NestExpressBodyParserType

Kind: Type

Source: packages/platform-express/interfaces/nest-express-body-parser.interface.ts

Part of: Platform Express

Interface defining possible body parser types, to be used with NestExpressApplication.useBodyParser().

NestExpressBodyParserType defines the supported body parser names accepted by NestExpressApplication.useBodyParser(). It lets Express-based Nest applications configure how incoming request bodies are parsed, including JSON, URL-encoded form data, raw buffers, and plain text.

Definition

ts
'json' | 'urlencoded' | 'text' | 'raw'

Diagram

mermaid
graph LR
  A[Incoming HTTP Request] --> B[NestExpressApplication.useBodyParser]
  B --> C{NestExpressBodyParserType}
  C --> D[json]
  C --> E[urlencoded]
  C --> F[raw]
  C --> G[text]
  D --> H[Parsed request body]
  E --> H
  F --> H
  G --> H

Usage

ts
import { NestFactory } from '@nestjs/core';
import { AppModule } from './app.module';
import type { NestExpressApplication } from '@nestjs/platform-express';

async function bootstrap() {
  const app = await NestFactory.create<NestExpressApplication>(AppModule);

  const parserType: 'json' = 'json';

  app.useBodyParser(parserType, {
    limit: '10mb',
  });

  await app.listen(3000);
}

bootstrap();

AI Coding Instructions

• Use this type only with NestExpressApplication.useBodyParser() in applications running on the Express platform.
• Choose json for JSON APIs, urlencoded for HTML form submissions, raw for buffer-based payloads such as webhook signatures, and text for plain-text requests.
• Configure parsers before starting the application with app.listen() so request handling uses the intended parser configuration.
• Avoid registering conflicting body parsers for the same content type, especially when validating raw webhook payload signatures.
• Keep parser options compatible with Express/body-parser options, such as limit, type, and extended for URL-encoded payloads.