102. Controllers

Controllers

• Controllers | NestJS - A progressive Node.js framework
• Nest.js controllers are responsible for handling HTTP requests and routing.
  • For instance: The users.controller.ts file would define the routes and associated request handlers for the users feature.

@Controller('users')
export class UsersController {
  constructor(private readonly usersService: UsersService) {}

  @Post()
  create(@Body() createUserDto: CreateUserDto) {
    return this.usersService.create(createUserDto);
  }

  @Get()
  findAll() {
    return this.usersService.findAll();
  }

  @Get(':id')
  findOne(@Param('id') id: string) {
    return this.usersService.findOne(+id);
  }

  @Patch(':id')
  update(@Param('id') id: string, @Body() updateUserDto: UpdateUserDto) {
    return this.usersService.update(+id, updateUserDto);
  }

  @Delete(':id')
  remove(@Param('id') id: string) {
    return this.usersService.remove(+id);
  }
}

• Finally you need to add your controller to the respective module

@Module({
  controllers: [CatsController],
})
export class AppModule {}

How to Change Response Status Code

• Controllers | NestJS - A progressive Node.js framework
• i.e by default 201 is returned from a post method
  • ans: use @HttpCode(status_code), decorator

  @Post()
  @HttpCode(HttpStatus.GONE)
  create(@Body() body) {
    return body;
  }

How to Gain Full Control of Req and Res

• Controllers | NestJS - A progressive Node.js framework
• use express, of fastify's, request and response arguments
• pros:
  • can let us fully control response and request, such as set header
• cons
  • not a standard way of doing things in next, might cause compatibility issue
  • harder to test better to use nest standard response

import { Controller, Get, Post, Res, HttpStatus } from '@nestjs/common';
import { Response } from 'express';

@Controller('cats')
export class CatsController {
  @Post()
  create(@Res() res: Response) {
    res.status(HttpStatus.CREATED).send();
  }

  @Get()
  findAll(@Res() res: Response) {
     res.status(HttpStatus.OK).json([]);
  }
}