Parsing INI files in bash - taken from https://blog.sleeplessbeastie.eu/2019/11/11/how-to-parse-ini-configuration-file-using-bash/

README.txt

This is the same as https://blog.sleeplessbeastie.eu/2019/11/11/how-to-parse-ini-configuration-file-using-bash/ except
that it also handles section names with minus ('-').

example.ini

[main]
description = Sample configuration
timeout = 10
monitoring_interval = 20

[database-fubar]
server = db.example.org
port = 3306
username = dbuser
password = dbpass

[monitor-another-minus]
servers[] = www.example.org
servers[] = proxy.example.org
servers[] = cache.example.org
servers[] = bastion.example.org

Example_Output

prompt> ./parse.sh example.ini
Configuration description: Sample configuration

[database-fubar]
  port = 3306 (access it using ${configuration_database_fubar[port]})
  password = dbpass (access it using ${configuration_database_fubar[password]})
  server = db.example.org (access it using ${configuration_database_fubar[server]})
  username = dbuser (access it using ${configuration_database_fubar[username]})
[monitor-another-minus]
  servers = www.example.org proxy.example.org cache.example.org bastion.example.org (access it using ${configuration_monitor_another_minus[servers]})
[main]
  timeout = 10 (access it using ${configuration_main[timeout]})
  description = Sample configuration (access it using ${configuration_main[description]})
  monitoring_interval = 20 (access it using ${configuration_main[monitoring_interval]})

parse.sh

#!/bin/bash

# Read and parse simple INI file

# Get INI section
ReadINISections(){
  local filename="$1"
  gawk '{ if ($1 ~ /^\[/) section=tolower(gensub(/\[(.+)\]/,"\\1",1,$1)); configuration[section]=1 } END {for (key in configuration) { print key} }' ${filename}
}

# Get/Set all INI sections
GetINISections(){
  local filename="$1"

  sections="$(ReadINISections $filename)"
  for section in $sections; do
    array_name="configuration_${section//-/_}"
    declare -g -A ${array_name}
  done
  eval $(gawk -F= '{
                    if ($1 ~ /^\[/)
                      section=tolower(gensub(/\[(.+)\]/,"\\1",1,$1))
                    else if ($1 !~ /^$/ && $1 !~ /^;/) {
                      gsub(/^[ \t]+|[ \t]+$/, "", $1);
                      gsub(/[\[\]]/, "", $1);
                      gsub(/^[ \t]+|[ \t]+$/, "", $2);
                      if (configuration[section][$1] == "")
                        configuration[section][$1]=$2
                      else
                        configuration[section][$1]=configuration[section][$1]" "$2}
                    }
                    END {
                      for (section in configuration)
                        for (key in configuration[section]) {
                          section_name = section
                          gsub( "-", "_", section_name)
                          print "configuration_" section_name "[\""key"\"]=\""configuration[section][key]"\";"
                        }
                    }' ${filename}
        )


}

if [ "$#" -eq "1" ] && [ -f "$1" ]; then
  filename="$1"
  GetINISections "$filename"

  echo -n "Configuration description: "
  if [ -n "${configuration_main["description"]}" ]; then
    echo "${configuration_main["description"]}"
  else
    echo "missing"
  fi
  echo

  for section in $(ReadINISections "${filename}"); do
    echo "[${section}]"
    for key in $(eval echo $\{'!'configuration_${section//-/_}[@]\}); do
        echo -e "  ${key} = $(eval echo $\{configuration_${section//-/_}[$key]\}) (access it using $(echo $\{configuration_${section//-/_}[$key]\}))"
    done
  done
else
  echo "missing INI file"
fi