Node.js · Middle · Question 33 of 75

Why validate request input on the server even if the front end already validates it?

1Front-end validation doesn't work in all browsers
✓Correct answer: Anyone can send requests directly, bypassing the UI; the server is the only trusted boundary
3Validation on the server makes responses smaller

Explanation

Validate types, lengths and formats with a schema library (Zod, JSON Schema, Valibot) at the API boundary, and reject unknown fields.

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