lxd-backup

#!/bin/bash
set -e

command -v incus >/dev/null 2>&1 && BINARY=incus ||
	{
		command -v lxd >/dev/null 2>&1 && BINARY=lxc ||
			{
				echo "did not find neither incus nor lxd binary in path." >&2;
				exit 1;
			}
	}

function log {
	echo "$(date '+%Y-%m-%d %H:%M:%S') | $1"
}

function do_import {
	ARGNUM=2
	if [ $# -lt $(($ARGNUM-1)) ] || [ $# -gt $ARGNUM ]; then
	  echo 1>&2 "$0 import {imagePath} {containerName}"
	  exit 2
	fi

	IMPORTPATH=$1
	IMPORTFILE=$(basename -- "$IMPORTPATH")
	DEFAULTCONTAINER=${IMPORTFILE%%.*}
	CONTAINER=${2:-$DEFAULTCONTAINER}
	HASH=$(echo $CONTAINER | shasum | cut -b 1-40)
	IMAGE="$HASH-import"

	log "importing template $IMPORTPATH as container $CONTAINER"

	log "importing image file"
	$BINARY image delete $IMAGE 2>/dev/null || true
	$BINARY image import $IMPORTPATH --alias=$IMAGE >/dev/null

	log "creating container"
	$BINARY init $IMAGE $CONTAINER >/dev/null || true

	log "cleaning up"
	$BINARY image delete $IMAGE 2> /dev/null

	log "done."

}

function do_export {
	ARGNUM=2
	if [ $# -lt $ARGNUM ] || [ $# -gt $ARGNUM ]; then
	  echo 1>&2 "$0 export {containerName} {exportPath without .tar.gz}"
	  exit 2
	fi

	if $BINARY info $1 2>/dev/null | egrep -iqc "status: running"; then
	  ISRUNNING=true
	else
	  ISRUNNING=false
	fi

	CONTAINER=$1
	EXPORTPATH=${2%/}
	if [[ -d $EXPORTPATH ]]; then
		EXPORTPATH+="/$CONTAINER"
	fi
	HASH=$(echo $CONTAINER | shasum | cut -b 1-40)
	IMAGE="$HASH-export"
	SNAPSHOT="$HASH-export"

	touch $EXPORTPATH.tmp
	rm $EXPORTPATH.tmp

	log "exporting container $CONTAINER to $EXPORTPATH.tar.gz"

	log "preparing snapshot"
	$BINARY delete $CONTAINER/$SNAPSHOT 2>/dev/null || true
	$BINARY image delete $IMAGE 2>/dev/null || true

	if [ "$ISRUNNING" = true ] ; then
	  log "stopping container"
	  $BINARY stop $CONTAINER 2>/dev/null
	fi

	log "creating snapshot"
	$BINARY snapshot $CONTAINER $SNAPSHOT >/dev/null

	if [ "$ISRUNNING" = true ] ; then
	  log "starting container"
	  $BINARY start $CONTAINER
	fi

	log "creating image"
	$BINARY publish $CONTAINER/$SNAPSHOT --alias=$IMAGE description="Exported from $CONTAINER at $(date '+%Y-%m-%d %H:%M')" >/dev/null

	log "exporting image"
	$BINARY image export $IMAGE $EXPORTPATH >/dev/null

	log "cleaning up"
	$BINARY delete $CONTAINER/$SNAPSHOT
	$BINARY image delete $IMAGE

	log "done."
}

function do_clean {
	ARGNUM=1
	if [ $# -lt $ARGNUM ] || [ $# -gt $ARGNUM ]; then
	  echo 1>&2 "$0 clean {containerName}"
	  exit 2
	fi

	CONTAINER=$1
	EXPORTPATH=$2
	HASH=$(echo $CONTAINER | shasum | cut -b 1-40)
	IMAGE="$HASH-export"

	log "Cleaning backup data for container $CONTAINER"

	log "Removing container snapshot.."
	$BINARY delete $CONTAINER/$IMAGE 2>/dev/null || true
	log "Removing image.."
	$BINARY image delete $IMAGE 2>/dev/null || true
	log "done."
}

case $1 in
        "clean")
                do_clean $2
                ;;
        "export")
                do_export $2 $3
                ;;
        "import")
                do_import $2 $3
                ;;
        *)
                echo "Wrong Parameters! Usage: [ export | import | clean | help ]"
                ;;
esac