blog

Bez Hermoso, Software Engineer @ Square

Protip: warn about file changes, deletions & additions before rsync

23 Jun 2016

I wrote a shell script that wraps rsync with a user prompt in cases where files are going to be added, deleted, or changed, which is a scenario when some work might get lost:

safe-rsync.sh:

#!/usr/bin/env bash

args=$@

diffs="$(rsync --dry-run --itemize-changes $args | grep '^[><ch.][dfLDS]\|^\*deleting')"

if [ -z "$diffs" ]; then
  echo "Nothing to sync."
  exit 0
fi

echo "These are the differences detected during dry-run. You might lose work. Please review before proceeding:"
echo "$diffs"
echo ""
read -p "Confirm? (y/N): " choice

case "$choice" in
  y|Y ) rsync $args;;
  * ) echo "Cancelled.";;
esac

Usage

> ./safe-rsync.sh --exclude='node_modules/' --recursive --progress --verbose ubuntu@aws-server102:/var/www/html ./html

To skip the dry-run and just rsync regardless of any diffs:

> yes | ./safe-rsync.sh --exclude='node_modules/' --recursive --progress --verbose ubuntu@aws-server102:/var/www/html ./html