NestExpressApplication

Kind: Interface

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

Part of: Platform Express

Interface describing methods on NestExpressApplication.

NestExpressApplication extends Nest’s standard application contract with Express-specific configuration APIs. Use it when an application needs Express features such as template engines, static asset serving, custom body parsers, and Express locals.

Diagram

mermaid
graph LR
  A[NestFactory.create] --> B[NestExpressApplication]
  B --> C[Configure views]
  B --> D[Serve static assets]
  B --> E[Configure body parsers]
  B --> F[Set Express locals]
  B --> G[listen()]
  G --> H[Express HTTP server]

Usage

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

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

  app.setBaseViewsDir(join(__dirname, '..', 'views'));
  app.setViewEngine('hbs');

  app.setStaticAssets(join(__dirname, '..', 'public'));
  app.setLocal('appName', 'My Nest App');

  app.useBodyParser('json', { limit: '2mb' });

  await app.listen(3000);
}

bootstrap();

AI Coding Instructions

• Create the application with NestFactory.create<NestExpressApplication>() when Express-specific methods are required.
• Configure view directories and the template engine before starting the server with listen().
• Use setStaticAssets() for public files instead of implementing static-file routes manually.
• Prefer useBodyParser() when custom parser limits or parser options are needed; ensure the selected parser matches the incoming content type.
• Keep Express-specific configuration in the bootstrap layer so application modules remain transport-agnostic.

Relationships

• IMPORTS → HttpServer
• IMPORTS → INestApplication