Re: [3/5] Add http-pull

[Petr Baudis <pasky@ucw.cz>]

Dear diary, on Fri, Apr 22, 2005 at 09:46:35PM CEST, I got a letter
where Daniel Barkalow <barkalow@iabervon.org> told me that...
> On Thu, 21 Apr 2005 tony.luck@intel.com wrote:
> 
> > On Wed, 20 Apr 2005, Brad Roberts wrote:
> > > How about fetching in the inverse order.  Ie, deepest parents up towards
> > > current.  With that method the repository is always self consistent, even
> > > if not yet current.
> > 
> > Daniel Barkalow replied:
> > > You don't know the deepest parents to fetch until you've read everything
> > > more recent, since the history you'd have to walk is the history you're
> > > downloading.
> > 
> > You "just" need to defer adding tree/commit objects to the repository until
> > after you have inserted all objects on which they depend.  That's what my
> > "wget" based version does ... it's very crude, in that it loads all tree
> > & commit objects into a temporary repository (.gittmp) ... since you can
> > only use "cat-file" and "ls-tree" on things if they live in objects/xx/xxx..xxx
> > The blobs can go directly into the real repo (but to be really safe you'd
> > have to ensure that the whole blob had been pulled from the network before
> > inserting it ... it's probably a good move to validate everything that you
> > pull from the outside world too).
> 
> The problem with this general scheme is that it means that you have to
> start over if something goes wrong, rather than resuming from where you
> left off (and being able to use what you got until then).

Huh. Why? You just go back to history until you find a commit you
already have. If you did it the way as Tony described, if you have that
commit, you can be sure that you have everything it depends on too.

-- 
				Petr "Pasky" Baudis
Stuff: http://pasky.or.cz/
C++: an octopus made by nailing extra legs onto a dog. -- Steve Taylor