Re: proposed change to a spec

On Mon, 2011-02-28 at 03:23 +0000, Nathan wrote:
> Nathan wrote:
> > David Booth wrote:
> >> On Mon, 2011-02-28 at 02:06 +0000, Nathan wrote:
> >>> I'm thinking about asking for HTTP-BIS to be changed, specifically 
> >>> [[
> >>>     A "representation" is information in a format that can be readily
> >>>     communicated from one party to another. A resource representation is
> >>>     a realization (copy/instance) of the state of that resource, as
> >>>     observed at some point in the past (e.g., in a response to GET) 
> >>> or to
> >>>     be desired at some point in the future (e.g., in a PUT request).
> >>> ]]
> >>>
> >>> does anybody here object?
> >>
> >> Yes, vehemently.  Obviously what you GET is some reflection of the state
> >> of the resource, but the client cannot assume that the information it
> >> receives reflects the *full* state of the resource.  Any amount of
> >> complexity may be hidden behind the HTTP interface.  In fact, that
> >> complexity may not even be deterministic.  Consider today's weather in
> >> Oaxaca:
> >> http://www.weather.com/weather/today/Oaxaca+Mexico+MXOA0069 The full 
> >> state of that resource certainly cannot be conveyed in the HTTP
> >> response.
> > 
> > what is the resource? information about the weather in Oaxaca Mexico, or 
> > "the weather" in Oaxaca Mexico?

That resource provides *information* about the weather in Oaxaca.

> > 
> > do you fundamentally disagree with the notion of "information resource", 
> > such that the URI above in fact refers to the real world weather in that 
> > place at any instant in time?
> 
> just for the sake of clarification, you may notice that weather.com 
> clearly says that 
> http://www.weather.com/weather/today/Oaxaca+Mexico+MXOA0069 is
> 
> title: "Oaxaca Weather Forecast and Conditions"
> description: "Oaxaca weather forecast and weather conditions. Today’s 
> Oaxaca weather plus a 36 hour forecast and Doppler radar from weather.com."
> 
> they certainly do not purport that the uri refers to "the weather in 
> Oaxaca", and clearly state that it's information about the weather in 
> Oaxaca, a forcast and a summary of the weather conditions.
> 
> The text I offered above, holds true for this resource.

For the sake of illustration, let us assume that the web server at
http://www.weather.com/weather/today/Oaxaca+Mexico+MXOA0069
is connected directly to an outdoor thermometer that is measuring the
real world temperature in Oaxaca.  Clearly, the web page that is
returned does not reflect the full state of the weather in Oaxaca.

It sounds like you are attempting to artificially differentiate between
the view (or subset) of the state that is used in constructing the
returned representation, from the rest of the resource state, which is
hidden behind the HTTP interface.   Why make that distinction?  All that
matters is that it returned a representation containing today's weather
report.



-- 
David Booth, Ph.D.
http://dbooth.org/

Opinions expressed herein are those of the author and do not necessarily
reflect those of his employer.

Received on Monday, 28 February 2011 04:11:21 UTC