VIPER

VIPER

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Definition

VIPER is an architecture pattern that separates application into five distinct components: View, Interactor, Presenter, Entity, and Router. It originated from Clean Architecture principles and is commonly used in iOS development.

flowchart TB
    subgraph View
        V[View]
    end
    subgraph Presenter
        P[Presenter]
    end
    subgraph Interactor
        I[Interactor]
    end
    subgraph Entity
        E[Entity]
    end
    subgraph Router
        R[Router]
    end
    
    V <-->|user actions| P
    P <-->|presentation data| I
    I <-->|business logic| E
    P <-->|navigation| R
    R -->|creates| V

Flow

  1. View receives user input and forwards to Presenter
  2. Presenter formats user actions and requests data from Interactor
  3. Interactor performs business logic using Entity objects
  4. Interactor returns result to Presenter
  5. Presenter formats data and updates View
  6. Router handles navigation between scenes/modules

Component Responsibilities

View

  • Displays data to user
  • Receives user input
  • Delegates user actions to Presenter
  • Passive (no business logic)

Interactor

  • Contains business logic
  • Fetches and manipulates data from Entities
  • Independent of UI
  • Highly testable

Presenter

  • Formats data for View display
  • Receives View actions and routes to Interactor
  • Handles presentation logic
  • Coordinates View and Interactor

Entity

  • Basic model objects
  • Data structures
  • No business logic
  • Used by Interactor

Router (Wireframe)

  • Handles navigation between modules
  • Creates new VIPER modules
  • Manages navigation stack
  • Handles deep linking

Key Characteristics

  • Strict Separation: Each component has single responsibility
  • Testability: Every component can be unit tested independently
  • Modularity: Each feature is self-contained VIPER module
  • Scalability: Easy to add new features without affecting existing code

Common Implementations

  • iOS: VIPER is widely adopted in iOS development
  • Used with SwiftUI and UIKit
  • Often combined with Clean Architecture

NOTE

VIPER can be verbose for simple features. Consider project complexity before adopting.

Components

Recent Notes

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