[EPEL-devel] Rules for shadowing RHEL packages with EPEL modules

[Petr Pisar]

If I read the EPEL 8 annoucement correctly, it's still not possible to build
modules in EPEL. Nevertheless I'd like to know how the rules about "not
replacing RHEL content" will apply to modules. Here are my question:

Case: RHEL delivers an M module with a default S1 stream. There is no S2
stream. Can I add a new S2 stream into EPEL? I guess this will be allowed. If
later RHEL introduces S2 stream, I guess EPEL will remove the S2 module.

Case: RHEL delivers an M module with no default stream, there is no S stream.
Can I add a new S stream into EPEL and make it default? I'm not sure this will
be allowed. There is a risk of creating conflicts between streams transitively
required by another default streams. (Remember the libgit2 module conflict
<https://bugzilla.redhat.com/show_bug.cgi?id=1717117>.)

Case: RHEL delivers a non-modular P package. There is no S stream of
a M module. Can I add a new M module with a new S stream that will contain
a modular P package? I guess it will be allowed. Can I make the stream
default? I guess that won't be allowed.

Case: RHEL delivers a P package. Can I build a modular P package when building 
a new module stream in EPEL only for the purpose of building the module
and then filter out the P package from the module (i.e. a build-only module
component) so that the P package does not get into EPEL repository? I guess
this will be allowed.

Could EPEL product owner (or whoever makes and assert the rules) clarify?
I need to know that to choose the easiest and yet conforming strategy for
adding new modules into EPEL, especially when dealing with RHEL packages
unavailable for some module contexts.

-- Petr