SOLID Principles in JavaScript

Which SOLID principle suggests that abstractions should not depend on details?

// Before:
class UserService {
  constructor() {
    this.repository = new MySQLRepository();
    this.logger = new FileLogger();
  }
}

// After:
class UserService {
  constructor(
    private repository: Repository,
    private logger: Logger
  ) {}
}

Single Responsibility Principle
Open/Closed Principle
Dependency Inversion Principle
This example demonstrates the Dependency Inversion Principle (DIP). In the 'Before' version, UserService directly depends on concrete implementations (MySQLRepository and FileLogger). The 'After' version depends on abstractions (Repository and Logger interfaces) instead. This makes the code more flexible, testable, and maintainable as different implementations can be injected without changing UserService.
Interface Segregation Principle

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