Analytics Service

Purpose

analytics-service exposes admin analytics APIs and maintains aggregate tables fed by Kafka events.

Responsibilities

• Provide dashboard metrics
• Provide revenue, order, book, and payment analytics
• Consume order and payment events
• Deduplicate events using processed_events

Dependencies

• Port: 8088
• Database: bookstore_analytics_db
• Kafka consumer
• Admin-only JWT-protected APIs

REST APIs

Method	Path	Auth	Description
GET	/analytics/dashboard	Admin	High-level dashboard summary
GET	/analytics/revenue	Admin	Revenue totals, optional from and to
GET	/analytics/revenue/daily	Admin	Daily revenue series
GET	/analytics/revenue/monthly	Admin	Monthly revenue series
GET	/analytics/orders	Admin	Order analytics
GET	/analytics/books	Admin	Book sales analytics
GET	/analytics/payments	Admin	Payment analytics

Kafka

Consumers

• order-created
• payment-completed
• payment-failed

Aggregate tables

• daily_metrics
• book_sales
• pending_order_items
• processed_events

Ingestion & deduplication

Aggregate schema

Deduplication

The service stores event keys like:

• order-created:{orderId}
• payment-completed:{orderId}
• payment-failed:{paymentId}

This prevents double-counting under at-least-once delivery.

Known gap

The checked-in payment-service publishes payment-success, not payment-completed. Until that is corrected, success-side payment analytics will not fully update from Kafka.