Interface IProjectionMethodInvoker

Namespace

Stratara.Projections.Abstractions

Assembly

Stratara.Projections.dll

Reflection-based discovery + invocation helper that locates a projection's HandleAsync methods and caches compiled delegates for hot-path dispatch.

public interface IProjectionMethodInvoker

Extension Methods

FieldChangedEventExtensions.ApplyPropertyChanged<TAggregate>(TAggregate, FieldChangedEvent<TAggregate>)

EventStream.ApplyEvents(object, IReadOnlyList<IEvent>)

Remarks

Implementations are expected to use process-lifetime caches keyed by (projectionType, eventType); the cache plateaus once every registered projection has been dispatched against every event type it declares a handler for.

Methods

GetOrCreateDelegate(IProjection, Type)

Returns a compiled delegate that invokes the projection's HandleAsync(eventType, CancellationToken) overload, or the cached no-op if the projection declares no handler for the type.

Func<IProjection, object, CancellationToken, Task> GetOrCreateDelegate(IProjection projection, Type eventType)

Parameters

projection IProjection

The projection that owns the handler.

eventType Type

The event payload type (or wrapping IEvent<TEvent> type) to look up.

Returns

Func<IProjection, object, CancellationToken, Task>

GetOrCreateRelevantEventTypes(IProjection)

Returns the distinct event types the projection declares HandleAsync overloads for, computing them on first call and caching thereafter.

Type[] GetOrCreateRelevantEventTypes(IProjection projection)

Parameters

projection IProjection

The projection to inspect.

Returns

Type[]

IsNoOp(Func<IProjection, object, CancellationToken, Task>)

Returns true if the supplied delegate is the cached no-op (i.e. the projection declares no handler for that event type).

bool IsNoOp(Func<IProjection, object, CancellationToken, Task> delegateOperation)

Parameters

delegateOperation Func<IProjection, object, CancellationToken, Task>

The delegate to test.

Returns

bool