Blog service with DDD and Layered Architecture

This is a sample project demonstrating the implementation of a blog service using Domain-Driven Design (DDD) and Layered Architecture principles.

Directory Structure

src/

• interface/: Interface Layer

  • controllers: HTTP Request Handling
  • middlewares: Middleware Functions
  • routes: Route Definitions

• application/: Application Layer

  • services: Application Services
  • commands: Command Objects
  • errors: Custom Error Classes

• domain/: Domain Layer

  • models: Entities and Value Objects
  • services: Domain Services
  • repositories: Repository Interface Definitions

• infrastructure/: Infrastructure Layer

  • prisma: Prisma Related Configurations
  • repositories: Concrete Repository Implementations

tests/

• unit: Unit Tests
• helpers: Test Helper Functions

Dependency Direction

interface → application → domain ← infrastructure

Technical Stack

• Docker
• TypeScript
• Node.js
• Express
• Prisma
• SQLite
• Vitest
• ESLint
• Prettier
• GitHub Actions (CI)

How to run

1. docker compose up app-dev -d
2. docker compose exec app-dev npm run prisma:migrate-dev

How to test

1. docker compose exec app-dev npm run test
2. docker compose exec app-dev npm run test:coverage

Example API requests

1. Create a new user

curl -X POST http://localhost:3000/api/users \
  -H "Content-Type: application/json" \
  -d '{
    "name": "John Doe",
    "email": "john@example.com"
  }'

Expected response (201 Created)

{
  "id": 1,
  "name": "John Doe",
  "email": "john@example.com"
}

2. Get user by ID

curl -X GET http://localhost:3000/api/users/1

Expected response (200 OK)

{
  "id": 1,
  "name": "John Doe",
  "email": "john@example.com"
}

3. Create a new article

curl -X POST http://localhost:3000/api/articles \
  -H "Content-Type: application/json" \
  -d '{
    "title": "My First Article",
    "content": "This is the content of my first article.",
    "userId": 1
  }'

Expected response (201 Created)

{
  "id": 1,
  "title": "My First Article",
  "content": "This is the content of my first article.",
  "userId": 1,
  "createdAt": "2024-12-24T10:00:00.000Z"
}

4. Get article by ID

curl -X GET http://localhost:3000/api/articles/1

Expected response (200 OK)

{
  "id": 1,
  "title": "My First Article",
  "content": "This is the content of my first article.",
  "userId": 1,
  "createdAt": "2024-12-24T10:00:00.000Z"
}

5. Get user's articles

curl -X GET http://localhost:3000/api/users/1/articles

Expected response (200 OK)

[
  {
    "id": 1,
    "title": "My First Article",
    "content": "This is the content of my first article.",
    "userId": 1,
    "createdAt": "2024-12-24T10:00:00.000Z"
  }
]

6. Delete article (by owner)

curl -X DELETE http://localhost:3000/api/articles/1/users/1

Expected response (204 No Content)

7. Delete user

curl -X DELETE http://localhost:3000/api/users/1

Expected response (204 No Content)

Example requests with error responses

8. Create user with duplicate email

curl -X POST http://localhost:3000/api/users \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Jane Doe",
    "email": "john@example.com"
  }'

Expected response (409 Conflict)

9. Create article with invalid user

curl -X POST http://localhost:3000/api/articles \
  -H "Content-Type: application/json" \
  -d '{
    "title": "Invalid Article",
    "content": "This article should not be created.",
    "userId": 999
  }'

Expected response (404 Not Found)

10. Delete article by non-owner

curl -X DELETE http://localhost:3000/api/articles/1/users/2

Expected response (403 Forbidden)