gru_emoney_token-factory/api/shared/events/event-bus.ts

/**
 * Event bus client for publishing and subscribing to events
 * Supports Kafka and NATS
 */

import { EventEmitter } from 'events';

export interface EventEnvelope {
  eventId: string;
  eventType: string;
  occurredAt: string;
  actorRef?: string;
  correlationId?: string;
  payload: any;
  signatures?: Array<{ signer: string; signature: string }>;
}

export class EventBusClient extends EventEmitter {
  private kafkaClient: any;
  private natsClient: any;
  private subscribers: Map<string, Set<(data: any) => void>> = new Map();

  constructor(config: { kafka?: any; nats?: any }) {
    super();
    // TODO: Initialize Kafka or NATS client based on config
  }

  /**
   * Publish an event to the event bus
   */
  async publish(topic: string, event: EventEnvelope): Promise<void> {
    // TODO: Publish to Kafka or NATS
    // Validate event schema before publishing
    this.emit('published', { topic, event });
  }

  /**
   * Subscribe to events from a topic
   */
  subscribe(topic: string): AsyncIterator<any> {
    // TODO: Return async iterator for GraphQL subscriptions
    const iterator = this.createAsyncIterator(topic);
    return iterator;
  }

  private createAsyncIterator(topic: string): AsyncIterator<any> {
    // TODO: Create async iterator that yields events from topic
    return {
      async next() {
        // TODO: Wait for next event from topic
        return { done: false, value: null };
      },
      [Symbol.asyncIterator]() {
        return this;
      },
    };
  }

  /**
   * Close connections
   */
  async close(): Promise<void> {
    // TODO: Close Kafka/NATS connections
  }
}

export const eventBusClient = new EventBusClient({
  // TODO: Load config from environment
});