Re: PaceServiceError comments

[Walter Underwood <wunder@xxxxxxxxxx>]

--On Wednesday, June 23, 2004 08:57:55 AM -0400 Robert Sayre 
<mint@xxxxxxxxxxxxxxx> wrote:
> Can anyone give an example of a valid use case for the last paragraph of
> Section 9.1.1?
>
> Robert Sayre
>
> [1] http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9

Specifically this, portion, I presume, "The important distinction here is
that the user did not request the side-effects ..."

How about four examples?

Search engine results are a GET, because I am fetching a resource,
that is, the most relevant documents for my query. When I do that
GET, all sorts of things are recorded for later use by the search
engine. That is the server's decision, not mine. All I want are
the results.

When I click on a spelling suggestion at Yahoo or Google, that
click reinforces the reliability of that suggestion and makes it
more likely that it will show to others. [This is a guess, but
it is plausible. It is also spammable, sigh.]

When I click on an ad, I GET the contents of the ad. As that
happens, the click is recorded and the advertiser is billed for my
click. I intend to follow the ad, the billing is an unrequested
side-effect. In real life, the click is recorded in one place, then
I am redirected to the ad target, but it is still conceptually a
single GET. The click could be recorded at the target site.

This last example is one that is close to the edge on GET/POST.
At Findory News (http://findory.com/) when I click on a news article,
that click is recorded (again with a redirect) and my reading preferences
are used to change the recommended articles the next time I visit
Findory. This is one that stretches things a bit, where the primary
intent is fetching a resource, but my secondary intent is to update
my recommendations at Findory. Still, I think GET is the clear choice
over POST. Idempotence is probably the tie-breaker here, since GET'ing
the same article twice will have exactly the same effect as GET'ing it
once.

wunder
PS: No, I don't click on ads. That was a hypothetical example.
--
Walter Underwood
Principal Architect
Verity Ultraseek