W3C home > Mailing lists > Public > public-ldp-wg@w3.org > January 2013

Re: Interaction model vs data model

From: Wilde, Erik <Erik.Wilde@emc.com>
Date: Fri, 25 Jan 2013 10:51:47 -0500
To: Henry Story <henry.story@bblfish.net>
CC: Kingsley Idehen <kidehen@openlinksw.com>, "public-ldp-wg@w3.org" <public-ldp-wg@w3.org>
Message-ID: <CD2866BB.D144%erik.wilde@emc.com>
hello henry.

On 2013-01-24 19:45 , "Henry Story" <henry.story@bblfish.net> wrote:
>We have two elements here: the documents and the protocol (which most of
>us regard HTTP as being a clear case of).  The area of philosophy where
>these two is known as pragmatics. For example one distinguishes between
>the content of a sentence, and what one does with it.  For example given
>the sentence A
>  A: "The blue chair is outside"@en
>Here are two ways to use it
>  B: Joe make it the case that "the blue chair is outside"@en .
>  C: Joe is it the case that "the blue chair is outside"@en ?

this is an excellent example. let's change it just a little, but i think
we're getting close to some of the more confusing things about REST. REST
is not about exchanging facts, it's about exchanging state. most
importantly, it's about engaging in a conversation that may have built-in
rules. let's take this example:

i have a product page and i am composing and POSTing an order for the
product. i am providing all information and send a request that is a
perfectly self-contained order for 42 pieces of that product. if the
protocol says that the server has the freedom to down-adjust the amount of
ordered pieces, and there are only 10 in stock, it would be perfectly fine
if the server state that ends up being created for the order is an order
for 10 pieces. for an HTTP observer it may look strange that i am asking
for 42 and then get a confirmation for an order of 10, but if that's the
rule of the service, then this is a correct conversation.

cheers,

dret.
Received on Friday, 25 January 2013 15:52:47 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:11:44 UTC