控制器上可以启用拦截器，方法里面也可以；还可以全局启用，待会把控制器的去掉

src/app.module.ts

@@ -5,6 +5,8 @@ import { PostsModule } from './modules/posts/posts.module';
 import { DemoMiddleware } from './core/middleware/demo.middleware'
 import { APP_GUARD } from '@nestjs/core';
 import { DemoRolesGuard } from './core/guards/demo-roles.guard'
+import { APP_INTERCEPTOR } from '@nestjs/core';
+import { LoggingInterceptor } from './core/interceptors/logging.interceptor'
 
 
 
@@ -16,6 +18,10 @@ import { DemoRolesGuard } from './core/guards/demo-roles.guard'
     {
       provide: APP_GUARD,
       useClass: DemoRolesGuard,
+    },
+    {
+      provide: APP_INTERCEPTOR,
+      useClass: LoggingInterceptor,
     }
   ],
 })

src/core/interceptors/logging.interceptor.ts

@@ -4,6 +4,8 @@ import { Observable } from 'rxjs';
 @Injectable()
 export class LoggingInterceptor implements NestInterceptor {
   intercept(context: ExecutionContext, next: CallHandler): Observable<any> {
+    console.log('I am a interceptor!')
+    
     return next.handle();
   }
 }

src/modules/posts/posts.controller.ts

@@ -1,13 +1,15 @@
-import { Controller, Get, Post, Req, Query, Headers, Param, Body, HttpException, HttpStatus, ForbiddenException, UseFilters, UsePipes, ValidationPipe, ParseIntPipe, UseGuards, SetMetadata } from '@nestjs/common';
+import { Controller, Get, Post, Req, Query, Headers, Param, Body, HttpException, HttpStatus, ForbiddenException, UseFilters, UsePipes, ValidationPipe, ParseIntPipe, UseGuards, SetMetadata, UseInterceptors } from '@nestjs/common';
 import { CreatePostDto } from './post.dto';
 import { DemoService } from './providers/demo/demo.service'
 import { DemoFilter } from '../../core/filters/demo.filter'
 import { DemoAuthGuard } from '../../core/guards/demo-auth.guard'
 import { Roles } from '../../core/decorators/roles.decorator'
+import { LoggingInterceptor } from '../../core/interceptors/logging.interceptor'
 
 @Controller('posts')
 // @UseGuards(DemoAuthGuard)
 // @UseFilters(DemoFilter)
+@ UseInterceptors(LoggingInterceptor)
 export class PostsController {
 
     constructor(private readonly demoService: DemoService) {}