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Comment LC-2036
:
Commenter: Mark Baker <distobj@acm.org>

or
Resolution status:

4.1.5 Alteration of HTTP Header Values

RFC 2616 already says a lot about this. See sec 13.5.2 for example.

"The theoretical idempotency of GET requests is not always respected
by servers. In order, as far as possible, to avoid mis-operation of
such content, proxies should avoid issuing duplicate requests and
specifically should not issue duplicate requests for comparison
purposes."

First of all, do you mean "safe" or "idempotent"? That you refer only
to GET suggests safety, but the second sentence suggests you are
referring to idempotency. So please straighten that out. Oh, and
there's nothing "theoretical" about GET's safety or idempotency; it's
by definition, in fact.

Secondly, if the server changes something important because it
received a GET request, then that's its problem. Likewise, if it
changes something non-idempotently because it received a PUT request,
that's also something it has to deal with. In both cases though, the
request itself is idempotent (and safe with GET), so I see no merit to
that advice that you offer ... unless of course the problem you refer
to is pervasive which clearly isn't the case.

I also wonder if most of 4.1.5 shouldn't just defer to 2616. As is,
large chunks of this section (as well as others) specify a protocol
which is a subset of HTTP 1.1. (see also the RFC 2119 comment above)
(space separated ids)
(Please make sure the resolution is adapted for public consumption)


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