Range 0:0 for the whole payload

[roman-khimov]

Is your feature request related to a problem? Please describe.

I'm always frustrated when I think of how S3 gateway processes GET requests. Most of the time it goes https://github.com/nspcc-dev/neofs-s3-gw/blob/bf5a07fa5c4d6b4bc21a489b600b7548c78db6ab/internal/neofs/neofs.go#L547-L560 route, fetching the whole object from storage (regular GET operation). While in fact the gateway doesn't need and doesn't use the header in any way (see https://github.com/nspcc-dev/neofs-s3-gw/blob/bf5a07fa5c4d6b4bc21a489b600b7548c78db6ab/api/layer/object.go#L107-L123 also).

Describe the solution you'd like

We're missing easy ways to get payload of the object only. Take HTTP range requests for example (https://www.rfc-editor.org/rfc/rfc7233#section-2), much more rich semantics is provided there. We can't do all of it immediately, our range parameters are unsigned, but we can give an additional meaning to otherwise useless 0:0 and return whole payload in this case. S3 will get the data it needs to, no more and no less, we'll send less messages and will be able to benefit from other node-side optimizations like nspcc-dev/neofs-node#2925 (omitting header processing at all).

Describe alternatives you've considered

Keep things as is or extend range requests with additional parameters.

[roman-khimov]

Or 0:Uint64Max maybe.

[cthulhu-rider]

i like treating zero range as whole payload request. It is unlikely that it can be interpreted other way

Or 0:Uint64Max maybe.

maxuint64 is 16EB which is enormous nowadays, but still a range of a specific size. So zero wins to me

[AnnaShaleva]

Will be useful for NeoFS BlockFetcher as far, +1 from NeoGo side.

[roman-khimov]

Related to #276.

[roman-khimov]

It's not critical, but we have #276 and in general MaxUint64 is the maximum that our protocol supports, so if that's exactly the size of the object --- we're not breaking anything with 0:MaxUint64. But 0:0 is less bytes transmitted over the wire (if anyone cares about them).

🚀 for 0:0
🎉 for 0:MaxUint64