@nestgate/core

Core utilities and composable decorators for NestJS applications.

📦 Installation

npm install @nestgate/core
# or
pnpm add @nestgate/core
# or
yarn add @nestgate/core

🎯 Features

• Mix - Combine multiple classes with proper TypeScript types and metadata
• ConnectOne - Connect single nested entity with validation
• ConnectMany - Connect array of nested entities with validation

📚 API Reference

Mix

Combine multiple classes into one, inheriting all properties and decorators.

import { Mix } from '@nestgate/core';

class Timestamped {
  @DateTime()
  createdAt: Date;

  @DateTime()
  updatedAt: Date;
}

class SoftDelete {
  @DateTime({ required: false })
  deletedAt?: Date;

  @Boolean({ default: false })
  isDeleted: boolean;
}

// Combine multiple mixins
class User extends Mix(Timestamped, SoftDelete) {
  @UUID()
  id: string;

  @String()
  name: string;
}

Features:

• ✅ Full TypeScript type inference
• ✅ Swagger metadata preserved
• ✅ Validation decorators work correctly
• ✅ Multiple mixins supported

ConnectOne

Connect a single nested entity with automatic validation and transformation.

import { ConnectOne } from '@nestgate/core';

class Address {
  @String()
  street: string;

  @String()
  city: string;

  @String()
  country: string;
}

class User {
  @UUID()
  id: string;

  @String()
  name: string;

  // Single nested object
  @ConnectOne(Address, {
    description: 'User address',
    required: false,
  })
  address?: Address;
}

Options:

interface ConnectOptions {
  required?: boolean; // Default: true
  description?: string; // Swagger description
  example?: any; // Swagger example
  deprecated?: boolean; // Mark as deprecated
  exclude?: boolean; // Exclude from API response
}

Features:

• ✅ Automatic nested validation with @ValidateNested()
• ✅ JSON to class transformation with @Type()
• ✅ Swagger schema generation
• ✅ Optional/Required support

ConnectMany

Connect an array of nested entities.

import { ConnectMany } from '@nestgate/core';

class Post {
  @UUID()
  id: string;

  @String()
  title: string;

  @String()
  content: string;
}

class User {
  @UUID()
  id: string;

  @String()
  name: string;

  // Array of nested objects
  @ConnectMany(Post, {
    description: 'User posts',
    required: false,
  })
  posts?: Post[];
}

Features:

• ✅ Validates each array item
• ✅ Transforms each item to class instance
• ✅ Swagger shows array type correctly
• ✅ Works with pagination

💡 Examples

Complete CRUD Entity

import { Mix, ConnectOne, ConnectMany } from '@nestgate/core';

// Base mixins
class Timestamped {
  @DateTime()
  createdAt: Date;

  @DateTime()
  updatedAt: Date;
}

class Authorable {
  @UUID()
  authorId: string;
}

// Related entities
class Tag {
  @String()
  name: string;
}

class Comment {
  @String()
  text: string;

  @DateTime()
  createdAt: Date;
}

// Main entity with everything
class BlogPost extends Mix(Timestamped, Authorable) {
  @UUID()
  id: string;

  @String({ minLength: 3, maxLength: 200 })
  title: string;

  @String()
  content: string;

  @ConnectMany(Tag)
  tags: Tag[];

  @ConnectMany(Comment, { required: false })
  comments?: Comment[];
}

Multi-level Nesting

class Author {
  @UUID()
  id: string;

  @String()
  name: string;
}

class Comment {
  @String()
  text: string;

  @ConnectOne(Author)
  author: Author;
}

class Post {
  @String()
  title: string;

  @ConnectOne(Author)
  author: Author;

  @ConnectMany(Comment)
  comments: Comment[];
}

Excluding from Response

class User {
  @UUID()
  id: string;

  @String()
  email: string;

  // This won't appear in API response
  @ConnectOne(UserSettings, { exclude: true })
  internalSettings: UserSettings;
}

🔗 Related Packages

• @nestgate/rest - REST API decorators
• @nestgate/entity - Entity validation decorators
• @nestgate/setup - Quick application setup

📝 License

MIT © NestGate

🤝 Contributing

Contributions are welcome! Please see our Contributing Guide.

💬 Support

• Documentation
• GitHub Issues
• Discord