Medium
Microsoft

Design a Role-Based Password Validator Object-Oriented Design Interview

Design an extensible validator that applies different password policies to regular users, administrators, and super administrators.

1. Problem Statement

Design a password validator with different requirements for regular users, administrators, and super administrators. The policy should be easy to extend when roles or rules change.

2. Live Coding Format

Work in the provided coding workspace while explaining your decisions to the live interviewer. Validation may use inline tests, examples, comments, or a verbal walkthrough.

3. Key Focus Areas

  • 1
    Policy and rule interfaces
  • 2
    Role-to-policy composition
  • 3
    Useful validation errors
  • 4
    Unicode and normalization
  • 5
    Unit and boundary testing

4. What Strong Candidates Should Demonstrate

  • Model password policies without a brittle role-by-role conditional tree.
  • Keep validation rules composable, explainable, and easy to test.
  • Avoid security regressions when policies evolve.

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Practice this problem in the live coding workspace while the interviewer probes your clarification, implementation, trade-offs, and validation.

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Core Concepts

Object-Oriented DesignValidationSecurityTesting

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