Re: [hybi] [Uri-review] ws: and wss: schemes

[David Booth <[e-mail]>]

On Tue, 2009-08-11 at 17:23 -0700, Maciej Stachowiak wrote:
> On Aug 9, 2009, at 6:52 PM, David Booth wrote:
> 
> > On Fri, 2009-08-07 at 21:30 -0400, Daniel R. Tobias wrote:
> >> On 7 Aug 2009 at 9:16, David Booth wrote:
> >>
> >>> Note that I am talking about the *scheme*, not the protocol.  In
> >>> essence, a URI prefix such as "http://wss.example/" can be defined  
> >>> that
> >>> would serve the same purpose as a "wss:" scheme: an agent that
> >>> recognizes this prefix will know to attempt the WSS protocol.
> >>
> >> It seems like a bad idea to me, to have to build special exceptions
> >> to how a user agent processes URIs, where the protocol specified in
> >> the URI isn't actually the one that is used, based on "magic strings"
> >> within other parts than the scheme.
> >
> > I can't see that as a significant issue, as there is only a trivial
> > difference between dispatching based on the string prefix
> > "http://wss.example/" and the string prefix "wss:".  Both are simple,
> > constant strings and both are equally "magic": they cause agent to
> > attempt the WSS protocol.
> 
> The difference is that "http://wss.example/" already has a meaning,  
> which is not the intended one. Whereas "wss:" currently has no  
> meaning. Thus the former has greater risk of either colliding with an  
> existing resource, or being misinterpreted by a legacy client (instead  
> of just rejected).

That's not a risk, that's the *intent*.  The point is that a prefix like
"http://wss.example/" gives agents that do not know the WSS protocol the
possibility of doing something useful with the URI, by falling back to
the HTTP protocol, whereas if a prefix like "wss:" were used those same
agents would have to reject it entirely.  The "http://wss.example/" URI
still retains its meaning as an http URI, but it gains *additional*
meaning as a WSS URI for those agents that know how to handle the WSS
protocol. 


-- 
David Booth, Ph.D.
Cleveland Clinic (contractor)

Opinions expressed herein are those of the author and do not necessarily
reflect those of Cleveland Clinic.