[Rpm-ecosystem] Some points about zchunk

[Michael Schroeder]

On Wed, Jul 11, 2018 at 11:20:00AM +0100, Jonathan Dieter wrote:
> I must be missing something because I don't understand how that
> follows.  As I understand it, dnf requests the primary metadata. 
> Librepo then downloads either primary.xml.gz or primary.xml.zck. 
> Librepo then asks libsolv to decompress the xml file and convert it
> into a solv file.  dnf then uses the solv file directly.  Why should
> dnf care whether librepo downloaded primary.xml.gz or primary.xml.zck?

But it's not librepo that calls libsolv, it's libdnf.

Anyway, this discussion started because you said:

> I had originally planned to do something along these lines (I think I
> used primary-zck rather than primary at zchunk), but realized that this
> pushed the "choose best format" code into the top-level tools, rather
> than leaving the decision in librepo.

So you're kind of contradicting yourself, IMHO.

Basically all libdnf does is call:
  path = lr_yum_repo_path(yum_repo, "primary");
and then:
  fp_primary = solv_xfopen(hy_repo_get_string(hrepo, path);
  repo_add_rpmmd(repo, fp_primary, 0, 0);

I don't see why librepo can't automagically download/return the
"primary at zchunk" entry instead of "primary".

Cheers,
  Michael.

-- 
Michael Schroeder                                   mls at suse.de
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