JPA Jooq Marriage

This module demonstrates the usage of both JPA and JOOQ in a Spring Boot application for managing blog posts with comments and tags.

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Technologies Used

• Spring Boot

• Spring Data JPA

• JOOQ

• PostgreSQL

• OpenAPI (Swagger)

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API Endpoints

Create Post

POST /api/users/{user_name}/posts/

Request Body:

{
  "title": "Sample Post",
  "content": "Post content here",
  "published": true,
  "publishedAt": "2024-01-20T10:00:00",
  "comments": [
    {
      "title": "Comment Title",
      "review": "Comment content",
      "published": true,
      "publishedAt": "2024-01-20T10:00:00"
    }
  ],
  "tags": [
    {
      "name": "tech",
      "description": "Technology related posts"
    }
  ]
}

Get Post

GET /api/users/{user_name}/posts/{title}

Response:

{
  "title": "Sample Post",
  "content": "Post content here",
  "published": true,
  "publishedAt": "2024-01-20T10:00:00",
  "author": "user_name",
  "createdAt": "2024-01-20T10:00:00",
  "comments": [
    {
      "title": "Comment Title",
      "content": "Comment content",
      "published": true,
      "publishedAt": "2024-01-20T10:00:00"
    }
  ],
  "tags": [
    {
      "name": "tech",
      "description": "Technology related posts"
    }
  ]
}

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Sequence Diagrams

Post Creation Flow (JPA)

sequenceDiagram
    participant Client
    participant PostController
    participant JPAPostService
    participant PostRepository
    participant Database

    Client->>PostController: POST /api/posts/users/{user_name}
    PostController->>JPAPostService: createPost(postRequest, userName)
    JPAPostService->>PostRepository: existsByTitleIgnoreCase(title)
    PostRepository->>Database: SELECT EXISTS(...)
    Database-->>PostRepository: result
    PostRepository-->>JPAPostService: boolean
    
    alt Post exists
        JPAPostService-->>PostController: throw PostAlreadyExistsException
        PostController-->>Client: 409 Conflict
    else Post doesn't exist
        JPAPostService->>PostRepository: save(post)
        PostRepository->>Database: INSERT
        Database-->>PostRepository: saved post
        PostRepository-->>JPAPostService: Post
        JPAPostService-->>PostController: void
        PostController-->>Client: 201 Created
    end

Post Retrieval Flow (JOOQ)

sequenceDiagram
    participant Client
    participant PostController
    participant JooqPostService
    participant DSLContext
    participant Database

    Client->>PostController: GET /api/posts/users/{user_name}/{title}
    PostController->>JooqPostService: fetchPostByUserNameAndTitle(userName, title)
    JooqPostService->>DSLContext: select(...).from(POSTS)
    DSLContext->>Database: SELECT with JOINs
    Database-->>DSLContext: Result
    
    alt Post found
        DSLContext-->>JooqPostService: Records
        JooqPostService-->>PostController: PostResponse
        PostController-->>Client: 200 OK with PostResponse
    else Post not found
        JooqPostService-->>PostController: throw PostNotFoundException
        PostController-->>Client: 404 Not Found
    end

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Validation Rules

• Post title: Required, max 255 characters

• Post content: Required, max 10000 characters

• Comment title: Required, max 255 characters

• Comment review: Required, max 10000 characters

• Tag name: Required, 1-50 characters, alphanumeric with hyphens and underscores

• Tag description: Optional, max 200 characters

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Format code

This project uses Spotless to maintain consistent code formatting. Run the following command to format all files:

./mvnw spotless:apply

Run tests

./mvnw clean verify

Run locally

Ensure you have Docker and Maven installed. Then:

1. Start the required PostgreSQL database:

docker-compose -f docker/docker-compose.yml up -d

1. Run the application with the local profile (uses local database):

./mvnw spring-boot:run -Dspring-boot.run.profiles=local

Using Testcontainers at Development Time

Testcontainers provides isolated, throwaway instances of the PostgreSQL database for testing. This allows you to run the application without setting up a local database.

There are two ways to run the application with Testcontainers:

You can run TestJpaJooqApplication.java from your IDE directly. Alternatively, use Maven:

./mvnw spring-boot:test-run

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Useful Links

• Swagger UI - API documentation and testing interface

• Actuator Endpoints - Application monitoring and management