[JITERA] Implement PATCH /books/:id Endpoint

Created by: chi-jitera

Overview

This pull request addresses the implementation of the PATCH /books/:id endpoint, which allows for updating book details in the system. The endpoint is designed to handle updates to various fields of a book, with specific validation and error handling in place.

Changes Explained

• Route Definition: The route for the PATCH request is defined in /routes/bookRoutes.js. This sets up the endpoint to listen for PATCH requests at the specified URL.

• Controller Implementation: The controller function patchBook is implemented in /controllers/bookController.js. This function acts as the intermediary between the route and the service layer, handling the request and response.

• Business Logic: The core business logic for updating a book is encapsulated in the patchBook function located in /services/bookService.js. This function processes the update request and interacts with the database to apply the changes.

• Validation: The implementation includes validation logic that checks the fields present in the request. Specifically, it ensures that the publishedYear field is valid, rejecting any invalid values to maintain data integrity.

• Error Handling: The endpoint is equipped with error handling mechanisms that return a 404 status code if the specified book is not found, and a 400 status code for any validation errors encountered during the request.

No further action is required for the PATCH /books/:id endpoint as it is fully implemented and functional.