Notification Service

Multi-channel notification system for engaging learners across email, SMS, push, and in-app channels

Requirements Document

Comprehensive requirements for the Notification Service microservice in the KnowledgeTracker Platform.

1. Functional Requirements

1.1 Multi-Channel Notification Delivery

  • Support Email, SMS, Push Notifications (web and mobile), and In-App notifications
  • Channel priority and fallback mechanisms (e.g., if push fails, send email)
  • User preferences for notification channels and frequency
  • Opt-in/opt-out management per channel and notification type

1.2 Notification Templates

  • Template creation with dynamic variables (user name, course name, etc.)
  • Multi-language template support with localization
  • Rich text formatting for email and in-app notifications
  • Template versioning and A/B testing capabilities
  • Organization-level template customization (branding, colors, logos)

1.3 Scheduled & Triggered Notifications

  • Event-triggered notifications (course enrollment, assignment due, grade posted)
  • Scheduled notifications (daily digests, weekly summaries, reminders)
  • Recurring notification patterns (daily, weekly, monthly)
  • Time-based triggers (send reminder 24 hours before deadline)
  • Timezone-aware delivery based on user location

1.4 Notification Management

  • In-app notification center with read/unread status
  • Mark as read, archive, delete functionality
  • Notification history and audit trail
  • Batch notification sending for announcements
  • Notification grouping and threading

1.5 Delivery Tracking & Analytics

  • Track delivery status (sent, delivered, failed, bounced)
  • Open rate and click-through rate tracking for emails
  • Engagement metrics per notification type and channel
  • Retry mechanism for failed notifications
  • Bounce handling and email validation

1.6 Multi-Tenant Support

  • Organization-level notification settings and preferences
  • Custom SMTP/email gateway per organization
  • White-label notification templates with organization branding
  • Organization-specific notification quotas and rate limits

2. Non-Functional Requirements

2.1 Performance

  • Process up to 10,000 notifications per minute
  • Queue-based asynchronous processing for high volume
  • Notification delivery latency < 30 seconds for time-critical alerts

2.2 Scalability

  • Horizontal scaling to handle millions of notifications per day
  • Support for multiple notification workers/processors
  • Auto-scaling based on queue length and processing load

2.3 Reliability

  • 99.9% notification delivery success rate
  • Automatic retry mechanism with exponential backoff
  • Dead letter queue for permanently failed notifications
  • Idempotent notification processing (no duplicate sends)

2.4 Security

  • Encrypted notification content in transit and at rest
  • Email authentication (SPF, DKIM, DMARC)
  • API key/token authentication for external integrations
  • Rate limiting to prevent notification spam

3. Integration Requirements

3.1 Internal Microservices

  • User Management: Retrieve user contact information and preferences
  • Course Management: Course enrollment, deadline notifications
  • Assessment Engine: Grade posted, feedback available notifications
  • Discussion Forum: New post, reply, mention notifications

3.2 External Services

  • Email Providers: SendGrid, AWS SES, Mailgun
  • SMS Providers: Twilio, AWS SNS, Vonage
  • Push Notifications: Firebase Cloud Messaging, Apple Push Notification Service

Requirements Validation

Use this requirements document alongside the Database Design to validate:

  • All notification types are properly modeled in the database schema
  • User preferences and channel settings have corresponding tables/columns
  • Template management and versioning are supported
  • Delivery tracking and analytics can be captured
  • Multi-tenant isolation is properly implemented