#!/bin/sh

# Goal: backup a directory
# $1: Destination
# $2: Server name (i.e.: onelab2)
# $3: Backup name (i.e.: twiki)
# $4: Date
# $5: Directory to backup
function backup_dir {
	DEST=$1
	BACKUP_NAME=$1/$2-$3-$4.tar.bz2
	DIR=$5
	mkdir -p $DEST
	if [ ! -d $DIR ]; then
		echo " (No such directory) [KO]"
		return 1
	fi
	cd $DIR
	echo -n "Backup directory $DIR..."
	tar cfjp $BACKUP_NAME *
	RES=$?
	echo -n " (`stat --printf="%s" $BACKUP_NAME`)"
	if [ $RES -eq 0 ]; then
		echo " [ OK ]"
	else
		echo " [ KO ]"
	fi

	return 0
}

# Goal: backup a PostgreSQL database
# $1: Destination
# $2: Server name (i.e.: onelab2)
# $3: Date
# $4: Database name
# $5: Database owner
function backup_db {
	DEST=$1
	DBNAME=$4
	DBUSER=$5
	BACKUP_NAME=$DEST/$2-db-$DBNAME-$3.bak
	mkdir -p $DEST
	echo -n "Backup database $DBNAME..."
	pg_dump -i -U postgres --user=$DBUSER -F c -f $BACKUP_NAME $DBNAME
	RES=$?
	echo -n " (`stat --printf="%s" $BACKUP_NAME`)"
	if [ $RES -eq 0 ]; then
		echo " [ OK ]"
	else
		echo " [ KO ]"
		return 1
	fi

	return 0
}

# Goal: backup all PostgreSQL databases on the machine
# $1: Destination
# $2: Server name (i.e.: onelab2)
# $3: Date
function backup_all_dbs {
	for i in `psql -qtAF '|' -U postgres -l`; do
		DBNAME=`echo $i | cut -d '|' -f 1`
		DBUSER=`echo $i | cut -d '|' -f 2`
		if [ $DBNAME != template0 -a $DBNAME != template1 ]; then
			backup_db $1 $2 $3 $DBNAME $DBUSER
		fi
	done
}

# Goal: backup a database in a VServer
# $1: Destination
# $2: VServer name (i.e.: onelab2)
# $3: Backup name (i.e.: twiki)
# $4: Date
# $5: Database name
# $6: Database owner
function backup_vserver_db {
	DEST=$1
	VSERVER=$2
	BACKUP_NAME=$1/$2-$3-$4.bak
	DBNAME=$5
	DBUSER=$6
	mkdir -p $DEST
	mkdir -p /vservers/$VSERVER/$DEST
	echo -n "Backup database $DBNAME..."
	vserver $VSERVER exec \
		pg_dump -i -U postgres --user=$DBUSER -F c -v -f $BACKUP_NAME \
		-- $DBNAME >/dev/null
	RES=$?
	mv /vservers/$VSERVER/$BACKUP_NAME $BACKUP_NAME
	echo -n " (`stat --printf="%s" $BACKUP_NAME`)"
	if [ $RES -eq 0 ]; then
		echo " [ OK ]"
	else
		echo " [ KO ]"
		return 1
	fi

	return 0
}

# Goal: backup an offline vserver instance
# $1: Destination (where to save the backup)
# $2: VServer name (i.e.: plc)
# $3: Date
function backup_vserver_offline {
	DEST=$1
	VSERVER=$2
	BACKUP_NAME=$1/$2-vs-$3.off.tar.bz2
	BACKUP_CONF_NAME=$1/$2-vsconf-$3.off.tar.bz2
	mkdir -p $DEST
	echo -n "Backup vserver $VSERVER..."
	if [ ! -d /etc/vservers/$VSERVER ]; then
		echo " (No such vserver) [ KO ]"
		return 1
	fi

	cd /etc/vservers/$VSERVER &&
	tar cfjp $BACKUP_CONF_NAME * 2>&1 >/dev/null &&
	cd /vserver/$VSERVER &&
	tar cfjp $BACKUP_NAME * 2>&1 >/dev/null
	RES=$?

	echo -n " (`stat --printf="%s" $BACKUP_NAME`)"
	if [ $RES -eq 0 ]; then
		echo " [ OK ]"
	else
		echo " [ KO ]"
		return 1
	fi

	return 0
}

# Goal: backup an online vserver instance
# $1: Destination (where to save the backup)
# $2: VServer name (i.e.: plc)
# $3: Date
# $4: LVM dev on which the VServer is mounted (default to /dev/vg/$2 if empty)
function backup_vserver_online {
	DEST=$1
	VSERVER=$2
	BACKUP_NAME=$1/$2-vs-$3.on.tar.bz2
	BACKUP_CONF_NAME=$1/$2-vsconf-$3.on.tar.bz2
	DEV=$4
	if [ -z $DEV ]; then
		DEV="/dev/vg/$VSERVER"
	fi

	echo -n "Backup vserver $VSERVER..."
	mkdir -p $DEST >/dev/null
	
        SNAPDEV=${DEV}bkp
        if [ ! -d /etc/vservers/$VSERVER ]; then
		echo " (No such vserver) [ KO ]"
                return 1
        fi

	# Create a snapshot of the running vserver filesystem...
        SNAPVG=`echo $SNAPDEV | cut -f 3 -d '/'`
        SNAPLV=`echo $SNAPDEV | cut -f 4 -d '/'`
        SNAPMOUNT=/tmp/$SNAPLV
        lvcreate -L20G -s -n$SNAPLV $DEV >/dev/null
	if [ $? -ne 0 ]; then
		echo " (Can't create snapshot volume: $SNAPDEV) [ KO ]"
		return 1
	fi

        # ... mount it and backup it...
	cd /etc/vservers/$VSERVER &&
	tar cfjp $BACKUP_CONF_NAME * &&
        mkdir -p $SNAPMOUNT &&
        mount -t ext3 $SNAPDEV $SNAPMOUNT -o ro &&
        cd $SNAPMOUNT &&
        tar cfjp $BACKUP_NAME * 2>/dev/null >/dev/null
	RES=$?

	# ... and remove the snapshot
	cd &&
        umount $SNAPMOUNT &&
        lvremove -f $SNAPDEV >/dev/null &&
        rmdir $SNAPMOUNT
	if [ $? -ne 0 ]; then
		echo " (Can't delete snapshot volume: $SNAPDEV) [ KO ]"
		return 1
	fi

	echo -n " (`stat --printf="%s" $BACKUP_NAME`)"
	if [ $RES -eq 0 ]; then
		echo " [ OK ]"
	else
		echo " [ KO ]"
		return 1
	fi

	return 0
}

# Goal: backup a vserver instance (online or offline)
# $1: Destination (where to save the backup)
# $2: VServer name (i.e.: onelab2)
# $3: Date
function backup_vserver {
	DEST=$1
	VSERVER=$2
	DATE=$3
	if [ ! -d /etc/vservers/$VSERVER ]; then
		echo "Backup vserver $VSERVER... (No such vserver) [ KO ]"
	fi

	ctx=`cat /etc/vservers/$VSERVER/context`
	vserver-stat | grep $ctx 2>&1 > /dev/null
        offline=$?

        if [ $offline -eq 0 ]; then
                backup_vserver_online $DEST $VSERVER $DATE
        else
                backup_vserver_offline $DEST $VSERVER $DATE
        fi
        return $?
}

# Goal: backup all vserver instances (online or offline) on the machine
# $1: Destination (where to save the backup)
# $2: Date
function backup_all_vservers {
	for i in /etc/vservers/*; do
		VSERVER=`basename $i`
		backup_vserver $1 $VSERVER $2
	done
}

# Fetch all backups from a server
# $1: destination
# $2: hostname
# $3: backup user
# $4: backup location
function fetch_backup {
	DEST=$1
	BACKUP_HOST=$2
	BACKUP_USER=$3
	BACKUP_LOC=$4
	echo -n "Fetch backups from $BACKUP_HOST..."
	su $BACKUP_USER -c "mkdir -pv $DEST"
	su $BACKUP_USER -c "rsync --exclude="lost+found" -a $BACKUP_USER@$BACKUP_HOST:$BACKUP_LOC/ $DEST"
	RES=$?
	if [ $RES -eq 0 ]; then
		echo " [OK]"
	else
		echo " [KO]"
	fi
	
	return 0
}