mkosi.preflight script support #4056
Description
Hello there,
I know this has already been talked about a little bit in #3176 but i was wondering if you would accept a patch for this kind of system.
The main usage i was thinking about is downloading packages or artifacts from elsewhere before running mkosi.
For example, download kernel packages that has been built elsewhere and are in some kind of artifacts repository, put them in mkosi.profiles/some_profile/mkosi.packages and writing the necessary config file to install them in mkosi.profiles/some_profile/mkosi.conf.d/99-generated-kernel.conf
This could also be used to download binaries inside the skeleton (IE static binaries that do no have any kind of packages) before building the actual images.
I was mainly thinking of that so it avoids having to setup special scripting around mkosi or in a sort of ci pipeline that wrapps around mkosi, or avoid the burden of having to setup a specific package repository that would contain those.
Right now, i have a script that wrapps mkosi, checks if before building a profile if there is prefligh.sh scripts inside the profile, and if yes, chdir to the profile directory and executes it.
Kind regards,
An happy mkosi user.