Re: PATCH vs PUT w/Content-Range

Updates should be atomic -- the entire patch should be applied or 
entirely failed.  I will make that explicit.  Thanks!

Lisa

On Apr 29, 2004, at 9:32 AM, Alex Rousskov wrote:

> On Thu, 29 Apr 2004, Jim Luther wrote:
>
>> I like the PATCH proposal because it provides clients with:
>>
>> 1 - The ability to change the size of a resource independent or in
>> addition to changing the data. PUT doesn't do this unless you change
>> the current meaning of the byte-content-range-spec passed in a
>> Content-Range header so that */100 means "set the length of the
>> resource to 100 -- truncate the resource if its current length is more
>> than 100, zero extend the resource if its current length is less than
>> 100".
>
> How does PATCH proposal allow to separate data from its size?
>
> I was always thinking that in HTTP world the "size of the resource"
> and "size of [resource] data" are always the same. That is, "size" is
> not a property that can be changed without changing resource
> content/data. Can you clarify why would you want to separate the two
> concepts and would "zero" definition depend on content type or patch
> format?
>
>> 2 - The ability to change multiple ranges [...] with a single
>> request.
>
> Multi-hunk patches are indeed very useful to support atomic updates.
> draft-dusseault-http-patch-01 does not seem to have error codes
> related to situations where some of the patch hunks failed while
> others succeeded. Are all updates assumed to be atomic (i.e., all or
> nothing)? Should this assumption be made explicit? Sorry if I missed
> it in the draft.
>
> Thanks,
>
> Alex.

Received on Thursday, 29 April 2004 12:39:35 UTC