[Solved] Why is it important that guards in NestJS return a boolean or a Promise? — Ans: Because NestJS uses the return value to decide if route execution proceeds | NestJS

NestJS - Authentication

Why is it important that guards in NestJS return a boolean or a Promise?

ABecause guards are only allowed to return synchronous values

BBecause guards must always return true to avoid errors

CBecause NestJS uses the return value to decide if route execution proceeds

DBecause returning other types causes the server to crash

Step-by-Step Solution

Solution:

Step 1: Understand guard return types
Guards return boolean or Promise to indicate allow or deny access.
Step 2: Explain why this matters
NestJS uses this return value to decide if the route handler should run or be blocked.
Final Answer:
Because NestJS uses the return value to decide if route execution proceeds -> Option C
Quick Check:
Guard return controls route access [OK]

Quick Trick: Return boolean or Promise in guards [OK]

Common Mistakes:

Master "Authentication" in NestJS

9 interactive learning modes - each teaches the same concept differently

More NestJS Quizzes

Why is it important that guards in NestJS return a boolean or a Promise?