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/)

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10. Actor Behavior Aggregate Event View Command
11. Actor Behavior Aggregate Event Command
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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
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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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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