AgentSkillsCN

nestjs-backend-development

借助 NestJS 构建可扩展的服务器端应用。无论是（1）新建 NestJS 应用，（2）创建模块、控制器与服务，（3）配置数据库集成（TypeORM），（4）实现自定义 JWT 身份认证与授权，还是（5）搭建 API 文档（Swagger），此技能皆能助您事半功倍。

SKILL.md
--- frontmatter
name: nestjs-backend-development
description: Build scalable server-side applications with NestJS. Use when (1) creating a new NestJS app, (2) creating Modules, Controllers, and Services, (3) setting up Database integration (TypeORM), (4) implementing Authentication/Authorization (Custom JWT), or (5) setting up API Documentation (Swagger).

NestJS Backend Development

Build efficient, scalable Node.js server-side applications with NestJS.

Tech Stack

  • •NestJS 10+ (Core Framework)
  • •TypeScript (Language)
  • •TypeORM (Database ORM)
  • •PostgreSQL (Recommended Database)
  • •JWT (Authentication)
  • •Swagger (API Documentation)
  • •Jest (Testing)
  • •Docker (Containerization)

Quick Start

1. Create Project

Generating a new project with strict mode enabled is recommended.

bash
npm i -g @nestjs/cli
nest new my-nest-app --strict
cd my-nest-app

For detailed project setup and configuration (ConfigModule, ValidationPipe), see setup-guide.md.

2. Generate Resource

Use the CLI to generate a complete CRUD resource (Module, Controller, Service, DTOs, Entities).

bash
nest g resource users

For understanding the project structure and architecture, see project-structure.md.

3. Setup Database (TypeORM)

Install TypeORM and configured it in app.module.ts.

bash
npm install --save @nestjs/typeorm typeorm pg

For complete database configuration and Entity patterns, see database.md.

Workflows

Implementing Authentication

  1. •Install JWT package: npm install @nestjs/jwt
  2. •Create AuthModule: Configure JwtModule with secrets.
  3. •Create AuthGuard: Implement CanActivate to verify tokens with JwtService.
  4. •Protect Routes: Use AuthGuard on controllers/routes.

See authentication.md for the complete implementation guide.

Creating a Robust API Endpoint

  1. •Define DTO: Create a class with validation decorators.
  2. •Create Controller Method: Use decorators (@Post, @Body) and types.
  3. •Implement Service Logic: Handle business logic and database interactions.
  4. •Add Swagger Docs: Use @ApiProperty on DTOs and @ApiOperation on controllers.

See dto-validation.md for validation patterns.

Reference Files

  • •setup-guide.md - CLI installation, project creation, main.ts bootstrapping, ConfigModule.
  • •project-structure.md - Modular architecture, folder structure, core components (Modules, Controllers, Services).
  • •database.md - TypeORM setup, Entity definition, Repository pattern, Transactions.
  • •authentication.md - Custom JWT Guard, JwtService, Auth guards, CurrentUser decorator.
  • •dto-validation.md - DTO creation, class-validator decorators, Pipes.

Best Practices

Architecture

  • •Modularization: specific features should be in their own modules (e.g., AuthModule, UsersModule).
  • •Dependency Injection: Always inject dependencies via constructors. Avoid hard-coding.
  • •Environment Variables: Never commit secrets. Use @nestjs/config and .env files.

Code Quality

  • •DTOs: Always use DTOs for input data validation. Do not use raw objects.
  • •Strict Mode: Use TypeScript strict mode.
  • •Async/Await: Use async/await for all asynchronous operations (DB calls).

API Design

  • •RESTful: Follow REST conventions (GET /users, POST /users, GET /users/:id).
  • •Status Codes: Return appropriate HTTP status codes (201 Created, 400 Bad Request, 404 Not Found).
  • •Documentation: Keep Swagger documentation up to date.