On Sat, Nov 23, 2013 at 05:07:55PM +0100, Carlos Martín Nieto wrote: > Up to now git has assumed that all servers are able to fix thin > packs. This is however not always the case. > > Document the 'no-thin' capability and prevent send-pack from generating > a thin pack if the server advertises it. > --- > > This is a re-roll of the series I sent earlier this month, switching > it around by adding the "no-thin"
Thanks, I think this moves in the right direction. I wonder if we want to call it "no-thin-pack" just for consistency with the affirmative version in upload-pack. > +The upload-pack server advertises 'thin-pack' when it can generate and > +send a thin pack. The receive-pack server advertises 'no-thin' if > +it does not know how to "thicken" the pack it receives. > + > +A client requests the 'thin-pack' capability when it understands how > +to "thicken" it. > > Client MUST NOT request 'thin-pack' capability if it cannot turn a thin > pack into a self-contained pack. > > +Client MUST NOT send a thin pack if the server advertises the > +'no-thin' capability. As somebody who participated in the discussion, I know why one is in the affirmative and one is in the negative. But I think it might help a reader of the spec to emphasize the difference, and to put the client behavior for each alongside the server behavior, like: The upload-pack server advertises 'thin-pack' when it can generate and send a thin pack. A client requests the 'thin-pack' capability when it understands how to "thicken" it, notifying the server that it can receive such a pack. A client MUST NOT request the 'thin-pack' capability if it cannot turn a thin pack into a self-contained pack. Receive-pack, on the other hand, is assumed by default to be able to handle thin packs, but can ask the client not to use the feature by advertising the 'no-thin' capability. A client MUST NOT send a thin pack if the server advertises the 'no-thin' capability. The reasons for this asymmetry are historical. The receive-pack program did not exist until after the invention of thin packs, so historically the reference implementation of receive-pack always understood thin packs. Adding 'no-thin' later allowed receive-pack to disable the feature in a backwards-compatible manner. -Peff -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html