Question

In a RESTful application, how do we differentiate between an “action” and an HTTP verb (GET, POST, PUT, DELETE)?

For example, as I understand it, a GET request to the resource /products should return a list of all products. A POST request to /products should create a new product. How, then, does the user request the original form which is used to create the product? My initial response would have been a GET request to the same URI, but as mentioned above, that should return a list of all products – not a blank form for creating a product.

In most frameworks I’ve researched, this problem is solved by making the “action” part of the URI. For example, a POST request to /products/create would create a new product, whereas a GET request to /products/create would give the blank form for creating a product. To get a list of all products would be a GET request to either /products or /products/get, /products/read, etc. depending on the framework in question. This approach resolves the ambiguity above, but it conflicts with what I’ve read about traditional REST design.

Answer 1

IMHO, the best option is to make the request method a part of controller’s action.

Lets say you are accessing http://who.cares/product/42 or http://who.cares/product/42/specification . This query to webserver would translate as Product controller. The actions name should be created by combining request method and command:

DELETE "http://who.cares/product/42"

    controller: "Product", 
    action:     "deleteProduct()" 


GET "http://who.cares/product/42/details"

    controller: "Product", 
    action:     "getDetails()"


POST "http://who.cares/product/42/review"

    controller: "Product", 
    action:     "postReview()"


GET "http://who.cares/products/ 

    controller: "Products", 
    action:     "getProducts()"


POST "http://who.cares/products/ 

    controller: "Products", 
    action:     "postProducts()"