Adding YAML front matter to markdown files (title)

Prepend YAML Front Matter to Markdown Files

# For each result of find call our script to run on the filename
$ find . -name "*.md" -print0 | xargs -0 -I file ./prepend.sh file

prepend.sh

# Given a file path as an argument
# 1. get the file name
# 2. prepend template string to the top of the source file
# 3. resave original source file

filepath="$1"
file_name=$(basename $filepath)

# Getting the file name (title)
md='.md'
title=${file_name%$md}

# Prepend front-matter to files
TEMPLATE="---
layout: page
title: $title
category: gen
---

"

echo "$TEMPLATE" | cat - "$filepath" > temp && mv temp "$filepath"

Thank you for you code!
I use this command line "find . -name "*.md" -print0 | xargs -0 -I file ./prepend.sh file"
and it noticed me this:
"xargs: ./prepend.sh: Permission denied"

Could you help me?