REST - how to create an entry in a collection in different ways?

Question

I need to support different ways of adding a component to a collection of components:

adding "blank" component,

adding a component which is an instance of a class

adding a component which is a copy of another component (paste).
Each way requires different data from the user.

A POST on the collection seems natural, but how do I support the different ways to add a component? It seems as if one verb (POST) is not enough to describe the 3 different operations required (add new, add instance, add copy).

How should this be achieved in a RESTful way?

Answer 1

If the different ways you describe create the same "kind" of resource, then I can image the following ways (if not, these really should be different collections):

One way is to just use a single representation to describe how to create the given resource, something like:

{
   "copy": {
       "href": "copy-from-this-uri"
   },
   "instance-of": "something"
}

Leave it empty to create an empty resource, etc. Another way would be to use completely different mime-types for the 3 different use-cases for the same POST.