test_what_non_el_remains_after_migration.sh

#!/bin/bash

usage() {
    echo "Usage: ${0##*/} [OPTIONS]"
    echo
    echo "OPTIONS"
    echo "-t      Tolerate packages from 3rd-party repos, e.g. from EPEL"
    exit 1
}

tolerance=""

while getopts "t" option; do
    case "$option" in
        t) tolerance="tolerate-thirdparty" ;;
        *) usage ;;
    esac
done

echo "Performing post-migration checks..."
mapfile -t non_eurolinux_rpms_from_yum_list < <(yum list installed | sed '/^[^@]*$/{N;s/\n//}' | grep -Ev '@el-server-|@euroman|@fbi|@certify' | grep '@' | cut -d' ' -f 1 | cut -d'.' -f 1)
  mapfile -t non_eurolinux_rpms_and_metadata < <(rpm -qa --qf "%{NEVRA}|%{VENDOR}|%{PACKAGER}\n" ${non_eurolinux_rpms_from_yum_list[*]} | grep -Ev 'EuroLinux|Scientific' | sed 's@\ @\_@g' | grep -Ev '^(rhnlib|rhnsd).+\|\(none\)\|\(none\)$') 
if [[ -n "${non_eurolinux_rpms_and_metadata[*]}" ]]; then
  echo "The following non-EuroLinux RPMs are installed on the system:"
  printf '\t%s\n' "${non_eurolinux_rpms_and_metadata[@]}"
  if [ "$tolerance" == "tolerate-thirdparty" ]; then # Tolerate packages e.g. from EPEL, do not tolerate from AlmaLinux/CentOS/Oracle Linux/RHEL/Rocky Linux.
    echo "Checking for the presence of packages that come from the migratable systems..."
    bad_providers_pattern="\|AlmaLinux\||\|CentOS\||\|Oracle_America\||\|Red_Hat,_Inc\.\||\|Rocky\|"
    if grep -E "$bad_providers_pattern" <<< "${non_eurolinux_rpms_and_metadata[@]}" ; then
      echo "^ the packages above still remain - the migration is not considered as 100% complete. Please remove them manually."
      exit 1
    else
      echo "(none, the migration removed all packages from migratable systems)"
      exit 0
    fi
  else
    echo "Since the test requires that no thirdparty packages be present on the system, we consider this result as a failure."
    exit 1
  fi
fi
echo "Success - no non-EuroLinux RPMs are installed on the system."
exit 0