How to signal that the transaction completed

When we're sure that the transaction has completed, the DomainEvents subject provides a method to notify all Observers of each Domain Event of its occurrence.

// shared/domain/events/DomainEvents.ts

export class DomainEvents {
  private static handlersMap = {};
  private static markedAggregates: AggregateRoot<any>[] = [];


   * @method dispatchEventsForAggregate
   * @static
   * @desc When all we know is the ID of the aggregate, call this
   * in order to dispatch any handlers subscribed to events on the
   * aggregate.

  public static dispatchEventsForAggregate(id: UniqueEntityID): void {
    const aggregate = this.findMarkedAggregateByID(id);

    if (aggregate) {

  private static removeAggregateFromMarkedDispatchList(
    aggregate: AggregateRoot<any>
  ): void {
    const index = this.markedAggregates.findIndex(a => a.equals(aggregate));
    this.markedAggregates.splice(index, 1);

   * @method dispatchAggregateEvents
   * @static
   * @private
   * @desc Call all of the handlers for any domain events on this aggregate.

  private static dispatchAggregateEvents(aggregate: AggregateRoot<any>): void {
    aggregate.domainEvents.forEach((event: IDomainEvent) =>

   * @method dispatch
   * @static
   * @desc Invokes all of the subscribers to a particular domain event.

  private static dispatch(event: IDomainEvent): void {
    const eventClassName: string =;

    if (this.handlersMap.hasOwnProperty(eventClassName)) {
      const handlers: any[] = this.handlersMap[eventClassName];
      for (let handler of handlers) {

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