Search Service

Overview

The Search Service provides product search functionality using OpenSearch. It receives product change events from Product Catalog through Kafka to automatically synchronize the search index. In Secondary regions, data is synchronized through DocumentDB change streams.

Item	Details
Language	Go 1.21+
Framework	Gin
Database	OpenSearch, DocumentDB (Change Stream)
Cache	ElastiCache (Valkey)
Namespace	core-services
Port	8080
Health Check	/healthz, /readyz

Architecture

Key Features

1. Product Search

• Multi-field search (name, description, SKU)
• Category filtering
• Price range filtering
• Pagination

2. Search Result Caching

• Search result caching via Valkey (5-minute TTL)
• Duplicate query prevention based on cache keys

3. Real-time Index Synchronization

• Index updates via Kafka events
• Secondary region synchronization through DocumentDB Change Stream

API Endpoints

Product Search

Method	Path	Description
GET	/api/v1/search	Product search

Request Parameters

Parameter	Type	Required	Description	Default
q	string	N	Search keyword	-
category	string	N	Category ID	-
min_price	float	N	Minimum price	-
max_price	float	N	Maximum price	-
page	int	N	Page number	1
size	int	N	Page size (max 100)	20

Request Example

GET /api/v1/search?q=laptop&category=electronics&min_price=500000&max_price=2000000&page=1&size=20

Response Example

{
  "products": [
    {
      "id": "prod-001",
      "name": "Samsung Galaxy Book Pro",
      "description": "15.6-inch AMOLED display laptop",
      "sku": "SGB-PRO-15",
      "price": 1590000,
      "currency": "KRW",
      "category_id": "electronics",
      "images": [
        "https://cdn.example.com/products/sgb-pro-1.jpg"
      ],
      "attributes": {
        "brand": "Samsung",
        "display_size": "15.6",
        "memory": "16GB"
      },
      "is_active": true
    }
  ],
  "total": 42,
  "page": 1,
  "size": 20
}

Data Models

Product (Search Index)

type Product struct {
    ID          string            `json:"id"`
    Name        string            `json:"name"`
    Description string            `json:"description"`
    SKU         string            `json:"sku"`
    Price       float64           `json:"price"`
    Currency    string            `json:"currency"`
    CategoryID  string            `json:"category_id"`
    Images      []string          `json:"images"`
    Attributes  map[string]string `json:"attributes"`
    IsActive    bool              `json:"is_active"`
}

SearchParams

type SearchParams struct {
    Query    string   // Search keyword
    Category string   // Category filter
    MinPrice *float64 // Minimum price
    MaxPrice *float64 // Maximum price
    Page     int      // Page number
    Size     int      // Page size
}

SearchResult

type SearchResult struct {
    Products []Product `json:"products"`
    Total    int64     `json:"total"`
    Page     int       `json:"page"`
    Size     int       `json:"size"`
}

OpenSearch Index Mapping

{
  "mappings": {
    "properties": {
      "id": {"type": "keyword"},
      "name": {"type": "text", "analyzer": "standard"},
      "description": {"type": "text", "analyzer": "standard"},
      "sku": {"type": "keyword"},
      "price": {"type": "float"},
      "currency": {"type": "keyword"},
      "category_id": {"type": "keyword"},
      "is_active": {"type": "boolean"}
    }
  }
}

Events (Kafka)

Subscribed Topics

Topic	Description	Consumer Group
catalog.product.created	Product creation event	search-indexer
catalog.product.updated	Product update event	search-indexer
catalog.product.deleted	Product deletion event	search-indexer

Event Payload Examples

product.created / product.updated

{
  "event": "product.created",
  "product": {
    "id": "prod-001",
    "name": "Samsung Galaxy Book Pro",
    "description": "15.6-inch AMOLED display laptop",
    "sku": "SGB-PRO-15",
    "price": 1590000,
    "currency": "KRW",
    "category_id": "electronics",
    "images": ["https://cdn.example.com/products/sgb-pro-1.jpg"],
    "attributes": {"brand": "Samsung"},
    "is_active": true
  }
}

product.deleted

{
  "event": "product.deleted",
  "product_id": "prod-001"
}

Environment Variables

Variable	Description	Default
PORT	Server port	8080
AWS_REGION	AWS region	us-east-1
REGION_ROLE	Region role (PRIMARY/SECONDARY)	PRIMARY
OPENSEARCH_ENDPOINT	OpenSearch endpoint	http://localhost:9200
CACHE_HOST	ElastiCache host	localhost
CACHE_PORT	ElastiCache port	6379
KAFKA_BROKERS	Kafka broker address	localhost:9092
DOCUMENTDB_HOST	DocumentDB host (Secondary)	localhost
DOCUMENTDB_PORT	DocumentDB port	27017
LOG_LEVEL	Log level	info

Service Dependencies

Services It Depends On

Service	Purpose
OpenSearch	Search index storage and queries
ElastiCache (Valkey)	Search result caching
MSK (Kafka)	Product change event reception
DocumentDB	Change Stream (Secondary region)

Components That Depend On This Service

Component	Purpose
API Gateway	Search API routing
Web/Mobile clients	Product search

Multi-Region Behavior

Primary Region (us-east-1)

• Receives Product Catalog changes via Kafka events
• Updates OpenSearch index

Secondary Region (us-west-2)

• Dual synchronization via Kafka events + DocumentDB Change Stream
• Detects replicated data from DocumentDB Global Cluster via Change Stream
• Updates local OpenSearch index

Caching Strategy

Search results are cached in Valkey for 5 minutes.

Cache Key Format

search:{query}:{category}:{page}:{size}[:min{price}][:max{price}]

Example:

search:laptop:electronics:1:20:min500000:max2000000