pos-system/services/ads-serving-service-net/docs/vi/ARCHITECTURE.md

Ads Serving Service Architecture

Tổng Quan / Overview

graph LR
    subgraph "Request Flow < 100ms"
        REQ[Ad Request] --> GW[Traefik Gateway]
        GW --> CACHE[Redis Cache]
        CACHE --> AUC[Auction Engine]
        AUC --> RESP[Response]
        RESP --> EVT[Fire Events Async]
    end
    
    subgraph "Async Events"
        EVT --> MQ[RabbitMQ]
        MQ --> BILL[ads-billing]
        MQ --> TRACK[ads-tracking]
        MQ --> ANAL[ads-analytics]
    end

Domain Aggregates

AdRequest Aggregate

• AdRequest: Placement, UserContext, Device

Auction Aggregate

• Auction (Root): Single ad auction instance
• Bid: Candidate ad with calculated score
• AuctionResult: Winner, final price

Pacing Aggregate

• BudgetPacer: Smooth/Accelerated spending
• SpendTracker: Real-time budget consumption

Frequency Aggregate

• FrequencyCap: Max impressions per user/day
• UserAdHistory: Redis-backed view tracking

eCPM Calculation

eCPM = (Bid × Predicted_CTR × 1000) + Quality_Score

Where:
- Bid: Advertiser's bid amount
- Predicted_CTR: ML-predicted click probability
- Quality_Score: Ad relevance + landing page quality

Redis Data Structures

Key	Type	TTL	Purpose
ads:active:{placement}	Sorted Set	5 min	Active ads by eCPM
freq:{userId}:{date}	Hash	24h	Ad views per user
budget:{campaignId}:{date}	String	24h	Daily spend counter
target:{criteria}	Set	1h	Eligible ad sets

Latency Budget

Phase	Target
Redis lookup	< 5ms
Auction logic	< 20ms
Response serialization	< 5ms
Total	< 100ms