Re: Low-level repository inspection (Re: Where do I stick development documentation?)

From: Jonathan Nieder <jrnieder@gmail.com>
Date: Aug 12, 2010, 03:57 UTC
Message-ID: <20100812035733.GA19676@burratino>
In-Reply-To: <AANLkTikpT=PD0Q8d=6=989N6rxYXH-Le3Go_szAz-t4s@mail.gmail.com>

Ævar Arnfjörð Bjarmason wrote:

Show 6 quoted lines

> Those are part of the way there, but you often have to tease info out
> of them, e.g. if you want a commit -> commit roundtrip:
> 
>     $ echo 7980e417 | git cat-file --batch | perl -0777 -pe 's/.*
> commit ([0-9]*).(.*)\n/commit $1\0$2/s'|sha1sum
>     7980e41746bc5de91eea775f9142ce44b1100361  -

hash-object -w (and other “manipulation commands”)?

Show 5 quoted lines

> It'd be nice to answer "how are object stored" with something like:
> 
>     $ echo 7980e417 | git some-thing --pretty=raw -
>     commit <SP> 525 <NULL>
>     tree ....

Part of the reason I mention these interfaces is that if people use them (or something like them --- e.g., JGit) then it becomes a lot easier for low-level details of git to evolve.

That is part of why git uses zlib instead of gzip for its loose objects, if I remember correctly.