#!/bin/bash
# Database Dump utility for MySQL. Put in cron like this:
#
#  DUMPDIR='/home/example/DatabaseDumps' USER='dbuser' PASS='dbpass' DB='dbname' /path/to/dumpdb.sh
#
# (C) 2009 vjt@openssl.it
#

[ -z "$MAXAGE" ] && MAXAGE=744

[ -z "$DUMPDIR" -o -z "$USER" -o -z "$PASS" -o -z "$DB" ] && {
  echo "Please pass correct environment: DUMPDIR ($DUMPDIR), USER ($USER), PASS ($PASS) and DB ($DB) [MAXAGE ($MAXAGE)]"
  exit 1
}

set -e

current_md5() {
  md5sum $DUMPDIR/`ls -t1 $DUMPDIR | head -1` 2>/dev/null | awk '{print $1}'
}

# Dump
previous_md5=`current_md5`
dump="$DUMPDIR/`whoami`-`date +%Y%m%d`.sql.bz2"

[ -f "$dump" ] && exit 0

mysqldump -ec -u $USER -p$PASS $DB | grep -v '^-- Dump' | bzip2 -9 > $dump
chmod 640 $dump
#chgrp dropbox $dump

# Cleanup
[ "$previous_md5" = "`current_md5`" ] && rm -f $dump
find $DUMPDIR -mtime $MAXAGE -exec rm -f {} \;