Struct EventSourcedOrchestratingAggregate

pub struct EventSourcedOrchestratingAggregate<'a, C, S, E, Repository, Version, Error>
where
    Repository: EventRepository<C, E, Version, Error>,
{ /* private fields */ }

Orchestrating Event Sourced Aggregate. It is using a Decider and Saga to compute new events based on the current events and the command. If the decider is combined out of many deciders via combine function, a saga could be used to react on new events and send new commands to the decider recursively, in single transaction. It is using a EventRepository to fetch the current events and to save the new events. Generic parameters:

• C - Command
• S - State
• E - Event
• Repository - Event repository
• Version - Version/Offset/Sequence number
• Error - Error

Implementations

impl<'a, C, S, E, Repository, Version, Error> EventSourcedOrchestratingAggregate<'a, C, S, E, Repository, Version, Error>

where Repository: EventRepository<C, E, Version, Error> + Sync, C: Sync, S: Sync, E: Sync + Clone, Version: Sync, Error: Sync,

pub fn new( repository: Repository, decider: Decider<'a, C, S, E, Error>, saga: Saga<'a, E, C>, ) -> Self

Creates a new instance of EventSourcedAggregate.

pub async fn handle(&self, command: &C) -> Result<Vec<(E, Version)>, Error>

where E: Identifier, C: Identifier,

Handles the command by fetching the events from the repository, computing new events based on the current events and the command, and saving the new events to the repository.

Trait Implementations

impl<C, S, E, Repository, Version, Error> EventRepository<C, E, Version, Error> for EventSourcedOrchestratingAggregate<'_, C, S, E, Repository, Version, Error>

where Repository: EventRepository<C, E, Version, Error> + Sync, C: Sync, S: Sync, E: Sync, Version: Sync, Error: Sync,

async fn fetch_events(&self, command: &C) -> Result<Vec<(E, Version)>, Error>

Fetches current events, based on the command.

async fn save(&self, events: &[E]) -> Result<Vec<(E, Version)>, Error>

Saves events.

async fn version_provider(&self, event: &E) -> Result<Option<Version>, Error>

Version provider. It is used to provide the version/sequence of the event. Optimistic locking is useing this version to check if the event is already saved.