Re: Grafts workflow for a "shallow" repository...?

[Michael J Gruber <git@drmicha.warpmail.net>]

Björn Steinbrink venit, vidit, dixit 16.09.2008 10:09:
> On 2008.09.15 23:25:10 -0700, Junio C Hamano wrote:
>> "Shawn O. Pearce" <spearce@spearce.org> writes:
>>
>>> Martin Langhoff <martin.langhoff@gmail.com> wrote:
>>>> Here is my attempt at a "let's publish a shallow repository for branch
>>>> of moodle". Let me show you what I did...
>>> ...
>>>>  # 1.7 was a significant release, anything earlier than that
>>>>  # is just not interesting -- even for pickaxe/annotate purposes
>>>>  # so add a graft point right at the branching point.
>>> ...
>>>> Is this kind of workflow (or a variation of it) supported? For this to
>>>> work, we should communicate the grafts in some push operations and
>>>> read them in clone ops - and perhaps in fetch too.
>>> ...
>>> I think that in this case the best thing to do is give users
>>> a shell script that does roughly:
>>>
>>> 	git init
>>> 	echo $BASE >.git/info/grafts
>>> 	git remote add -f origin $url
>>> 	git checkout -b master origin/master
>>>
>>> Sign the script, and let users verify it before executing.  You may
>>> also want a script to drag in the history behind by removing the
>>> graft and fetching $BASE^, but that is hard because your repository
>>> already "has" that.
>> Why not just filter-branch _once at the origin_ and publish the result?
> 
> I think the idea was to have a shallow clone starting at a certain
> point, as opposed to the --depth option, where you cannot specify a
> starting point, but only the depth of the clone.

That's what Junio suggests:

chop the history by introducing an appropriate graft
make it "permanent" by filter-branching (and remove from info/grafts).

Now you have a disconnect dag. clone/push/whatever works on the
"components" given by connected branches.

Note that in this approach all history after the "chopping point" will
be rewritten, i.e. get new sha1's.

Michael