customer-event-processor.ts

import { SendWelcomeMessageInteractor } from "../marketing/control/send-welcome-message";
import { CustomerEventNames, CreateCustomerEvent } from "../customer/entity/customer-event";
import { S3PutEvent, S3PutEventEntry } from "../s3/entity/put-event-entry";
import { DataLakeGateway } from "../datalake/boundary/datalake-gateway";

const dataLakeGateway = DataLakeGateway.newInstance();
const sendWelcomeMessageInteractor = SendWelcomeMessageInteractor.newInstance();

const extractEventIdAndEventName = (
  s3PutEventEntry: S3PutEventEntry
): { eventId: string; eventName: string } => {
  const eventKeyTokens: Array<string> = s3PutEventEntry.s3.object.key.split(
    "/"
  );
  const eventName = eventKeyTokens[0];
  const eventId = eventKeyTokens[1];
  return { eventId, eventName };
};

export const handler = async (s3PutEvent: S3PutEvent): Promise<void> => {
  for (const s3PutEventEntry of s3PutEvent.Records) {
      const { eventId, eventName } = extractEventIdAndEventName(
        s3PutEventEntry
      );

      if (eventName === CustomerEventNames.CUSTOMER_CREATED) {
        
        const eventPayload:CreateCustomerEvent = await dataLakeGateway.getEvent<CreateCustomerEvent>(eventid);
        
        const { customerEmail } = eventPayload;
    
        await sendWelcomeMessageInteractor.call(customerEmail};
      }
  }
};