Order link and result example

[lhcorralo]

Hi!

Reading the documentation, it says that the link to order an item will be in the links section, with rel=order (well, at least I interpret it). I would consider adding also a proposal for the link.

I know that STAC is using HATEOAS, so the specification at the moment is good ("if rel=order, just shut up and follow that link"), but adding an standard link format would help to implementers.

The href could go like this:

POST http://<server>/<api_url>/collections/<collection_id>/items/<item_id>/order

The example is based in the current hierarchy of collections and items, adding another level, and supposing that an order can retrieve a single item. In addition, I think POST is the appropriate method, as sometimes ordering allows, for example, to provide a notification email.

The result of calling to the order link could be also added as part of the order extension. I guess it could be something like this:

{
  "id": "1234-5678-901234567890",
  "links": [
    {
      "rel": "cancel",
      "href": "http://<server>/<api_url>/collections/<collection_id>/items/<item_id>/order/1234-5678-901234567890"
    }
  ]
}

Following the above definition, cancelling an order would be done by calling.

DELETE http://<server>/<api_url>/collections/<collection_id>/items/<item_id>/order/<order_id>

Thanks!

Luis