Domain Driven Design with CQRS and Event Sourcing

Domain Driven Design, CQRS and Event Sourcing presentation made during Node.js Paris meetup (https://www.meetup.com/fr-FR/Nodejs-Paris/events/263358579/)

Transcript

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2. ❤
   

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5. !
   if(this.authProvider.validate(token)) {
   this.service
   .send(session.get("user_basket"));
   }
   

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6. • ⚠
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8. •
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9. !=
   

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10. Actor
    Behavior
    Aggregate
    Event
    View
    Command
    

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11. Actor Behavior
    Aggregate Event
    Command
    
    

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15. •
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16. CQRS
    GetBalance
    Query
    Deposite
    Command
    GetAllOperation
    Query
    Withdraw
    Command
    … …
    Dispatcher
    Read
    DB
    Dispatcher
    QueryHandler CommandHandler
    Write
    DB
    Validation Plugin
    Monitoring Plugin
    Cache Plugin
    …
    ⚠ Eventual consistency
    

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18. • What is Event Sourcing?
    • Capture all domain changes as a sequence of events (stream)
    • Every changes in the domain are represented by events
    • Events are immutable
    • Event Store will be the single point of truth
    • Useful for:
    • Auditing
    • Debug
    • Fix inconsistency
    • Description of the pattern by Martin Fowler:
    https://martinfowler.com/eaaDev/EventSourcing.html
    Event Sourcing
    

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19. •
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20. CQRS & Event Sourcing
    GetBalance
    Query
    Deposite
    Command
    GetAllOperation
    Query
    Withdraw
    Command
    … …
    Dispatcher
    Read
    DB
    Dispatcher
    QueryHandler CommandHandler
    Event
    Store
    Projection Projection
    Aggregate
    State
    Events Behaviors
    

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22. ●
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24. ☺
    

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