auditing requirements
    Extra reports needed
    Recording the unhappy path
    There is some setup required
    

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24. Laravel 

    Event Projector
    

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25. Laravel Event Projector
    Package made by Spatie
    Aggregates, Projectors & Reactors
    Beautifully integrated into Laravel
    Easy to get started with
    

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26. https://docs.spatie.be/laravel-event-projector
    

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27. Demo
    

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28. Aggregates
    

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35. Demo
    

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36. In closing
    

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37. Summary
    Laravel Event Projector
    Easy to use package to get started with event sourcing
    Projectors
    Replay capabilities
    Aggregates
    

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38. Writes are harder, reads are easier
    

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39. Event sourcing makes the easy things harder…
    …and the harder things easier
    — Frank De Jonge
    

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40. Larabank
    github.com/spatie/larabank-traditional
    github.com/spatie/larabank-event-projector
    github.com/spatie/larabank-event-projector-aggregates
    github.com/spatie/larabank-eventsauce
    

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41. Resources
    kickstarter.engineering/event-sourcing-made-simple-4a2625113224
    github.com/spatie/laravel-event-projector
    github.com/eventsaucephp/eventsauce
    github.com/prooph
    

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42. Thank you!
    speakerdeck.com/freekmurze/event-sourcing-full-stack-ghent
    spatie.be/open-source
    murze.be
    ohdear.app
    

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