[apps-discuss] JSON-Home widget example

Jan Algermissen <jan.algermissen@nordsc.com> Mon, 08 April 2013 11:33 UTC

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From: Jan Algermissen <jan.algermissen@nordsc.com>
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Date: Mon, 08 Apr 2013 13:11:42 +0200
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Cc: Mark Nottingham <mnot@mnot.net>
Subject: [apps-discuss] JSON-Home widget example
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Hi Mark,

curious about your opinion on the following.

The example you provide in the draft[1] troubles me a bit since a real-life, similar case made me look at it from a different angle.

    "http://example.org/rel/widgets": {
         "href": "/widgets/"
       "http://example.org/rel/widget": {
         "href-template": "/widgets/{widget_id}",
         "href-vars": {
           "widget_id": "http://example.org/param/widget"

What we have here is sort of a standard pattern for making available 'a bag of things' via HTTP.

For example, a bunch of orders can be straight forward exposed as


and knowing that

  "http://example.org/rel/orders" : { "href" : "/orders" }

pretty much implies something like /orders/{orderId}, including the idea that adding an order is likely done with a POST to /orders and that editing an order is (maybe) achieved with PUT/PATCH/DELETE.

What troubles me is that JSON Home currently makes it necessary to define two link relations to cover a standard (in a sense) use case that could be covered with just one link relation. Or, in other words, the two link rels somehow semantically overlap, yet demand two 'specifications'. Think in terms of violating DRY.

Can't think of an improvement that does not introduce the 'pattern' into the spec, but I am nevertheless much interested in your view.

Maybe an optional {widget_id} and one rel with appropriate definition does the trick already, but hard to seperate the hints. Dunno...


[1] http://tools.ietf.org/html/draft-nottingham-json-home-02