type_layer_rules

Purpose and Scope

• Type layer contains TypeScript definitions for frontend/types/**/*.ts
• Responsibilities: Define type-safe interfaces, API types, reusable utilities, ensure consistency
• MANDATORY: All types must be exported and use TypeScript

Type Organization

• types/auth.ts - Authentication-related types
• types/chat.ts - Chat and conversation types
• types/config.ts - Configuration types
• types/api.ts - API-related types
• Use descriptive names matching the domain they represent

Type Definition Standards

• Use interfaces for object shapes and API contracts
• Use type aliases for unions, primitives, and computed types
• Use enums for fixed sets of string/number values
• Use generic types for reusable type patterns
• Export all types for use in other modules

API Type Definitions

• Define separate interfaces for request and response data
• Use consistent naming conventions (e.g., UserRequest, UserResponse)
• Include optional fields with proper typing
• Use union types for status fields and enums
• Provide JSDoc comments for complex types

Component Props Types

• Define interfaces for all component props
• Use descriptive property names
• Include proper optional/required field indicators
• Use generic types for reusable component patterns
• Export types for use in component files
• CRITICAL: All logging must use logger.ts - never use console.log

Utility Types

• Create utility types for common patterns
• Use mapped types for transformations
• Implement conditional types for complex logic
• Provide type guards for runtime validation

Example

// frontend/types/auth.ts
export interface User {
  id: string;
  email: string;
  name: string;
  avatar?: string;
  role: UserRole;
  createdAt: string;
  updatedAt: string;
}

// Utility types
export type UserUpdateData = Partial<Pick<User, 'name' | 'avatar'>>;
export type UserCreateData = Omit<User, 'id' | 'createdAt' | 'updatedAt'>;