REST pattern create, update and delete same endpoint - api

Question

I have a page where I list the books of a school. The user can update a book, add a new book or delete an existing book. All actions must be saved when the form is submitted.
How can i map a rest API for that? I could take advantage of the endpoints i already have.
UPDATE
PUT /schools/1/books
{
"books": [
{
"id": "1",
"name": "Book 1"
}
]
}
CREATE
POST /schools/1/books
{
"books": [
{
"name": "Book 2"
},
{
"name": "Book 3"
}
]
}
DELETE
DELETE /schools/1/books
{
"books": [
{
"id": 2
}
]
}
But I need everything to run on the same transaction, and wouldn't make sense to submit 3 requests.
I also thought of creating a new endpoint where I would create books that doesn't exists, update books that exists, and remove books that are not present on the request.
So if this school has Book 1 and Book 2, I could update Book 1, create New Book and remove Book 2 with:
PUT /schools/1/batch-books
{
"books": [
{
"id": "1",
"name": "Updated Book 1"
},
{
"name": "New Book"
}
]
}
Do you guys have other options?

Answer 1

I would separate things into different resources:
/books and /books/{id} for books. They gives book details and allow to manage them.
/schools and /schools/{id} for schools. They gives school details and allow to manage them.
/schools/{id}/books to associate books in schools. I mean books that are available within a school. This resource provides methods to manage a list of links to books.
Let me detail the last resource. In fact, this is related to hypermedia. In the following, I'll use JSON-LD but you're free to use other hypermedia tools.
A GET method will return the list of associated books:
GET /schools/1/books
[
{
"#id": "http://api.example.com/books/1895638109"
},
{
"#id": "http://api.example.com/books/8371023509"
}
]
You can notice that you can implement mechanisms to allow to get more details if needed. Leveraging the Prefer header seems to be a great approach (see the link below for more details).
In addition, you could provide the following methods:
POST to add a link to the school. The request payload would be: {"#id": "http://api.example.com/books/1895638109"}. The response should be a 201 status code.
DELETE to delete a specific link from a school. A query parameter could be used to specify which link to remove.
PATCH to allow to do several operations in one call and actually provide some batch processing. You can leverage at this level JSON-PATCH for the request processing. Within the response, you could describe what happens. There is no specification at this level so you're free to use what you want... Here is a sample for the request payload:
PATCH /schools/1/books/
[
{
"op": "add", "value": "http://api.example.com/books/1895638109"
},
{
"op": "remove", "path": "http://api.example.com/books/8371023509"
}
]
Reading the following links could give you some hints on the way to design such use case:
Implementing bulk updates within RESTful services: http://restlet.com/blog/2015/05/18/implementing-bulk-updates-within-restful-services/
On choosing a hypermedia type: http://sookocheff.com/post/api/on-choosing-a-hypermedia-format/
Creating Client-Optimized Resource Representations in APIs: http://www.freshblurbs.com/blog/2015/06/25/api-representations-prefer.html
Hope it helps you,
Thierry