Product API Implementation

Overview

This document describes the implementation of REST API endpoints for the Product entity as specified in step 5 of the prompt_pad.md file.

Implementation Details

1. ProductService Enhancements

File: /src/main/java/com/anr/service/ProductService.java

Added the following methods to support full CRUD operations: - findAll() - Retrieves all products - updateProduct(String id, Product product) - Updates an existing product - deleteProduct(String id) - Deletes a product by ID

2. ProductController

File: /src/main/java/com/anr/controller/ProductController.java

Created a new REST controller with the following endpoints:

Endpoints

Method	Endpoint	Description	Response Code
GET	/api/v1/products	List all products	200 OK
GET	/api/v1/products/{id}	Get product by ID	200 OK, 404 Not Found
POST	/api/v1/products	Create new product	201 Created, 400 Bad Request
PUT	/api/v1/products/{id}	Update existing product	200 OK, 404 Not Found
DELETE	/api/v1/products/{id}	Delete product	204 No Content, 404 Not Found

3. Features Implemented

REST Best Practices

• Proper HTTP methods (GET, POST, PUT, DELETE)
• Appropriate HTTP status codes (200, 201, 204, 400, 404, 500)
• JSON request/response format
• RESTful URL structure

OpenAPI/Swagger Documentation

• Complete API documentation with @Operation annotations
• Detailed @ApiResponses for all endpoints
• Request/response schema definitions
• Tagged with "Product Management" for better organization

Error Handling

• Returns 404 when product not found
• Returns 400 for invalid input
• Uses Product.EMPTY pattern for not-found scenarios

Spring Boot Integration

• Uses @RestController and @RequestMapping
• Dependency injection with @Autowired
• Proper media type declarations (APPLICATION_JSON)
• Follows existing controller patterns in the application

Testing the API

Using Swagger UI

Access the Swagger UI at: http://localhost:8080/swagger-ui.html

All Product endpoints will be available under the "Product Management" section.

Sample cURL Commands

1. List all products

curl -X GET http://localhost:8080/api/v1/products

2. Get product by ID

curl -X GET http://localhost:8080/api/v1/products/P001

3. Create a new product

curl -X POST http://localhost:8080/api/v1/products \
  -H "Content-Type: application/json" \
  -d '{
    "id": "P001",
    "name": "Sample Product",
    "description": "This is a sample product",
    "price": "99.99"
  }'

4. Update an existing product

curl -X PUT http://localhost:8080/api/v1/products/P001 \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Updated Product",
    "description": "Updated description",
    "price": "149.99"
  }'

5. Delete a product

curl -X DELETE http://localhost:8080/api/v1/products/P001

Architecture Alignment

The implementation follows the existing application patterns: - Controller Layer: Handles HTTP requests/responses - Service Layer: Contains business logic - Repository Layer: Data access (already existed) - Model Layer: Entity definitions (already existed)

Quality Attributes

✅ Follows Spring Boot 3.x conventions
✅ Uses Jakarta EE annotations (not javax)
✅ Comprehensive OpenAPI documentation
✅ RESTful design principles
✅ Proper HTTP status codes
✅ Consistent with existing codebase style
✅ Build successful (verified)

Next Steps

To fully test the implementation: 1. Start the application: gradle bootRun 2. Access Swagger UI: http://localhost:8080/swagger-ui.html 3. Test endpoints using Swagger UI or cURL commands 4. Optionally add unit tests for the new controller 5. Optionally add integration tests

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Implementation Date: October 22, 2025
Status: ✅ Complete