Recursive package dependency removal tool for kisslinux

kiss-rmdeps

#!/bin/sh -e
# Interactively and recursively remove packages with dependencies

# Check if terminal is interactive
[ -t 1 ] || {
  echo "error: launched in non-interactive environment";
  exit 1;
}

# Check if all given packages are installed
[ "$*" ] && kiss list "$@" >/dev/null || {
  echo "usage: [kiss-rmdeps [pkg]...]";
  exit 1;
}

# Conditionally use sexy kiss-accurate colors for prompts
if [ "$KISS_COLOR" != "0" ]; then
  col0="$(printf "\033[m")";
  col1="$(printf "\033[1;33m")";
  col2="$(printf "\033[1;34m")";
else
  col0="";
  col1="";
  col2="";
fi;
prompt="${col1}->${col0}";

# Check if $1 is an item in space-separated list $2
is_item() {
  case "$2" in
    "$1"|"$1 "*|*" $1 "*|*" $1")
      return 0;
    ;;
  esac;
  return 1;
}

cd "$KISS_ROOT/var/db/kiss/installed";

# List of packages explicitly marked for keeping
keep="";

count=0;

# Keep looping until we stop marking new items to be removed (in $@)
while [ "$#" != "$count" ]; do

  count="$#";

  # Find all of the dependencies of explicitly marked packages
  # They are all candidates for removal
  deps="$(
    for pkg in "$@"; do
      cat "./$pkg/depends" 2>/dev/null;
    done | awk '{ print $1 }' | sort -u | grep -v "#" || true;
  )";

  for pkg in $deps; do

    # Check if candidate has been marked for removal already
    is_item "$pkg" "$*" && continue;

    # Check if candidate has been marked for keeping already
    is_item "$pkg" "$keep" && continue;

    # Find all dependants of the candidate
    dependant="";
    for revdep in $(grep "^$pkg" -- ./*/depends | awk '{ print $1 }'); do
      # Strip grep candy
      revdep="${revdep##./}";
      revdep="${revdep%%/depends*}";
      # Check if dependant is also marked for removal
      is_item "$revdep" "$*" || {
        dependant="yes";
        break;
      }
    done;
    # If depended on by packages not being removed, can't mark for removal
    # But don't explicitly mark for keeping either
    # The dependants that retain it may themselves be marked for removal later
    [ "$dependant" = "yes" ] && continue;

    # We ignore a missing package
    # Could be a maketime dep or a broken tree
    # Either way, we don't want kiss to error out in between
    kiss list "$pkg" >/dev/null 2>/dev/null || continue;

    # The candidate will be orphaned when everything marked until now is removed
    # So it is possible to remove it
    # But it may be a package the user actually needs (a user-facing package)
    # Ask the only one who really knows: the user
    echo;
    printf "${prompt} ${col2}${pkg}${col0} mark for removal?: [y/n] ";
    read -r REPLY;
    case $REPLY in
      Y*|y*)
        # Decisive yes, mark candidate for removal
        set -- "$@" "$pkg";
        continue;
      ;;
      N*|n*)
        # Decisive no, mark candidate for keeping
        keep="$keep $pkg";
        continue;
      ;;
    esac;

    # Ambiguous answer from user, possible auto decision mechanisms go here
    # They can make a decisive decision
    # We should generally avoid making a removal decision automatically
    # The condition could be, for example, to keep everything except libs
    # (case "$pkg" in lib*) false ;; *) true ;; esac;)
#    if BOT_SAYS_DEFINITELY_NO; then
#      echo;
#      echo "${prompt} ${col2}${pkg}${col0} marking for keeping (auto)";
#      keep="$keep $pkg";
#      continue;
#    elif BOT_SAYS_DEFINITELY_YES; then
#      echo;
#      echo "${prompt} ${col2}${pkg}${col0} marking for removal (auto)";
#      set -- "$@" "$pkg";
#      continue;
#    fi;

    # Consider reaching this point undecided as a decisive no, mark for keeping
    keep="$keep $pkg";

  done;

done;

# Show the user the result and give a chance to abort
echo;
echo "${prompt} Removing: ${col2}$*${col0}";
echo;
echo "${prompt} Continue?: Press Enter to continue or Ctrl+C to abort here";
read -r REPLY;

# Run kiss remove
echo kiss remove "$@";

Simply run it with one or more orphans as arguments, and it will show you an interactive y/n prompt for removing every package that would become an orphan once the given packages are removed, and then descends recursively for packages you've selected out of those.

At the end, it will give you a single kiss remove command to uninstall everything you've chosen to remove (remove echo from the last line if you actually want it to execute the command and not just give you one to copy.)

Just a fun idea I had while reading the FAQ. It just automates the loop of reading kiss orphans and running kiss remove over and over, without actually removing anything and just giving you a single command to do everything in the end.

It makes no decisions on its own and the user still decides which of those packages need to be kept (though you can add conditional logic for making keep/remove decisions automatically, see comments).