WordPress Backup Script

#!/bin/bash
WPDIR="/srv/www/wp"
# Must be dumped to stdout, usually -c for bzip2, gzip, and xz
COMPRESS="bzip2 -c9"
# If DB_NAME is left blank, we'll try to fill these in from the WP config
DB_NAME=""
DB_USER=""
DB_PASSWORD=""
DATE="`date +%Y-%m-%d`"
# This function tries to get the database info from the WordPress config
# TODO write me 🙂
function get_database_info() {
	echo "To be written"
	exit 1
}
# "Returns" the extention based on the COMPRESS variable
# Keep in mind that only one echo can be in this function, and it's used with
# a call to it via: `file_ext`
function file_ext() {
	local EXT="${COMPRESS:0:2}"
	if [ "$EXT" = "bz" ]; then
		EXT="bz2"
	fi
	# our "return" value
	echo $EXT
}
# $1 is the old file/dir and $2 is the new file/dir
function compressed_stats() {
	if [ "$#" -ne 2 ]; then
		echo "Incorrect amount of arguments passed to compressed_stats"
		exit -1
	fi
	local OLDSIZE
	local NEWSIZE
	# Check if the passed argument is already a number.
	# This fails if the file passed in is only numeric.
	# This check also fails if $1 is a decimal number, lucky for us, it's a byte
	# count
	# Credit goes to jilles on StackOverflow for pointing this out.
	case $1 in
		# It's most likely a file
		''|*[!0-9]*)
			OLDSIZE="`du -b $1 | cut -f1`"
			;;
		# Otherwise, it's a number, just set the size
		*)
			OLDSIZE=$1
			;;
	esac
	case $2 in
		''|*[!0-9]*)
			NEWSIZE="`du -b $2 | cut -f1`" ;;
		*)
			NEWSIZE=$2 ;;
	esac
	# We were most likely given filenames that don't exist
	if [ "$OLDSIZE" = "" -o "$NEWSIZE" = "" ]; then
		echo "Not giving stats on files that don't exist!"
		return
	fi
	# Give some statistics about how much the database was compressed
	if [ "`which awk`" ]; then
		echo -n "compression ratio: "; echo - | awk "{ print $OLDSIZE/$NEWSIZE }"
		echo -n "Old size: "; echo - | awk "{ print $OLDSIZE/1024 }"
		echo -n "New size: "; echo - | awk "{ print $NEWSIZE/1024 }"
	elif [ "`which bc`" ]; then
		echo compression ratio: `bc $OLDSIZE/$NEWSIZE`
		echo Old size: `bc $OLDSIZE/1024`
		echo New size: `bc $NEWSIZE/1024`
	fi
}
# Dump the database
function dump_db() {
	local FILENAME="wp_backup_$DATE"
	local EXT="`file_ext`"
	if [ "$DB_NAME" = "" ]; then
		get_database_info
	fi
	echo "Dumping mysql database to $FILENAME"
	mysqldump -p"$DB_PASSWORD" -u$DB_USER $DB_NAME > $FILENAME
	echo "Compressing $FILENAME with $COMPRESS"
	$COMPRESS $FILENAME > $FILENAME.$EXT
	compressed_stats $FILENAME $FILENAME.$EXT
	rm "$FILENAME"
}
# Backup the WordPress directory
function backup_wp() {
	local EXT="`file_ext`"
	local FILENAME="wp-$DATE.tar.$EXT"
	local CURPWD="$PWD"
	echo "Backing up $WPDIR to $FILENAME"
	(cd $WPDIR/..; tar -cf - -X $CURPWD/$0.excludes "`basename $WPDIR`") | $COMPRESS > $FILENAME
	compressed_stats `(cd $WPDIR/..; tar -cf - -X $CURPWD/$0.excludes "$(basename $WPDIR)") | wc -c` $FILENAME
}
# Help dummy
function print_help() {
	echo "Usage: $0 [-d] [-b] [-h]"
	echo "	-d Dump wordpress database"
	echo "	-b Backup WordPress directory"
	echo "	-h This message"
}
# tar fails without this file, make sure it exists
[ -e $0.excludes ] || touch $0.excludes
# Parse our arguments
if [ $# -ne 0 ]; then
	while getopts ":dbh" Opt; do
		case $Opt in
			d) dump_db ;;
			b) backup_wp ;;
			h) print_help ;;
			*) echo "Unknown option"; exit ;;
		esac
	done
else
	# Default to backing up the database and directory
	dump_db
	backup_wp
fi

function f() {
	[ -e "$1" ] || return 0
	return 1
}

function f() {
	if [ -e "$1" ]; then
		echo "Exists"
	else
		echo "Failed"
	fi
}
v=`f "test.file"`
echo $v
echo `f "file.test"`