= BuildRequires Generators =
== Summary ==
Add possibility to generate build-time dependencies within RPM spec
file and teach RPM and mock how to handle this.
== Owner ==
* Name: [[User:ignatenkobrain|Igor Gnatenko]], [[User:ffesti|Florian
Festi]], [[User:msuchy|Miroslav Suchý]]
* Email: ignatenkobrain(a)fedoraproject.org, ffesti(a)redhat.com, miroslav(a)suchy.cz
== Detailed Description ==
For many languages (Rust, Golang, Node.Js, Ruby, Python),
BuildRequires can be automatically generated. All it takes, run some
special tool which will output dependencies in RPM format.
Q: How will it work under the hood?
A: When you build RPM, something like this will happen under the hood…
# rpm would perform %prep (which is supposed to abort if some
dependencies missing and print them)
# mock would install those dependencies and resume build
Q: Will src.rpm contain all generated dependencies?
A: This is not known yet, we'll update page once it is known.
Q: Does this mean that package builds won't be reproducible anymore?
A: No, as long as you have same buildroot and tool which is generating
BuildRequires is doing so in reproducible manner, it should not affect
== Benefit to Fedora ==
Packagers won't have to pre-generate BuildRequires in the spec file
which means it will be always updated (and correct) :
* Packagers can focus of making their packages better instead of
spending all their packaging time copying BuildRequires from
documentation and third party tools.
* BuildRequires are dropped as soon as they're no longer necessary
* Packages can be easily bumped without requiring a manual BuildRequires refresh
* BuildRequires and Requires generation can use similar utilities,
making sure that the deps packages declare can also be used for
second-level building. Packages no longer need to declare the deps of
their second and n-th dependencies because someone forgot to declare
them in the correct package.
== Scope ==
* Proposal owners: Implement support for a feature in RPM and mock (if
implemented properly, Koji should just work). Make use of it in Rust
* Other developers: Maintainers of language stacks are advised to use
* Release engineering: [https://pagure.io/releng/issue/8129
* Policies and guidelines: Packaging Guidelines need to be updated
with instructions how to use this feature.
* Trademark approval: N/A (not needed for this Change)
== Upgrade/compatibility impact ==
Packagers and users who use repoquery might be affected (src.rpm might
not contain generated dependencies).
== How To Test ==
== User Experience ==
Users won't notice differences.
== Dependencies ==
Required feature needs to be implemented in RPM and mock.
== Contingency Plan ==
* Contingency mechanism: (What to do? Who will do it?) Proposal
Owners might still ship feature disabled for Fedora buildsystem but
have it available for end-users, and move full completion to the next
* Contingency deadline: Beta Freeze
* Blocks release? No.
* Blocks product? No.
== Documentation ==
== Release Notes ==
Fedora Program Manager