handler logic

gistfile1.txt

 async handleEvent(gesEvent) {
            logger.debug('handleEvent | checking event for idempotence');
            var idempotency = await readstorerepository.checkIdempotency(gesEvent.originalPosition, this.eventHandlerName);
            if (!idempotency.isIdempotent) {
                logger.debug('handleEvent | event is not idempotent');
                return;
            }
            logger.trace('handleEvent | event idempotent');

            try {
                logger.info('handleEvent | calling specific event handler for: ' + gesEvent.eventName + ' on ' + this.eventHandlerName);
                this.createNotification(gesEvent);
              
                this[gesEvent.eventName](gesEvent.data, gesEvent.metadata.continuationId);

                logger.trace('handleEvent | event Handled by: ' + gesEvent.eventName + ' on ' + this.eventHandlerName);
                readstorerepository.recordEventProcessed(gesEvent.originalPosition, this.eventHandlerName, idempotency.isNewStream);

            } catch (exception) {
                logger.error('handleEvent | event: ' + gesEvent.friendlyDisplay() + ' threw exception: ' + exception);

                this.responseMessage = eventmodels.notificationEvent("Failure", exception.message, gesEvent);

            } finally {
                logger.trace('handleEvent | beginning to process responseMessage');
                var responseEvent = this.responseMessage.toEventData();
                logger.debug('handleEvent | response event created: ' + responseEvent.friendlyDisplay());

                var appendData = {
                    expectedVersion: -2,
                    events: [responseEvent]
                };

                logger.debug('handleEvent | event data created: ' + appendData);
                logger.trace('handleEvent | publishing notification');
                this.result = await eventstore.appendToStreamPromise('notification', appendData);
            }
            // largely for testing purposes, sadly
            return this.result;
        }