On 2017-06-12 06:58 PM, Jacob Keller wrote:
Hi,
There's no actual code yet, (forgive me), but I've been thinking back
to a while ago about attempting to find a way to share things like
refs/notes, and similar refs which are usually not shared across a
remote.
By default, those refs are not propagated when you do a push or a
pull, and this makes using them in any project which has more then one
repository quite difficult.
I'm going to focus the discussion primarily on refs/notes as this is
what I am most interested in, but I think similar issues exist for
refs/grafts and refs/replace, and maybe other sources?
More formal support for custom ref namespaces would be a boon. For
example, we have our nightly builds create a "build/w.x.y-z" ref (we
only want to tag official releases). Sharing those refs is not hard,
but a bit obscure.
For branches, we already have a system to share the status of remote
branches, called "refs/remotes/<remote-name>/<branch-name>"
This hierarchy unfortunately does not keep space for non-branches,
because you can't simply add a "refs/remotes/notes/<>" or
"refs/remotes/<name>/notes" to this as it would be ambiguous.
Now, you might just decide to push the refs/notes directly, ie:
git push origin refs/notes/...:refs/notes/...
Unfortunately, this has problems because it leaves no standard way to
distinguish your local work from what is on the remote, so you can't
easily merge the remote work into yours.
There was a related discussion in the run-up to 1.8.0, about a "remote
tag namespace" to support having different remotes with the same tag
name for different objects. See these messages and their surrounding
threads:
http://public-inbox.org/git/AANLkTikeqsg+qJ0z4iQ6ZmKL=_HB8YX_z20L=dFFApmA@xxxxxxxxxxxxxx/
http://public-inbox.org/git/AANLkTi=yFwOAQMHhvLsB1_xmYOE9HHP2YB4H4TQzwwc8@xxxxxxxxxxxxxx/
http://public-inbox.org/git/201102020322.00171.johan@xxxxxxxxxxx/
The discussion explored, among other things, making
refs/remotes/$remote/* a mirror of a remote's own refs/* hierarchy
(well, within reason -- I think there are limits to what should be
mirrored).
So I like your refs/tracking proposal, and hope that it aims for
mirroring a remote's refs, to eventually replace refs/remotes entirely.
M.
For example, if Alice creates a new note and pushes it, then Bob
creates a different note on the same commit, he needs to be able to
merge Alice's changes into his note, just like one would do when two
people commit to the same branch.
Today, he must pull the remote notes into a separate location, (since
pulling directly into refs/notes will overwrite his work), and then
update, and then push.
Because this is not standardized, it becomes unwieldy to actually
perform on a day to day basis.
I propose that we add a new "refs/tracking" hierarchy which will be
used to track these type of refs
We could even (long term) migrate refs/remotes into refs/tracking
instead, or provide both with the refs/remotes being pointers or
something like that..
Essentially, refs/notes would be pulled into
refs/tracking/<remote>/notes/* or something along these lines.
Then, git notes would be modified to be able to have commands to
"pull" and "push" notes which would fetch the remote, and then attempt
a merge into the local notes, while a push would update the remote.
I chose "tracking" because it sort of fits the concept and does not
include things like "remote-notes" or "remotes-v2" which are a bit
weird.
I'm posting this on the mailing list prior to having code because I
wanted to get a sense of how people felt about the question and
whether others still felt it was an issue.
Essentially the goal is to standardize how any refs namespace can be
shared in such a way that local copies can tell what the remote had at
a fetch time, in order to allow easier handling of conflicts between
local and remote changes, just like we do for branches (heads) but
generalized so that other refs namespaces can get the same ability to
handle conflicts.
Thanks,
Jake