Split strategies (equal, exact, percentage) in LLD - Architecture Diagram

System Overview - Split strategies (equal, exact, percentage)

This system manages how a total amount is divided among multiple recipients using different split strategies: equal, exact, and percentage. It ensures accurate distribution based on user input and handles validations to prevent errors.

Architecture Diagram

User
  |
  v
Load Balancer
  |
  v
API Gateway
  |
  v
Split Service
  |       |        |
  v       v        v
Equal   Exact   Percentage
Handler Handler Handler
  |       |        |
  v       v        v
Database (Split Records)
  |
  v
Cache (Recent Splits)

Components

User

client

Initiates split requests with chosen strategy and amounts

Load Balancer

load_balancer

Distributes incoming requests evenly to API Gateway instances

API Gateway

api_gateway

Routes requests to the Split Service and handles authentication

Split Service

service

Processes split requests and delegates to specific strategy handlers

Equal Handler

service_component

Calculates equal splits among recipients

Exact Handler

service_component

Processes splits with exact amounts per recipient

Percentage Handler

service_component

Calculates splits based on percentage values per recipient

Database (Split Records)

database

Stores split transaction records and user data

Cache (Recent Splits)

cache

Caches recent split results for faster retrieval

Request Flow - 11 Hops

User → Load Balancer

Load Balancer → API Gateway

API Gateway → Split Service

Split Service → Cache (Recent Splits)

Cache (Recent Splits) → Split Service

Split Service → Equal Handler / Exact Handler / Percentage Handler

Equal Handler / Exact Handler / Percentage Handler → Split Service

Split Service → Database (Split Records)

Split Service → Cache (Recent Splits)

Split Service → API Gateway

API Gateway → User

Failure Scenario

Component Fails:Database (Split Records)

Impact:New split transactions cannot be saved, risking data loss; reads may fallback to cache but may be stale

Mitigation:Use database replication and failover; cache serves recent splits temporarily; alert system triggers for manual intervention

Architecture Quiz - 3 Questions

Which component is responsible for deciding how to split the amount based on the strategy?

A API Gateway

B Split Service

C Load Balancer

D Cache

Design Principle

This architecture cleanly separates concerns by using dedicated handlers for each split strategy, enabling easy extension and maintenance. Caching improves performance by avoiding repeated calculations, and the use of load balancer and API gateway ensures scalability and security.