Subject: Re: [apps-discuss] NEW RELATION: 'action' version update

From: Darrel Miller <[email-masked]>
Date: Tue, 27 Aug 2013 13:47:15 -0400

Unfortunately, I agree that this latest revision of the action link
relation spec does not add value beyond what can be done directly with
link relations.

However, I don't believe that is the case with the original action
link relation spec. [1]

The original spec defined the action link relation type to convey just
enough semantics to allow a client to activate that link.  The
semantics of the link relation were "perform an unsafe request by
performing a POST to the target resource using an empty body".

Some user agents have no need to understand the semantics of "start",
"restart", "MoveAction", "PlayAction", etc.  As long as the hypermedia
affordance can be rendered and  interpreted by the user, why does the
user-agent need to know anything more that POST an empty body to this
processing resource upon activation?

The feedback received on the link relations list was that this type of
link relation would encourage RPC like interactions and the proposal
was rejected.  I still have not completely understood why a
representation that includes a body is OK but a representation that
has no body is considered RPC like.

>From what I am reading here, in this thread is that rel="start" or
rel="restart" are considered valid interactions.  Then I see no reason
why the more generic and much more widely applicable "action" relation
would not be considered valid also.

Considering the example James gave, why not this,

 Link: <start-action?id=1212>; rel="action"; title="Start"
 Link: <restart-action?id=1212>; rel="action"; title="Restart"

Darrel Miller

[1] http://tools.ietf.org/html/draft-ioseb-dzmanashvili-action-link-relation-00

On Tue, Aug 27, 2013 at 11:38 AM, James M Snell <[email-masked]> wrote:
> On Tue, Aug 27, 2013 at 6:16 AM, Mark Baker <[email-masked]> wrote:
>>
>> On 2013-08-27 6:15 AM, "Julian Reschke" <[email-masked]> wrote:
>>> It seems that you are just adding an indirection mechanism. Why is that
>>> necessary?
>>
>> Agreed. The action-types should be registered as the relations.
>>
>> Also, you might consider reusing the good work of the folks behind
>> Schema.org;
>>
>> http://schema.org/Action
>>
>
> Not to mention activitystrea.ms where many of these verbs already
> exist (and could easily be used as link relations themselves).
>
>   Link: <start-action>; rel="start"
>   Link: <restart-action>; rel="restart"
>
> Would be generally easier overall.
>
> - James
>
>>