#+TITLE:Comparison of Hypermedia Message Formats
#+AUTHOR: Arne Brasseur
#+email: arne@arnebrasseur.net
#+INFOJS_OPT: view:info toc:nil
#+BABEL: :session *ruby* :cache yes :results output graphics :exports both :tangle yes

* Form Controls / Actions

| Format          | href                            | name/id  | title/caption | method    | media-type      | fields                           | schema      | string template | structured template |
|-----------------+---------------------------------+----------+---------------+-----------+-----------------+----------------------------------+-------------+-----------------+---------------------|
| HTML5           | action=""                       |          |               | method="" | enctype=""      | yes                              |             |                 |                     |
| halo            | "href"                          | json key |               | "method"  | "content-type"  |                                  | "schema"    | "template"      |                     |
| siren           | "href"                          | "name"   | "title"       | "method"  | "type"          | "fields"                         |             |                 |                     |
| mason           | "href"                          | json key | "title"       | "method"  | depends on type |                                  | "schemaUrl" |                 | "template"          |
| Collection+JSON | "href" (query)/current resource |          | "prompt"      |           |                 |                                  |             |                 |                     |
| Hydra           | current resource                | "@type"  |               | "method"  |                 | "expects": {"supportedProperty"} |             |                 |                     |

| Format          | Name       | Title    | Type    | Value   |
|-----------------+------------+----------+---------+---------|
| Siren           | "name"     |          | "type"  | "value" |
| Collection+JSON | "name"     | "prompt" |         | "value" |
| Hydra           | "property" |          | "range" |         |

** HTML

   [[http://www.w3.org/TR/html5/forms.html][W3C: HTML5 Forms]]

** halo+json

   [[https://gist.github.com/mikekelly/893552][Gist: A sketch of application/halo+json and application/halo+xml]]

   #+BEGIN_SRC json
     {
       "_controls": {
         "widgetate": {
           "href": "/widget/{newID}",
           "method": "PUT",
           "content-type": "application/xml",
           "schema": null,
           "template": "<widget>\\n <name>{{name}}</name>\\n\\n <blobs>\\n {{#blobs}}\\n <blob>\\n {{#first}}\\n <first>true</first>\\n {{/first}}\\n <contents>{{contents}}</contents>\\n </blob>\\n {{/blobs}}\\n </blobs>\\n\\n {{#is_empty}}\\n <note>This is an empty widget</note>\\n {{/is_empty}}\\n</widget>\\n"
         }
       }
     }
   #+END_SRC

** Siren

   [[https://github.com/kevinswiber/siren][Siren Home page]]


   #+BEGIN_SRC json
     {
       "actions": [
         {
           "name": "add-item",
           "title": "Add Item",
           "method": "POST",
           "href": "http://api.x.io/orders/42/items",
           "type": "application/x-www-form-urlencoded",
           "fields": [
             { "name": "orderNumber", "type": "hidden", "value": "42" },
             { "name": "productCode", "type": "text" },
             { "name": "quantity", "type": "number" }
           ]
         }
       ]
     }
   #+END_SRC

** Mason

   #+BEGIN_SRC json
     {
       "@actions": {
         "is:delete-issue": {
           "type": "void",
           "href": "...",
           "method": "DELETE",
           "title": "Delete issue"
         }
       }
     }
   #+END_SRC

   #+BEGIN_SRC json
     {
       "@actions": {
         // JSON action with schema reference
         "is:project-create": {
           "type": "json",
           "href": "...",
           "title": "Create new project",
           "schemaUrl": "..."
         },
         // JSON action with default template
         "is:update-project": {
           "type": "json",
           "href": "...",
           "title": "Update project details",
           "template": {
             "Code": "SHOP",
             "Title": "Webshop",
             "Description": "All issues related to the webshop."
           }
         }
       }
     }
   #+END_SRC


https://github.com/JornWildt/Mason/blob/master/Documentation/Mason-draft-1.md#actions
** Collection+JSON

   CJ does not have a form-like representation. It does allow
   resources to contain a "template", which is really a list of form
   fields, and a client can use HTTP methods against the same endpoint
   to perform CRUD operations. In addition CJ provides "queries" for
   basic GET based operations.

   #+BEGIN_SRC json
     {
       "template" :
       {
         "data" :
         [
           {"prompt" : STRING, "name" : STRING, "value" : VALUE},
           {"prompt" : STRING, "name" : STRING, "value" : VALUE},
           ...
           {"prompt" : STRING, "name" : STRING, "value" : VALUE}
         ]
       }
     }
   #+END_SRC

   #+BEGIN_SRC json
     {
       "queries" :
       [
         {
           "href" : "http://example.org/search",
           "rel" : "search",
           "prompt" : "Enter search string",
           "data" :
           [
             {"name" : "search", "value" : ""}
           ]
         }
       ]
     }
   #+END_SRC
** JSON-LD + Hydra

   Example taken from [[http://sookocheff.com/posts/2014-03-11-on-choosing-a-hypermedia-format/][this blog post]]

   JSON-LD itself does not have form like controls, only
   linking. Hydra introduces an "operation" property for this purpose.

   #+BEGIN_SRC json
     {
       "@context": [
         "http://www.w3.org/ns/hydra/core",
         {
           "@vocab": "https://schema.org/",
           "image": { "@type": "@id" },
           "friends": { "@type": "@id" }
         }
       ],
       "@id": "https://api.example.com/player/1234567890/friends",
       "operation": {
         "@type": "BefriendAction",
         "method": "POST",
         "expects": {
           "@id": "http://schema.org/Person",
           "supportedProperty": [
             { "property": "name", "range": "Text" },
             { "property": "alternateName", "range": "Text" },
             { "property": "image", "range": "URL" }
           ]
         }
       }
     }
   #+END_SRC