[Solved] Why does this guard fail to read metadata?const roles = this.reflector.get('roles', context.getClass());Given that the metadata was set on the method using @SetMetadata('roles', ['admin']). | NestJS

NestJS - Guards

Why does this guard fail to read metadata?

const roles = this.reflector.get('roles', context.getClass());

Given that the metadata was set on the method using @SetMetadata('roles', ['admin']).

ABecause metadata was set on the method, but get is called on the class

BBecause the key 'roles' is misspelled

CBecause Reflector.get requires a third argument

DBecause context.getClass() returns undefined

Step-by-Step Solution

Solution:

Step 1: Understand metadata scope
Metadata set on a method is not available on the class level, so calling get with context.getClass() returns undefined.
Step 2: Check other options
The key is correct, Reflector.get does not require a third argument, and context.getClass() returns the class.
Final Answer:
Because metadata was set on the method, but get is called on the class -> Option A
Quick Check:
Metadata scope must match get target = B [OK]

Quick Trick: Match metadata set location with Reflector.get target [OK]

Common Mistakes:

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Why does this guard fail to read metadata?