Skip to main content

AI Brief: hbf-event-publisher

A NestJS service that bridges platform events (livechat, survey, chat session) to external automation connectors (Microsoft Power Automate) and delivers push notifications to mobile/web devices via Firebase. It is the platform's outbound event bus.

What This Repo Does​

hbf-event-publisher exposes two API surfaces: a connectors API that registers, lists, triggers, and tracks external flows (e.g., Power Automate webhooks), and a push notifications API that registers device tokens and sends FCM messages to individual or multiple users. Trigger delivery is synchronous (direct HTTP).

Tech Stack​

  • Language: TypeScript
  • Framework: NestJS v9 (Express platform)
  • Key dependencies: @nestjs/typeorm, typeorm, mysql2, cache-manager, firebase-admin, @nestjs/jwt, got, nestjs-pino, elastic-apm-node

Entry Points​

  • Main: src/main.ts
  • Root module: src/app.module.ts
  • Config: .env / .env.local (loaded by @nestjs/config)

Key Directories​

DirectoryPurpose
src/services/connectors/Connector API: flow registration, trigger dispatch, status callback.
src/services/connectors/power-automate/Power Automate implementation of IConnectorsService.
src/services/push/Push notifications API: device registration, Firebase send.
src/services/push/firebase/Firebase Admin SDK implementation of IPushNotificationService.
src/services/clients/HTTP client wrappers for hbf-core.
src/services/auth/JWT signing/verification service.
src/entities/TypeORM entities: FlowAssociation, PushAssociation.
src/dtos/Request/response DTOs with class-validator.
src/guards/HBFGuard (hbf-core token), JWTGuard (internal JWT).
src/migrations/TypeORM database migrations.

API Surface​

Connectors (/connectors)​

  • GET /connectors/flows?triggerType=&organizationId=&tenantId=&activityId= — list registered flows
  • DELETE /connectors/flows/:flowId — delete a flow
  • POST /connectors/flows:trigger?triggerType=&organizationId=&tenantId=&activityId= — fire matching flows
  • PATCH /connectors/triggers/:flowId — callback to update trigger success/failure status

Push Notifications (/push/:implementation)​

  • POST /push/:implementation/register — register device token
  • POST /push/:implementation/unregister — invalidate device token
  • POST /push/:implementation/send — send to one platform user
  • POST /push/:implementation/send-to-many — send to multiple platform users
  • POST /push/:implementation/send-batch — send batch of messages to one user
  • POST /push/:implementation/send-batch-to-many — send batch to multiple users

Current implementation values: firebase.

Trigger Types (enum TriggerType)​

livechat-request-missed, livechat-conversation-finished, survey-completed, automated-answer-triggered, chat-session-completed

External Dependencies​

  • MySQL: TypeORM with MySQL2 driver — stores FlowAssociation and PushAssociation tables
  • Firebase Admin SDK: firebase-admin — FCM multicast push delivery (max 500 tokens/request)
  • hbf-core: validates inbound HBF tokens via HBFGuard
  • APM: elastic-apm-node — optional

Running Locally​

npm install
cp .env .env.local   # fill in DB credentials, Firebase key path, JWT secrets
npm run start:dev

Tests​

npm test          # unit tests (jest)
npm run test:e2e  # e2e tests
npm run test:cov  # coverage report