Incoming Event middleware

Introduction

The incoming-event-middleware is in charge of managing events, that is, activities for the end-to-end communication between aura-bot and channels.

Channels can send events to aura-bot to inform about any relevant event happening on their side.
In particular, aura-bridge sends an event to aura-bot, when the transformation from bot activity to WhatsApp message fails, that is handled by this middleware.

When aura-bot receives an event, this middleware prevents the execution of the rest of the middlewares by completing the request flow.

There are two types of events:

• Log type: the channel asks aura-bot to log certain information
• emptyResponse type: Event sent by the bot when no response activity is sent. Currently, it is internally used for aura-bot towards aura-bridge.

  export enum TypeEvent {
      /**
       * Log event
       */
      Log = 'log',
      /**
       * Directline empty response event (Event sent by the bot when no response activity is sent)
       */
      EmptyResponse = 'emptyResponse'
  }
  

This middleware is executed once the HTTP request arrives at the server to the POST /api/messages endpoint and the Direct Line authentication executed by the Adapter is successful.

It is a Turn middleware, so it is executed during turn initialization. It is only executed if the type of the activity is event. In this case, the middleware records the KPIs and updates the context.

The source code of this middleware is included in Aura Bot Platform middlewares - Github repository.

Incoming Event flow diagram

The incoming-event-middleware flowchart is included below: