MayBe I …(can do something useful)?

Hello,

We've been discussing some (hopefully) nice idea with Mikolaj, Neal and Jakub how we could improve packager (and user) experience and we have some proposal which will be described below.

We would like to ask you to read it, understand it and ask us any questions you have. From the Fedora Infrastructure we would like to ask for some machines to implement this idea (you can find some more information in "Implementation details" part).

I would like to apologize for HTML email, but it is much easier to have it that way to have better visibility and reading easiness.

Feel free to reply to this email or comment in google doc (there is a link on the bottom). Proposal Owners

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Mikolaj Izdebski (mizdebsk) mizdebsk@redhat.com - Java SIG, Fedora infrastructure -

Igor Gnatenko (ignatenkobrain) ignatenkobrain@fedoraproject.org - Rust SIG, Golang SIG, Neuro SIG, RPM and libsolv contributor -

Neal Gompa (ngompa) ngompa13@gmail.com - Rust SIG, Golang SIG, RPM contributor -

Jakub Čajka (jcajka) jcajka@fedoraproject.org - Golang SIG, Container SIG

This proposal aligns with the objective of improving the packager experience https://fedoraproject.org/wiki/Objectives/Packager_Experience by developing a platform whereby the proposal owners and others can experiment with improvements that can be funneled back into the official production infrastructure. ProblemsProblem №1: Build-only packages

Some ecosystems have many build-only packages (packages which are used to build other packages, without having them installed on end-user systems). Those ecosystems include Java, Rust and Go.

It is extremely hard to keep up maintaining them due to lack of time/people. Upstreams are usually changing quickly (sometimes when you update just one such package, you’d need to update tens of the dependencies). Few facts about such packages:

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They are almost always outdated in released versions of distribution; -

They are often FTBFS (e.g. because there was compiler update but not package update, broken deps, broken APIs due to deps rebases, …).

In Rust ecosystem, we abuse Rawhide to build and store such packages there and then generate end-user application (e.g. ripgrep) which uses some of those packages and produces binary for all supported releases. Those applications have high quality and are supported.

Rawhide gating makes this much more complicated because builds appear in buildroot slower, updating group of packages would need side tags and it’s just painful to work with.

https://pagure.io/fesco/issue/2068

And, after all, those packages shouldn’t be shipped to users. Problem №2: Testing of new rpm/koji/mock features/configuration

When developing new features in RPM (e.g. rich dependencies) or testing different Koji configuration (e.g. removing gcc/gcc-c++ from the buildroot), it is required to make custom configuration and try building things. Problem №3: Developing modules

Modules are built in MBS as a single unit. It is hard to develop big modules by progressively improving individual packages or small package groups. Scratch builds for modules are not implemented. Local builds work differently from official module builds, they don’t scale and don’t allow groups of people to work collaboratively. All these problems can be solved by first developing a flat repository of packages in a shared environment and then generating modulemd from such package set. Problem №4: Testing things before push

Primary Fedora Koji and dist-git are not suited for packaging experimentation. Packagers are expected to experiment on their own systems and push changes of successful experiments only. But this approach doesn’t scale with number of maintained packages. Often you can find commits like “d’oh, forgot to upload sources” or “let’s try with this settings”. People need to build things somewhere quickly, do development and testing. And only after that, they should push commit(s) to Fedora. Solution

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Separate Koji + Koschei deployed in Fedora infrastructure cloud; -

Builders are optimized for the best performance (see below https://docs.google.com/document/d/1DtNTCa-gXc0ILDDHPyAcAca2GGGlENavfgPwGGgqJ_Y/edit#heading=h.amk0udnj85tg ); -

People can have their own targets where they can break things as they wish without affecting others; -

Package changes are eventually contributed to Fedora proper by merging changes to Fedora dist-git and rebuilding packages in official Fedora Koji; -

All improvements can eventually be contributed back to official Fedora infra.

Ideas

All ideas which you’ll find below are just an ideas and do not have to be implemented. Idea №1: Automated legal review

openSUSE released their review app called Cavil https://github.com/openSUSE/cavil which we could try running in automated way. Idea №2: Automated package review

Currently review process is burden and we could run automated legal review, create a repo, run set of checks and notify person. Somewhat similar to fresque https://github.com/fedora-infra/fresque. In future might be integrated with approval process and auto-imported into Fedora. Idea №3: Building packages for multiple distributions

In Rust ecosystem, we managed to get have same packaging guidelines in openSUSE, Mageia and Fedora. We could automatically build some packages on multiple distributions and be kinda upstream. Idea №4: Building custom images with user content

Deploy (or build) a tool(s) to enable user-built install, appliance and container images with their content (modulo restrictions similar to COPR) on top of Fedora. Implementation details

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Koji and Koschei deployed in fedorainfracloud.org -

A few builders constantly running, with a possibility to add more builders as needed and as available cloud resources allow -

Deployed and maintained by proposal owners - not supported by Fedora infrastructure -

Other contributors can have access granted by proposal owners (for the time being only users in “packagers” group will be eligible to get access) -

Possibility to have some builders running outsides of Fedora infrastructure - contributed by proposal owners -

Koji builds can be done from SCM (src.fp.o, pagure.io, github, …) or from SRPM upload

FAQWhy not COPR?

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COPR has been starved of resources for years, which has impaired its ability to provide reliable service at scale. Fedora Infrastructure refuses to consider supporting it officially and Fedora Release Engineering seems to have some undefined issues with COPR. -

It is not official build system of Fedora which is not helping with Problem №2: Testing of new rpm/koji/mock features/configuration https://docs.google.com/document/d/1DtNTCa-gXc0ILDDHPyAcAca2GGGlENavfgPwGGgqJ_Y/edit#heading=h.iodoq4xw80c2 . -

COPR is not extensible enough, more specifically: -

No query API (e.g. it is not possible to find out from which SCM commit the package has been built) -

Builds always have access to all previous builds in a repository (i.e. not possible to control when/how repo is created) -

GC doesn’t exist -

No scratch builds

Why not staging Koji?

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Staging Koji is meant for testing Koji itself and not for package development. -

Staging Koji is often in broken state where it is not possible to build anything. -

No one can touch staging Koji, so it’s pointless for offering a useful service.

How can you make Koji builds faster?

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By tuning Koji for performance, not correctness and reliability. -

By building only on a single, fast architecture. -

By extensive caching. Files like RPM packages, repodata and files in lookaside cache don’t change after they are initially stored, so builders can cache them aggressively. -

By keeping build repositories small. Some package sets don’t need to be built against full Fedora, but can use a minimal subset of Fedora. Such repositories can be generated by Koji in seconds, not minutes.

Why not the Open Build Service (OBS)?

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OBS is not yet packaged for Fedora officially. The upstream code lacks adaptations necessary to deploy and run on Fedora and in Fedora Infrastructure. -

OBS is not official build system of Fedora, which does not help with Problem №2: Testing of new rpm/koji/mock features/configuration https://docs.google.com/document/d/1DtNTCa-gXc0ILDDHPyAcAca2GGGlENavfgPwGGgqJ_Y/edit#heading=h.iodoq4xw80c2 .

What does MBI stand for?

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M for middlestream, module, mizdebsk, … -

B for build, bootstrap, … -

I for infrastructure, initiative, ignatenkobrain, … -

MBI might be pronounced as “maybe I …(can make something cool)?” -

MBI is also initials of mizdebsk (Mikolaj Bozydar Izdebski) -

MBI is also IBM spelled backwards :)

Is it somehow related to Fedora Playground https://fedoraproject.org/wiki/Playground?

Yes, it is. Although it is more developer-focused. Users could enrol for some specific things like experimental Java/Rust packages.

MBI (Playground 2.0) https://docs.google.com/document/d/1DtNTCa-gXc0ILDDHPyAcAca2GGGlENavfgPwGGgqJ_Y/edit?usp=drive_web