Body

Kind: Function

Source: packages/common/decorators/http/route-params.decorator.ts

Part of: Common

Route handler parameter decorator. Extracts the entire body object property, or optionally a named property of the body object, from the req object and populates the decorated parameter with that value. Also applies pipes to the bound body parameter.

For example:

typescript
async create(@Body('role', new ValidationPipe()) role: string)

Body() binds a route handler parameter to the request body value. When given a property key, it extracts that property from req.body; pipes passed to the decorator run on the bound value.

Signature

ts
function Body(property: string | (Type<PipeTransform> | PipeTransform), pipes: (Type<PipeTransform> | PipeTransform)[]): ParameterDecorator

Parameters

Returns: ParameterDecorator

Diagram

mermaid
graph LR
  Request[HTTP request] --> ReqBody[req.body]
  ReqBody --> BodyDecorator["@Body()"]
  BodyDecorator --> Property[Selected body property]
  Property --> Pipes[Pipes]
  Pipes --> Parameter[Route handler parameter]

Usage

typescript
import { Body, Controller, Post, ValidationPipe } from '@nestjs/common';

@Controller('users')
export class UsersController {
  @Post()
  async create(
    @Body('role', new ValidationPipe()) role: string,
  ) {
    return { role };
  }
}

AI Coding Instructions

• Use @Body() when the handler needs the full request body.
• Pass a property key, such as @Body('role'), when the handler needs a single body field.
• Pass pipes after the property key so they receive the extracted value.
• Keep body-property names aligned with the request DTO or client payload.