Re: i22: ETags on PUT responses

sön 2008-01-06 klockan 17:20 +0100 skrev Werner Baumann:

> The only use case, where a client can make use of the etag without 
> further knowledge and guarantee is DELETE. It suffices to know, that the 
> resource has not been modified by someone else in between. In all other 
> use cases, the client must know, whether there are manipulations by the 
> server that might conflict with what the client wants to do.

PUT is also in this category, same as DELETE. The transform applied by
the server on the stored resource MUST be repeatable and not dependent
on seeing that transform in future PUTs to the same resource.

This comes from partially the fact that PUT is a non-indempotent
request, just as GET/DELETE. There must be no harm done on the server by
repeating the same PUT.

Regards
Henrik

Received on Sunday, 6 January 2008 23:31:29 UTC