Re: Enhancements to git-protocoll

[Junio C Hamano <gitster@pobox.com>]

Shawn Pearce <spearce@spearce.org> writes:

> We sort of want this in Gerrit Code Review to pass reviewer names on
> the command line of git push, making it easier for users to upload a
> code review. The idea is similar to what happens with gcc accepting
> linker flags that are just passed onto the linker.

For reviewer names, authentication cookies and things of that nature
where the extra pieces of information affect the outcome in a way
that does not have to change how the underlying protocol exchange
works, such an additional one-way channel from the pusher to pushee
to carry auxiliary information would be sufficient.  The server may
decide to accept otherwise forbidden, or reject otherwise permitted,
push based on the extra information given, for example, and that is
an example of an enhancement that does not have to change how the
underlying protocol exchange works.

The way to expose the extra information parsed by Git to the server
side could be made into calling out to hooks, and at that point,
gitolite would not even have to know about the pack protocol.
Perhaps the interface to such a hook may be "hook can tell Git to
abort the communication by exiting non-zero, after giving a message
to its standard output".

It is a separate matter if it makes sense to add another channel
that goes the other way on demand (i.e.  taking the end-user
response from the pusher and giving it to the pushee, and then
allowing the pushee change its behaviour in a way more than just
simply aborting the connection but performing a useful alternative
operation)---I doubt it is.