Spring Boot Test Container PostgreSQL

A demonstration project showcasing the integration of Spring Boot with Testcontainers for PostgreSQL database testing.

Overview

This project is a RESTful API for managing blog posts, built with Spring Boot and PostgreSQL. It demonstrates how to use Testcontainers for integration testing with a real PostgreSQL database.

Technologies Used

• Java 21 (with preview features)
• Spring Boot 3.5.0
• Spring Data JDBC
• Spring WebFlux (WebClient)
• PostgreSQL
• Testcontainers
• Docker & Docker Compose
• Maven
• Springdoc OpenAPI

Prerequisites

• Java 21 or higher
• Docker and Docker Compose
• Maven

Getting Started

Clone the Repository

git clone https://github.com/hendisantika/spring-boot-test-container-postgresql.git
cd spring-boot-test-container-postgresql

Build and Run

You can run the application using Maven:

./mvnw spring-boot:run

Or build and run the JAR file:

./mvnw clean package
java -jar target/test-container-postgresql-0.0.1-SNAPSHOT.jar

Using Docker Compose

The project includes a compose.yaml file for running the PostgreSQL database:

docker-compose up -d

API Endpoints

The application provides the following RESTful API endpoints:

• GET /api/posts - Get all posts
• GET /api/posts/{id} - Get a post by ID
• POST /api/posts - Create a new post
• PUT /api/posts/{id} - Update an existing post
• DELETE /api/posts/{id} - Delete a post

API Documentation

The API documentation is available via Springdoc OpenAPI at:

http://localhost:8080/swagger-ui.html

Using cURL

You can interact with the API using cURL commands:

Get All Posts

curl -X GET http://localhost:8080/api/posts

Get Post by ID

curl -X GET http://localhost:8080/api/posts/1

Create a New Post

curl -X POST http://localhost:8080/api/posts \
  -H "Content-Type: application/json" \
  -d '{"userId": 1, "title": "New Post", "body": "This is a new post created with cURL"}'

Update a Post

curl -X PUT http://localhost:8080/api/posts/1 \
  -H "Content-Type: application/json" \
  -d '{"userId": 1, "title": "Updated Post", "body": "This post was updated with cURL"}'

Delete a Post

curl -X DELETE http://localhost:8080/api/posts/1

HTTP Client

The project includes a WebClient-based HTTP client for programmatic API access. The client is implemented in the PostClient class.

Using the HTTP Client

To use the HTTP client in your code:

@Autowired
private PostClient postClient;

// Get all posts
Flux<Post> posts = postClient.getAllPosts();

// Get post by ID
Mono<Post> post = postClient.getPostById(1);

// Create a new post
Post newPost = new Post(null, 1, "New Post", "This is a new post", null);
Mono<Post> createdPost = postClient.createPost(newPost);

// Update a post
Post updatedPost = new Post(1, 1, "Updated Post", "This post was updated", null);
Mono<Post> result = postClient.updatePost(1, updatedPost);

// Delete a post
Mono<Void> deleteResult = postClient.deletePost(1);

Running the Example Client

The project includes an example client that demonstrates how to use the HTTP client. To run it:

./mvnw spring-boot:run -Dspring-boot.run.profiles=client-example

Data Model

The application uses a simple Post model with the following fields:

• id (Integer) - Primary key
• userId (Integer) - User ID associated with the post
• title (String) - Post title (required)
• body (String) - Post content (required)
• version (Integer) - Version for optimistic locking

Testing

The project demonstrates several testing approaches using Testcontainers:

Repository Tests

Tests the repository layer with a real PostgreSQL database using Testcontainers.

./mvnw test -Dtest=PostRepositoryTest

Controller Tests

Tests the controller layer with a real PostgreSQL database using Testcontainers.

./mvnw test -Dtest=PostControllerTest

Integration Tests

Tests the entire application with a real PostgreSQL database using Testcontainers.

./mvnw test -Dtest=SpringBootTestContainerPostgresqlApplicationTests

Project Structure

• src/main/java - Java source code
  • controller - REST controllers
  • model - Data models
  • repository - Data access layer
  • exception - Custom exceptions
• src/main/resources - Application resources
  • data/posts.json - Initial data for the application
  • schema.sql - Database schema definition
• src/test/java - Test source code

License

This project is open source and available under the MIT License.

Author

Hendi Santika

• Email: hendisantika@gmail.com
• Telegram: @hendisantika34