[Solved] Identify the error in this NestJS guard code for role checking: canActivate(context: ExecutionContext): boolean { const request = context.switchToHttp().getRequest(); const user = request.user;... | NestJS

NestJS - Authentication

Identify the error in this NestJS guard code for role checking:

canActivate(context: ExecutionContext): boolean {
  const request = context.switchToHttp().getRequest();
  const user = request.user;
  const roles = this.reflector.get('roles', context.getHandler());
  if (!roles) {
    return true;
  }
  return roles.includes(user.role);
}

AMissing async keyword on canActivate

BReturning true when roles are not defined

CUsing getHandler() instead of getClass() for roles

DNot checking if user exists before accessing user.role

Step-by-Step Solution

Solution:

Step 1: Review user role access
The code accesses user.role without verifying if user is defined.
Step 2: Identify potential runtime error
If user is undefined, accessing user.role causes an error.
Final Answer:
Not checking if user exists before accessing user.role -> Option D
Quick Check:
Always check user before role access [OK]

Quick Trick: Check user object exists before role check [OK]

Common Mistakes:

Assuming user is always present
Confusing getHandler() and getClass() usage
Thinking async is required for synchronous guard

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More NestJS Quizzes

Identify the error in this NestJS guard code for role checking:

Step 1: Review user role access

Step 2: Identify potential runtime error

Final Answer:

Quick Check:

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