Bug#944965: debsums: Script accesses internal dpkg database

[Axel Beckert]

Control: clone -1 -2
Control: reassign -2 dpkg
Control: retitle -2 dpkg: Please provide a command-line option to show md5sums for multiple or all packages with one call
Control: submitter -2 !
Control: block -1 by -2

Hi Guillem,

while trying to check what's left to implement this, I got reminded by
this source code comment which currently IMHO very well validates
direct database usage (as you seem to have noticed, too):

    # Calling dpkg-query --control-path for every package is too slow,
    # so we cheat a little bit.

Guillem Jover wrote:
> The debsums program should be switched to use something like:
> 
>   «dpkg-query --control-show $pkg md5sums»
> 
> to get the md5sums file contents. [...] While this is not ideal,
> because this interface does not allow batching, at least it will
> stop accessing the internal database. I will be adding in the near
> future a new virtual field to dpkg-query to be able to fetch all
> md5sums for all packages with something like:
> 
>   «dpkg-query \
>     --showformat 'Package: ${Package}\nMd5sums: ${db-fsys:Md5sums}\n' \
>     --show»

So please do so. Cloning this bug as a reminder and blocker.

Will for now upload debsums with just debsums_init removed, so at
least a bit of this issue is resolved that way.

> The other question though, is whether it still makes sense to ship
> debsums, with «dpkg --audit» checking for missing md5sums files,
> «dpkg --verify» checking for hash mismatches, and «dpkg --unpack»
> generating these when the to be installed does not provide one?

>From my point of view alone the different (IMHO way more comfortable)
command-line user interface and more readable output still validates
it's existence. (I really dislike that rpm format. :-)

I also haven't found an quick and easy way to just show conffiles or
non-conffiles with dpkg --verify on a quick glance. Even to grep out
the just changed ones is not that trivial.

		Regards, Axel
-- 
 ,''`.  |  Axel Beckert <abe at debian.org>, https://people.debian.org/~abe/
: :' :  |  Debian Developer, ftp.ch.debian.org Admin
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