#!/usr/bin/env bash
#
# The backup script for GretaThemes VPS
# - Automatic backup all databases in format $database-$Y-$m-$d.sql.gz
# - Send backups to Dropbox
# - Send customers.csv from Theme Updater to Dropbox
#
# Written by: Tran Ngoc Tuan Anh <rilwis@gmail.com>
# Last update: October 1st, 2016

# Exit when a command fails
set -o errexit

# Fail fast and be aware of exit codes
set -eo pipefail

# The main function
main() {
	local folder=/path/to/backup/folder/
	local today=$(date +%F)
	local user="YOUR MYSQL USERNAME"
	local password="YOUR MYSQL PASSWORD"
	local dump="mysqldump --skip-extended-insert --force"
	local file
	local database

	echo "Start backup databases";

	# Get list of all databases
	local databases=$(echo "SHOW databases" | mysql -u $user -p"$password")

	for database in $databases; do

		# Skip if this is the default built-in MySQL database
		if [ "$database" = "Database" ] || [ "$database" = "information_schema" ] || [ "$database" = "mysql" ] || [ "$database" = "performance_schema" ] || [ "$database" = "sys" ]
		then
			continue
		fi

		# Backup
		echo "Backup the database $database";
		file="$folder/$database-$today.sql.gz"
		$dump -u $user -p"$password" $database | gzip -9 > $file

		# Upload to Dropbox
		echo "Upload the database $database to Dropbox";
		upload $file $today/$database-$today.sql.gz

	done

	echo "Cleaning up the backup folder"
	cleanup $folder

	echo "Notify admin that the back up is completed"
	notify $today youremail@domain.com
}

# Upload a file to Dropbox
#
# @param $1 File to upload
# @param $2 File to store on Dropbox
upload() {
	/path/to/dropbox_uploader.sh upload $1 $2
}

# Cleanup the backup folder, remove backups older than 30 days
cleanup() {
	find "$1"/* -mtime +30 -exec rm {} \;
}

# Notify admin that the back up is completed
#
# @param $1 Date
# @param $2 Email address
notify() {
	echo "Backup for server on $1 is completed." | mail $2 -s "Daily server backup on $1"
}

# Call the main function
main