Add support for RedHat containers

[faangbait]

Issue: Guidance from Red Hat for containerized development recommends images without yum installed.

From https://access.redhat.com/solutions/3144031:

The rhel-atomic / rhel7-atomic / rhel7/rhel-atomic container image uses microdnf instead of yum for package management. More information about using microdnf can be found in the Getting Started with Containers guide at: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux_atomic_host/7/html/getting_started_with_containers/using_red_hat_universal_base_images_standard_minimal_and_runtimes#add_software_to_a_running_ubi_container

Workaround: curl -fsSL https://rpm.nodesource.com/setup_16.x | sed 's/yum/microdnf/g' | bash -

Solution: Check which package manager exists on the system.

[tukusejssirs]

The fix is quite easy:

1. Define (global) variables (variable names might be changed):

# Note: We could even add a check for `dnf` and change the order of checks.
# Note: First existing program will be used.
PKG_MAN="$(command -v yum || command -v microdnf)"
PKG_MAN_NAME="$(basename "$PKG_MAN")"

2. Change these stuff in rpm/setup*.sh files:
   • keep /etc/yum.repos.d as is;
   • replace all yum strings with $PKG_MAN_NAME;
   • replace all yum commands with $PKG_MAN.

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Now, I could create a PR for this, however, I have no idea if it is enough to make these changes in rpm/src/_setup.sh?

Any guidance apreciated. Or anyone could fix this issue instead of me. :wink: :pray:

[JesusPaz]

This issue is resolved with our new repository. More information can be found here.

[mb-shorai]

@JesusPaz the link points to a non-existent page