[Pkg-shadow-devel] Bug#269573: First plans to move {add|remove}-shell from passwd to debianutils

[Christian Perrier]

Below is an IRC discussion I (bubulle) had with Nicolas François
(nekral) and Clint Adams (Clint...:-)) about possible ways to deal
with this transition:

19:49  * Clint waves.
19:50 < bubulle> ~thanks for joining, Clint
19:50 < bubulle> In #269573, I proposed you first shoot by uploading debianutils with {add|remove}-shell
19:51 < Clint> with Replaces: on passwd
19:51 < bubulle> conflicting with current version of passwd
19:51 < bubulle> hmmm, Replaces?
19:51 < Clint> yes, I think so
19:52  * bubulle should read doc about Replaces..:-)
19:53 < bubulle> what will happen, then?
19:54 < Clint> the new debianutils will be installed, and dpkg will replace add-shell/remove-shell from passwd
19:54 < Clint> then passwd would need to drop add-shell/remove-shell
19:55 < bubulle> well, but in the meantime, passwd will be removed from the users systems, right?
19:55 < Clint> no, it shouldn't be
19:56 < bubulle> when both packages are Essential, then dpkg will automatically remove the package which is causing the conflict
19:56 < bubulle> from "http://www.debian.org/doc/debian-policy/ch-relationships.html#s-conflicts"
19:56 < Clint> that's why we're not using Conflicts
19:57  * bubulle is obviously missing a point..:-)
19:57 < bubulle> debianutils is Essential, passwd is not
19:57 < Clint> ahh.. yes
19:58 < Clint> passwd may need to declare a dependency of some kind on debianutils
19:58 < bubulle> for instance Depends: debianutils (<< 2.14.3)
19:59 < bubulle> So, when the new debianutils will comme, the system won't upgrade it with this passwd
19:59 < Clint> i'm getting dizzy
20:00 < bubulle> let's summarize what I have in mind
20:00 < bubulle> 1) I upload with "Depends: debianutils (<< 2.14.3)"
20:01 < bubulle> 2) you upload 2.14.4 or 2.15 with the utilities
20:01 < bubulle> 3) I upload passwd without the utilities and without the "Depends"
20:01 < Clint> okay
20:01 < Clint> we'll call it 2.15
20:02 < bubulle> maybe ask for some adive to the release team?
20:02 < Clint> good idea
20:02 < bubulle> In case we would have forgotten something
20:03 < bubulle> what I don't know is what will happen when users will upgrade BOTH packages at the same time *after* the transition
20:03 < nekral> an user may have passwd uploaded by 3), but not debianutils 2.15. Is this an issue?
20:04 < bubulle> nekral: then, (s)he will be missing the utilities, so if some shell is to be added|removed we may end up in a bug
20:05 < bubulle> In 3) we should maybe "Depends: debianutils (>= 2.15)
20:05 < Clint> it may need to be a Pre-Depends, but I forget the factors behind that
20:06 < nekral> Pre-Depends: This is stronger than Depends:. The package will not be installed unless the packages it pre-depends on are installed and correctly configured. Use this very sparingly and only after discussing it on the debian-devel mailing list. Read: don't use it at all. :-)
20:06 < bubulle> nekral: well, in cases we're likely to break the whole system, we maybe can..:-)
20:07 < nekral> Yes, just a cut&paste from the Debian New Maintainers' Guide
20:09 < bubulle> I actually don't see any need for Pre-Depends
20:09 < bubulle> it just requires that the package depended on is fully configured....
20:09 < Clint> yes, that shouldn't be an issue
20:09 < bubulle> in our case, we just need that debianutils is unpacked
20:09 < Clint> right
20:09 < bubulle> so that *-shell stuff is still available
20:11 < bubulle> well, if no more ideas come around, I propose pasting all this in the bug log, then very shortly summarize and ask for advices on -devel (or on IRC #debian-release)
20:12 < Clint> hmm, that should probably be <= 2.14.3
20:12 < bubulle> yes
20:13 < Clint> okay


So, the summary is:

("the utilities" below stands for add-shell and remove-shell)

1) shadow package maintainers upload passwd which 
   "Depends: debianutils (<= 2.14.3)"
   this version *still* includes the utilities   

2) we warn Clint

3) He uploads debianutils 2.15 with the utilities

4) He warns us..:-)

5) We upload passwd *without* the utilities and 
   "Depends: debianutils (>= 2.15)"

6) we might need to later warn maintainers of shell packages which
   maybe depend on passwd just because they need the utilities