Convenience script for rsync - to check for availability of a locally mounted network share and mirror files one way using rsync.

mync.sh

#!/bin/bash
#
# Copyright (c) 2018 Stephan Rickauer <stephan@rickauer.com>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

# Convenience script for rsync - to check for availability of a locally
# mounted network share and mirror files one way using rsync. Supposed to
# run on Mac OS X only, tested on Mojave. Requires rsync >= 3.


# Home directory of the user.
stem='/Users/username'

# Sub directories to mirror (replace with $stem/* for all).
sources=(
	$stem/Documents
	$stem/Desktop
	$stem/Downloads
	$stem/Applications
	$stem/Software
	$stem/Movies
	$stem/Public
	$stem/Pictures
	$stem/Music
	$stem/Applications
	$stem/.ssh
) 

# Local mount point of network share (destination share).
share='/Volumes/Your-Share'

# Remote destination sub folder to mirror into. Set to "$share" for 'none'.
dest="$share/rsync"

# On Mac, typically not required to change anything beyond here
df='/bin/df'
awk='/usr/bin/awk'
rsync='/usr/local/bin/rsync'
mount='/sbin/mount'
bins=($df $awk $rsync $mount)

# Functions go first
function check_binaries() {
	for bin in ${bins[*]}; do
		[[ -x $bin ]] || { echo "$bin does not execute!"; exit 1; }
	done
}

function check_rsync_version() {
	# rsync versions < 3 lack support for UTF8 conversion (--iconv).
	# see https://www.kigmbh.com/2011/04/rsync_delete_umlaut_problem/
	rsync_version=`$rsync --version | $awk -F'[ .]' '/version/{print $4}'`
	if [ "$rsync_version" -lt '3' ]; then
                echo "This $rsync version lacks iconv support for UTF8! Consider updating."
                exit 1
        fi
}

function check_sources() {
	for source in ${sources[*]}; do
		[[ -d $source ]] || { echo "$source not found!"; exit 1; }
	done
}

function check_destination() {
	# Check if given share is listed under mounted file systems.
	$mount | grep $share >/dev/null
	if [ $? == '1' ]; then
		echo "$share does not seem to be mounted, mount share manually!"
		exit 1
	fi

	# Verify if mount point directory was created during mount of network share.
	[[ -d $dest ]] || { echo "Directory $dest missing, try to mount share!"; exit 1; }

	# Require at least 100 MB free disk space on remote share.
	available_space=`$df -k "$share" | $awk '/[0-9]%/{print $(NF-5)}'`
	if [ "$available_space" -lt '100000' ]; then
		echo "$available_space is not enough!"
		exit 1
	fi
}

function mirror_files() {
	$rsync -avz --iconv=UTF8,UTF8-MAC --delete --exclude {.cache,.Trash} ${sources[*]} $dest/
}

# Main
check_binaries
check_rsync_version
check_sources
check_destination
mirror_files