[RFC] Build tag in RPM: from NVR to NVRB

[Aleksandra Fedorova]

Hi, all,

I'd like to discuss how we can add Build tag in the RPM.

As one of the key points is to turn it into a common standard for rpm
packages across the ecosystem, the conversation is currently opened
upstream [1] and in RHEL Engineering. And I'd like to get Fedora
community on board.

This is not a finalized proposal and I think it is not ready yet to be
a Fedora Change.
But I want to start a conversation and ask for opinions. There are
also some open questions which need help, especially the requirements
around build reason. And alternative suggestions are welcome as well.

I've posted long version at
  https://discussion.fedoraproject.org/t/rfc-build-tag-in-rpms/39954

You can comment there (simply login with your FAS id) or here on the
mailing list.
And I am going to update that post with the new feedback.

Shorter version:
================================================
We'd like to introduce Build Number/Tag/Id in the rpm metadata.

By this change we would like to:
* Provide a possibility to change build environment and rebuild rpm
packages without changing their content: neither sources nor spec
files.
* Set a common standard for the RPM-based ecosystem, which can be used
not just within Fedora, but also by Remixes, downstreams, SIGs and
other distributions.

The most visible impact of the proposal would be the filename change:

  Current: dnf-4.9.0-12.fc36.noarch.rpm
  Proposed: dnf-4.9.0-12.fc36.34897715.noarch.rpm

It can be implemented in two steps:

1) Now → Compatibility mode

* Introduce Build tag in the rpm metadata
* Introduce “build reason” to be added to rpm changelog as a top entry
* Enable passing Build tag value to the build in Koji. The value of
the Build tag will be set from Koji build id.
* Introduce macro in Release field of the rpm spec files, which adds
Build tag after the usual disttag
    Release: 12.%{?dist}%{?build:.%{build}}
* Introduce option to pass “build reason” to a Koji build via koji cli
and fedpkg/centpkg tooling.

2) Compatibility mode → Final

* Implement support for the upgrade path on the rpm side in a
compatible way. So that NV(R’=R+B) and NVRB are treated the same.
* Remove %{build} part from Release tag and use independent Build tag
for versioning.
================================================

[1] https://github.com/rpm-software-management/rpm/discussions/2031

-- 
Aleksandra Fedorova
CI for Fedora/CentOS Stream/RHEL
bookwar on Matrix/IRC