example of a hook to automagically deploy a Rails app

post-receive

#!/bin/bash
source $HOME/.bash_profile

APP_NAME="scopi"
APP_PATH=/home/scopi/apps/${APP_NAME}

# Production environment
export RAILS_ENV="production"

exit_with_error() {
  echo "[DEPLOY] !!!!!!!!!!!!!!!!!!!! An error has occurred !!!!!!!!!!!!!!!!!!!!!!!"
  exit 1
}
while read oldrev newrev ref
do
  branch=`echo $ref | cut -d/ -f3`
	# Initial directory is .git, so go to the working copy directory
	cd ${APP_PATH}

	echo "**********************************************************************"
	echo "                      Deploying application...                        "
	echo "**********************************************************************"

	# Add everything to the index and then reset hard to both sweep changed files 
	# (like cached pages) and update the working copy.
	echo "[DEPLOY] -  * Updating application working tree"
	env -i git add .
	env -i git reset --hard || exit_with_error
	env -i git fetch -p
	env -i git checkout -f $branch
	env -i git pull origin $branch

	echo "[DEPLOY] -  * Running bundle"
	bundle install || exit_with_error

	echo "[DEPLOY] -  * Migrating database"
	bundle exec rake scopi:alter[0] || exit_with_error #This is a custom task, you can use rake db:migrate instead

	echo "[DEPLOY] -  * Restarting application"
	bundle exec pumactl -P /home/scopi/apps/scopi/tmp/pids/puma.pid restart

	echo "[DEPLOY] -  * Successfully deployed application to ${APP_PATH}"
done