NestJS Guards and Interceptors

Master NestJS guards and interceptors for implementing authentication, authorization, logging, and request/response transformation.

Guards Fundamentals

Understanding CanActivate and ExecutionContext.

import { Injectable, CanActivate, ExecutionContext } from '@nestjs/common';
import { Observable } from 'rxjs';

@Injectable()
export class BasicGuard implements CanActivate {
  canActivate(
    context: ExecutionContext,
  ): boolean | Promise<boolean> | Observable<boolean> {
    const request = context.switchToHttp().getRequest();