Parse YAML using pure Bash

parse_yaml.sh

# bash-only parser that leverages sed and awk to parse simple yaml files
#
# See https://stackoverflow.com/a/21189044/31493 for usage, caveats, etc.

function parse_yaml {
  local prefix=$2
  local s='[[:space:]]*' w='[a-zA-Z0-9_]*' fs=$(echo @|tr @ '\034')
  sed -ne "s|^\($s\):|\1|" \
     -e "s|^\($s\)\($w\)$s:$s[\"']\(.*\)[\"']$s\$|\1$fs\2$fs\3|p" \
     -e "s|^\($s\)\($w\)$s:$s\(.*\)$s\$|\1$fs\2$fs\3|p"  $1 |
  awk -F$fs '{
    indent = length($1)/2;
    vname[indent] = $2;
    for (i in vname) {if (i > indent) {delete vname[i]}}
    if (length($3) > 0) {
      vn=""; for (i=0; i<indent; i++) {vn=(vn)(vname[i])("_")}
      printf("%s%s%s=\"%s\"\n", "'$prefix'",vn, $2, $3);
    }
  }'
}