Re: Bookmark 'stability'

Mike Kelly wrote:
> 
> Hence why we have 'entry points' which /are/ the stable URIs of a
> hypermedia application. This is what distinguishes them as an entry
> point - they are an resource a client can assume exists (i.e.
> bookmark).
>

This notion of 'entry points' is a common misconception about REST.
The 'bookmark' relation is not a declaration of status.  Every
representation in a REST application is a potential entry point, that's
what the hypertext constraint is all about -- there's no set application
flow.

Think of a shopping cart app -- I may go back and change the ship-to
address at a later point than I was initially asked, whereas you did
not.  I may have entered from a product page, whereas you may have
entered from a special-offer ad.  Does the fact that we used different
starting points and followed a different path through the process, mean
we used separate shopping-cart apps?

Roy's whole point with bookmarking is to contrast with the RPC style,
where you can't go back and edit a ship-to address, you can only go
back to step one and repeat the whole process.  I may bookmark the
"payment" page because the wife's out shopping with the credit card, so
I want to come back later and *that* is my entry point.

>
> If every URI in your app was supposed to be bookmarkable then the
> term 'entry point' would be meaningless.
> 

But it *is* meaningless to a RESTful system, which is my whole point in
this thread.

-Eric