A script for visualizing the package dependency interactions in a Debian metapackage.

visualize-metapackage

#!/bin/bash
#
# Generates graphviz DOT source code from a control file. The graph represents
# the dependency interaction for all binary packages in the control file. Only
# depends are handled right now, recommends and suggests are ignored.

trim_string () {
   sed 's/^[ \t]*//;s/[ \t]*$//'
}

echo_dotcode() {
  package_name="${1:-}";
  readarray -d'|' -t package_list <<< "${package_name}"
  for package in "${package_list[@]}"; do
     real_package="$(trim_string <<< "${package}")"
     echo "  \"${current_package}\" -> \"${real_package}\";"
  done
}

file_name="${1:-}"
[ -z "${file_name}" ] && exit 1

readarray -t file_contents < <(cat "${file_name}")

line_type=''
line_val=''
line_type_is_new='n'
current_package=''

echo 'digraph G {'
echo '  rankdir="LR";'

for line in "${file_contents[@]}"; do
   if [[ "${line}" =~ ^[a-zA-Z]*: ]]; then
      line_type="$(cut -d':' -f1 <<< "${line}")"
      line_type_is_new='y'
   else
      line_type_is_new='n'
   fi  

   if [ "${line_type_is_new}" = 'y' ]; then
      line_val="$(cut -d':' -f2- <<< "${line}" | trim_string)"
   else
      line_val="$(trim_string <<< "${line}")"
   fi  

   if [ "${line_type}" = 'Package' ]; then
      current_package="${line_val}"
      continue
   elif [ "${line_type}" = 'Depends' ]; then
      package_name="${line_val//','}"
      if [[ "${package_name}" =~ [{}] ]]; then
        continue
      fi  
      echo_dotcode "${package_name}"
      continue
   fi  
done

echo '}'