AggregateRoot<TState extends State> class abstract

Base class for aggregate roots in domain-driven design Combines PersistentActor with domain logic and command processing

Inheritance

Constructors

AggregateRoot({required String aggregateId, required String aggregateType, required EventStore eventStore, CommandHandlerRegistry<TState>? commandHandlers, EventHandlerRegistry<TState>? eventHandlers})
Create an aggregate root with the specified aggregate ID and type

Properties

aggregateId → String
The aggregate ID for this aggregate root
no setter
aggregateType → String
The aggregate type for this aggregate root
no setter
commandHandlers → CommandHandlerRegistry<TState>
Command handler registry for this aggregate
no setter
currentState → TState
Current state of the aggregate (non-nullable) Throws if the aggregate hasn't been initialized
no setter
eventHandlers → EventHandlerRegistry<TState>
Event handler registry for this aggregate
no setter
eventStore → EventStore
Current event store instance
no setterinherited
hashCode → int
The hash code for this object.
no setterinherited
isInitialized → bool
Whether the aggregate has been initialized with state
no setter
isRecovered → bool
Whether this actor has completed recovery
no setterinherited
isRecovering → bool
Whether this actor is currently recovering from events
no setterinherited
persistenceId → String
Unique identifier for this persistent actor Used to store and retrieve events from the event store
no setterinherited
recoveryComplete → Future<void>
Future that completes when recovery finishes.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
sequenceNumber → int
Current sequence number for this actor Incremented with each persisted event
no setterinherited
state → TState?
Current state of the aggregate Returns null if the aggregate hasn't been initialized yet
no setter

Methods

applyEvent(TState currentState, Event event) → TState
Apply an event to the current state and return the new state This is the core method for event sourcing state transitions
canApplyEvent(Event event) → bool
Check if the aggregate can apply a specific event Override in subclasses for custom event routing
canHandleCommand(Command command) → bool
Check if the aggregate can handle a specific command Override in subclasses for custom command routing
checkConcurrency(int expectedVersion) → Future<void>
Check optimistic concurrency control with expected version Public method for explicit concurrency checking
commandHandler(Command command) → Future<void>
Process a command through the full pipeline This is the main entry point for command processing.
override
createInitialState() → TState
Create the initial state for this aggregate Override in subclasses to provide the initial state
createSnapshot() → Future<void>
Create a snapshot of current state Override to provide custom snapshot logic
inherited
ensureStateInitialized() → void
Initialize the aggregate state This is a protected method that subclasses can use when overriding eventHandler to ensure state is initialized before processing events (replicating base class behavior)
eventHandler(Event event) → void
Apply an event to update the aggregate state This is called during both command processing and recovery
override
getAggregateInfo() → AggregateInfo
Get aggregate information for debugging and monitoring
getBusinessRuleViolations(TState state) → List<String>
Get business rule violations for the current state Override in subclasses to provide specific violation messages
getSnapshotState() → Future
Get the current state for snapshot creation
override
handleCommand(TState currentState, Command command) → Future<List<Event>>
Handle a command and generate events This is the core method for command processing
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
onCommandFailure(Command command, dynamic error) → Future<void>
Called when command processing fails Override to handle command failures
inherited
onCommandProcessed(Command command, List<Event> events) → Future<void>
Called after a command has been successfully processed Override to perform post-command processing actions
onError(Object error, StackTrace stackTrace) → void
Called when an error occurs.
inherited
onEventApplicationFailure(Event event, dynamic error) → void
Called when event application fails Override to handle event application failures
onEventApplied(Event event, TState newState) → void
Called after an event has been applied to the state Override to perform post-event application actions
onMessage(dynamic message) → Future<void>
Handle incoming messages with command/event routing
inherited
onMessageDropped(dynamic message) → Future<void>
Called when a message is dropped because recovery timed out or failed. Override to send error responses, log, or enqueue for retry.
inherited
onPersist(Event event) → Future<void>
Called after successful event persistence Override to perform post-persistence actions
inherited
onPersistBatch(List<Event> events) → Future<void>
Called after successful batch event persistence Override to perform post-persistence actions for batches
inherited
onPersistBatchFailure(List<Event> events, dynamic error) → Future<void>
Called when batch event persistence fails Override to handle batch persistence failures
inherited
onPersistFailure(Event event, dynamic error) → Future<void>
Called when event persistence fails Override to handle persistence failures
inherited
onRecover() → Future<void>
Called at the start of recovery process Override to perform custom recovery initialization
inherited
onRecoveryComplete() → Future<void>
Called when recovery is complete Override to perform post-recovery initialization
inherited
onRecoveryFailure(dynamic error) → Future<void>
Called when recovery fails Override to handle recovery failures
inherited
onReplay(Event event) → Future<void>
Called for each event during replay Override to perform custom replay logic
inherited
onSnapshot(dynamic snapshotState, int sequenceNumber) → Future<void>
Restore state from snapshot during recovery
override
onSnapshotCreated(dynamic state, int sequenceNumber) → Future<void>
Called when a snapshot is created Override to perform post-snapshot actions
inherited
onSnapshotRestorationFailure(dynamic snapshotData, int sequenceNumber, dynamic error) → Future<void>
Called when snapshot restoration fails Override to handle snapshot restoration failures
onSnapshotRestored(TState state, int sequenceNumber) → Future<void>
Called after state has been restored from a snapshot Override to perform post-snapshot restoration actions
persistEvent(Event event) → Future<void>
Persist an event to the event store Events are immutable and stored permanently
inherited
persistEvents(List<Event> events) → Future<void>
Persist multiple events atomically All events succeed or all fail together
inherited
postStop() → void
Called when the actor is stopped.
inherited
preStart() → void
Called when the actor is started.
override
queryHandler(dynamic message) → Future<void>
Handles incoming queries or other non-persistent messages.
inherited
registerHandlers() → void
Register command and event handlers for this aggregate Override in subclasses to register domain-specific handlers
replay(List<Event> events) → void
Replay events to rebuild aggregate state Used during recovery and testing
restoreFromSnapshot(dynamic snapshotData, int sequenceNumber) → Future<TState>
Restore state from snapshot data Override in subclasses to provide custom restoration logic
restoreStateFromMap(Map<String, dynamic> map, int sequenceNumber) → Future<TState>
Restore state from a map representation Override in subclasses to provide custom map restoration
toString() → String
A string representation of this object.
override
validateBusinessRules(TState state) → bool
Validate business rules for the current state Override in subclasses to implement domain-specific validation

Operators

operator ==(Object other) → bool
The equality operator.
inherited