RFE: Add a way to return whether a module build requires or requires a particular platform

[mohanboddu]

As part of mass rebuild we need to know what modules should be rebuilt and that can be identified by looking at the the modulemd build requires, it would be easy if libmodulemd can provide that info when a modulemd with a platform is provided.

Same as above but during branching, we need to identify the modules that runtime requires a certain platform. So, when a modulemd is provided with a platform, please return whether the platform is a runtime requirement or not.

[sgallagher]

@mohanboddu Would an API like this work?

#!/usr/bin/python3

import gi
gi.require_version('Modulemd', '2.0')
from gi.repository import Modulemd

index = Modulemd.ModuleIndex.new()
index.update_from_file('./modules.yaml', False)

modules_to_build = index.get_modules_that_build_depend_on_stream ('platform', '31')

The modules_to_build would be a list of Modulemd.ModuleStream objects that matched the provided module and stream in buildrequires. The same would be offered for requires also (as index.get_modules_that_depend_on_stream ('platform', '31'))

Also pinging @puiterwijk for his opinion.

I think I'll publish this as Stability: unstable for now.

[sgallagher]

@mohanboddu In the specific case of the mass-rebuild that we discussed in-person yesterday, you'd create a new index for each yaml document in the dist-git repos and then you could just check size(modules_to_build) to determine if that build should be included (since there would only be one module in the index, so either it will or won't be returned).

[mohanboddu]

@mohanboddu Would an API like this work?

#!/usr/bin/python3

import gi
gi.require_version('Modulemd', '2.0')
from gi.repository import Modulemd

index = Modulemd.ModuleIndex.new()
index.update_from_file('./modules.yaml', False)

modules_to_build = index.get_modules_that_build_depend_on_stream ('platform', '31')

The modules_to_build would be a list of Modulemd.ModuleStream objects that matched the provided module and stream in buildrequires. The same would be offered for requires also (as index.get_modules_that_depend_on_stream ('platform', '31'))

Also pinging @puiterwijk for his opinion.

I think I'll publish this as Stability: unstable for now.

@sgallagher I think it will work.

Thanks.

[sgallagher]

@mohanboddu While implementing, I've realized that the above approach won't work (mostly because the contents in dist-git have no name or version fields, because that's populated by MBS from the dist-git repo and branch. The new approach looks like this:

import gi
gi.require_version('Modulemd', '2.0')
from gi.repository import Modulemd
stream = Modulemd.ModuleStream.read_file('something.yaml', True)

# Run-time requires
stream.depends_on_stream('platform', 'f30')

# Build-time requires
stream.build_depends_on_stream('platform', 'f30')

[mohanboddu]

@sgallagher That should work.

Thanks.

[sgallagher]

@mohanboddu I've pushed the fix and build libmodulemd 2.1.0 for Rawhide, F29 and F28. You can see the API documentation for the new functions at https://sgallagh.fedorapeople.org/docs/libmodulemd/2.0/modulemd-2.0-ModulemdModuleStream.html#modulemd-module-stream-depends-on-stream

[mohanboddu]

@sgallagher awesome, thanks for your help.