Wishlist Service

Overview

The Wishlist Service provides functionality for users to save and manage products they are interested in. Users can collect products they want to purchase later and receive notifications about price changes or restocking.

Item	Value
Language	Python 3.11
Framework	FastAPI
Database	DocumentDB (MongoDB compatible)
Namespace	mall-services
Port	8000
Health Check	GET /health

Architecture

API Endpoints

Wishlist API

Method	Path	Description
GET	/api/v1/wishlists/{user_id}	Get wishlist
POST	/api/v1/wishlists/{user_id}/items	Add item
DELETE	/api/v1/wishlists/{user_id}/items/{product_id}	Remove item

Request/Response Examples

Get Wishlist

Request:

GET /api/v1/wishlists/user_001

Response:

{
  "user_id": "user_001",
  "items": [
    {
      "product_id": "prod_001",
      "added_at": "2024-01-15T10:00:00Z",
      "note": "Want to buy as a birthday gift"
    },
    {
      "product_id": "prod_002",
      "added_at": "2024-01-14T15:30:00Z",
      "note": null
    }
  ],
  "created_at": "2024-01-01T00:00:00Z",
  "updated_at": "2024-01-15T10:00:00Z"
}

Add Item

Request:

POST /api/v1/wishlists/user_001/items
Content-Type: application/json

{
  "product_id": "prod_003",
  "note": "Planning to buy when on sale"
}

Response (201 Created):

{
  "product_id": "prod_003",
  "added_at": "2024-01-15T11:00:00Z",
  "note": "Planning to buy when on sale"
}

Remove Item

Request:

DELETE /api/v1/wishlists/user_001/items/prod_001

Response (204 No Content)

Data Models

Wishlist

class Wishlist(BaseModel):
    user_id: str
    items: list[WishlistItem] = []
    created_at: datetime
    updated_at: datetime

WishlistItem

class WishlistItem(BaseModel):
    product_id: str
    added_at: datetime
    note: Optional[str] = None  # User note

WishlistItemCreate

class WishlistItemCreate(BaseModel):
    product_id: str
    note: Optional[str] = None

MongoDB Collection Schema

// wishlists collection
{
  "_id": ObjectId("..."),
  "user_id": "user_001",
  "items": [
    {
      "product_id": "prod_001",
      "added_at": ISODate("2024-01-15T10:00:00Z"),
      "note": "Birthday gift"
    }
  ],
  "created_at": ISODate("2024-01-01T00:00:00Z"),
  "updated_at": ISODate("2024-01-15T10:00:00Z")
}

// Indexes
db.wishlists.createIndex({ "user_id": 1 }, { unique: true })
db.wishlists.createIndex({ "items.product_id": 1 })

Events (Kafka)

Published Topics

Topic	Event	Description
wishlists.item-added	Item added	Published when item is added to wishlist
wishlists.item-removed	Item removed	Published when item is removed from wishlist

Event Payload Example

wishlists.item-added:

{
  "event_type": "wishlist.item-added",
  "user_id": "user_001",
  "product_id": "prod_003",
  "timestamp": "2024-01-15T11:00:00Z"
}

Event Usage

• Notification Service: Send notifications for wishlisted product price drops/restocking
• Recommendation Service: Improve personalized recommendations based on wishlists
• Analytics Service: Analyze popular wishlisted products

Environment Variables

Variable	Description	Default
SERVICE_NAME	Service name	wishlist
PORT	Service port	8080
AWS_REGION	AWS region	us-east-1
REGION_ROLE	Region role (PRIMARY/SECONDARY)	PRIMARY
DB_HOST	Database host	localhost
DB_PORT	Database port	27017
DB_NAME	Database name	wishlists
DB_USER	Database user	mall
DB_PASSWORD	Database password	-
DOCUMENTDB_HOST	DocumentDB host	localhost
DOCUMENTDB_PORT	DocumentDB port	27017
KAFKA_BROKERS	Kafka broker address	localhost:9092
LOG_LEVEL	Log level	info

Service Dependencies

Services It Depends On

• DocumentDB: Wishlist data storage
• Product Catalog: Product existence validation (optional)

Services That Depend On This

• Notification Service: Wishlist product notifications
• Recommendation Service: User interest identification
• Analytics Service: Wishlist trend analysis

Feature Details

Wishlist Limits

• Maximum 100 products per user
• No duplicate products allowed
• Out-of-stock/deleted products retained (for notification purposes)

Notification Integration

Notifications triggered for the following events on wishlisted products:

• Price drop (10% or more)
• Restocking
• Low stock (5 or fewer items)