uuid-line-fill

exec ruby -p "$0" "$@"
#!ruby -p

###
# uuid-filler reads input lines and fills in secure random UUIDs.
#
# This looks for the text "uuid:" on a line by itself, 
# and appends a secure random UUID in quotation marks.
#
# Example:
#   cat foo.txt | uuid-filler > foo-with-uuid-filled-in.txt
#
# Example input:
#   foo
#   uuid:
#   goo
#   uuid:
#   hoo
#
# Example output:
#   foo
#   uuid: "73443f62-c068-4e7d-93a1-716d3ce295e0"
#   goo
#   uuid: "b83f5d15-2fb1-4a8a-9329-5d4c2326aebf"
#   hoo
#
# Details on the "uuid:" text:
#   - Must be on a line by itself.
#   - Matching is case insensitive.
#   - Leading whitespace is preserved.

BEGIN {
 require 'securerandom'
}

$_.sub!(/^(\s*\buuid:)\s*\n/i, '\1 ' + '"' + SecureRandom.uuid + '"' + "\n")