Backup files to Google Drive

backup.sh

#!/bin/sh

# Author: Jacob Riddle
# Email: useafterfree.consulting@gmail.com
#
# This script will backup a file to Google Drive. Each time this script is
# called it will create a compressed archive of the path, given as an argument,
# in /tmp. Each archive will have an accompanying checksum file for integrety
# verification. It will name the archive according to the following scheme:
#
# For daily backups:
# $basename-backup-(Mon|Tues|Wed|Thru).tar.gz
#
# For weekly backups:
# $basename-backup-w(0-7).tar.gz
#
# Backups will occur nightly with files being over-written as needed. Daily
# backups are on a five(5) day rotation. Weekly ones are on a eight(8) week
# rotation. Each archive will have an accompanying checksum file for integrety
# verification.
#
# Example usage:
#
# $> backup.sh /var/www/wiki
#
# This script requires rclone (rclone.org) to be installed.

# set -x # Debug
path=$1

# Day of week
day=$(date +"%a")
filename="$(basename $path)-backup"
backup_location="$(mktemp -d)"
tar_cmd="tar --selinux -czf" # To extract run 'tar --selinux -xvf'

# Number of weeks between rotations
rotate_week=8

# Create daily archive
create_arc () {
    local file=$1
    local time=$2

    cd $backup_location
    $tar_cmd $file-$time.tar.gz $path
    sha256sum $file-$time.tar.gz > $file-$time.sha256
}

# Creates weekly archive.
create_week_arc () {
    # Current week
    # local week=$(date +%U)
    let "week= $(date +%U) % $rotate_week"
    local file=$1
    local dow=$2

    if test $dow = "Fri"; then
        cd $backup_location
        mv $file-$dow.tar.gz $file-$week.tar.gz && mv $file-$dow.sha256 $file-$week.sha256
    fi
}

# Copy files to Google Drive
copy() {
    local dir=$1
    cd $dir
    for i in *; do
        rclone copy $i backup:/
    done
}

create_arc $filename $day
create_week_arc $filename $day
copy $backup_location

# Clean up
rm -r $backup_location