Application Routes:

User

api/v1/auth/signup (POST)
api/v1/auth/signin (POST)
api/v1/users (GET)
api/v1/users/b3c84a4e-f72f-4eb7-8abd-b4d3f11afc98 (Single GET) 
api/v1/users/b3c84a4e-f72f-4eb7-8abd-b4d3f11afc98 (PATCH)
api/v1/users/b3c84a4e-f72f-4eb7-8abd-b4d3f11afc98 (DELETE) 

Category

api/v1/categories/create-category (POST)
api/v1/categories (GET)
api/v1/categories/dd42d45f-12ab-4c3e-9541-0f63d052d467 (Single GET) 
api/v1/categories/dd42d45f-12ab-4c3e-9541-0f63d052d467 (PATCH)
api/v1/categories/dd42d45f-12ab-4c3e-9541-0f63d052d467 (DELETE)

Books

api/v1/books/create-book (POST)
api/v1/books (GET)
api/v1/books/dd42d45f-12ab-4c3e-9541-0f63d052d467/category (GET)
api/v1/books/0080a0d9-deaa-42a4-a930-effb5cb856f1 (GET)
api/v1/books/0080a0d9-deaa-42a4-a930-effb5cb856f1 (PATCH)
api/v1/books/0080a0d9-deaa-42a4-a930-effb5cb856f1 (DELETE)

Orders

api/v1/orders/create-order (POST)
api/v1/orders (GET)