Explicit Validation
Explicit validation is a software development practice where validation logic is clearly and directly defined in code, often using dedicated validation libraries or frameworks to check input data against specific rules. It involves writing explicit checks for data integrity, such as verifying required fields, data types, ranges, or custom business rules, typically at the boundaries of an application (e.g., API endpoints or user interfaces). This approach contrasts with implicit validation, where validation might be inferred or handled automatically by underlying systems.
Developers should use explicit validation to ensure data quality, security, and reliability in applications, particularly in scenarios like web forms, API requests, or data processing pipelines where user input or external data must be sanitized. It helps prevent common vulnerabilities like injection attacks, improves error handling by providing clear feedback, and aligns with practices such as defensive programming and domain-driven design to enforce business constraints explicitly.