User

POST: Sign-in (/auth/sign-in)
POST: Sign-up (/auth/sign-up)

Author

GET: List (/authors)
POST: Create (/authors)
GET: Show (/authors/:id)
PUT: Update (/authors/:id)
DELETE: Delete (/authors/:id)\

Book

GET: List (/books)
POST: Create (/books)
GET: Show (/books/:id)
PUT: Update (/books/:id)
DELETE: Delete (/books/:id)