backend-nestjs

GitHub Actions 和 GitLab CI 的 CI/CD 管道最佳实践。适用于在搭建或修改 CI/CD 管道时使用。

SKILL.md

--- frontmatter

name: backend-nestjs
description: NestJS backend development conventions. Use when working on NestJS/Node.js TypeScript backend projects.

Backend NestJS Conventions

This skill provides specific conventions for NestJS backend development.

When to Use

•Use this skill when working on NestJS projects
•Use this skill when creating new NestJS modules, services, or controllers
•This skill builds upon project-standards skill

Instructions

1. Architecture

•Adhere to Modular Monolith architecture.
•Each Feature is a separate Module (AuthModule, UserModule).

2. Module Structure

code

src/
├── modules/
│   ├── auth/
│   │   ├── auth.module.ts
│   │   ├── auth.controller.ts
│   │   ├── auth.service.ts
│   │   ├── dto/
│   │   │   ├── login.dto.ts
│   │   │   └── register.dto.ts
│   │   ├── entities/
│   │   │   └── user.entity.ts
│   │   └── guards/
│   │       └── jwt.guard.ts

3. DTO (Data Transfer Object)

•MUST use class-validator to validate input.
•File naming: create-user.dto.ts, update-user.dto.ts.

typescript

import { IsEmail, IsString, MinLength } from 'class-validator';

export class CreateUserDto {
  @IsEmail()
  email: string;

  @IsString()
  @MinLength(8)
  password: string;
}

4. Services

•Business Logic MUST reside in the Service, not in the Controller.
•Define Interfaces for Services to facilitate Mock testing.

typescript

// user.service.interface.ts
export interface IUserService {
  findById(id: string): Promise<User>;
  create(dto: CreateUserDto): Promise<User>;
}

// user.service.ts
@Injectable()
export class UserService implements IUserService {
  constructor(
    @InjectRepository(User)
    private readonly userRepository: Repository<User>,
  ) {}
}

5. Controllers

•Controllers should be thin - only handle HTTP concerns.
•Use appropriate decorators for routes.

typescript

@Controller('users')
export class UserController {
  constructor(private readonly userService: UserService) {}

  @Get(':id')
  async findOne(@Param('id') id: string): Promise<User> {
    return this.userService.findById(id);
  }

  @Post()
  @HttpCode(HttpStatus.CREATED)
  async create(@Body() dto: CreateUserDto): Promise<User> {
    return this.userService.create(dto);
  }
}

6. Exception Handling

•Use NestJS built-in exceptions (NotFoundException, BadRequestException).
•Create custom exceptions for domain-specific errors.

typescript

throw new NotFoundException(`User with ID ${id} not found`);
throw new BadRequestException('Invalid email format');

7. Dependency Injection

•Always use constructor injection.
•Register providers in the module's providers array.

8. Configuration

•Use @nestjs/config for environment variables.
•Never hardcode secrets or URLs.

9. Testing

•Unit tests for Services (mock repositories).
•E2E tests for Controllers (test HTTP layer).