borg-remote-android/backup-android.sh

#!/data/data/com.termux/files/usr/bin/bash
# Initialize
ABSPATH="$(readlink -f "$BASH_SOURCE")"
set -x
cd "${ABSPATH%/*}" || { echo "Cannot change directory" >&2; exit 1; }
test -f ./env && source ./env || { echo "Unable to source user variables in $PWD"; exit 1;  }

# From https://serverfault.com/a/799198
# Since Termux has no uuidgen command, we need to create one randomly
function uuidgen() {
  od -x /dev/urandom | head -1 | awk '{OFS="-"; print $2$3,$4,$5,$6,$7$8$9}'
}

# From https://unix.stackexchange.com/a/27014
function time_diff {
  # Find the time difference between the two arguments (in seconds)
  local T="$(( "$1" - "$2" ))"
  local D=$((T/60/60/24))
  local H=$((T/60/60%24))
  local M=$((T/60%60))
  local S=$((T%60))
  (( $D > 0 )) && printf '%dd ' $D
  (( $H > 0 )) && printf '%dh ' $H
  (( $M > 0 )) && printf '%dm ' $M
  (( $D > 0 || $H > 0 || $M > 0 )) && printf 'and '
  printf '%ds\n' $S
}

function backup() {
  # First, we need to rsync our changes to the host
  echo "Running rsync..."
  local RETRIES=10
  while (( RETRIES > 0 )); do
    # Try to rsync
    $RSYNC_COMMAND "$SOURCE_LOCATION" "$REMOTE_HOST:$DESTINATION_LOCATION" && break
    (( RETRIES-- ))
    echo "rsync failed. Retrying $RETRIES more times. Sleeping 10s"
    sleep 10s
  done

  if (( RETRIES == 0 )); then
    # We exceeded the retry limit. Fail
    return 1
  fi

  # Next, instruct the host to create a borg
  echo "Running borg..."
  ./run_remote.sh cd "$DESTINATION_LOCATION" "&&" pwd "&&" $BORG_COMMAND "$BORG_REPO::$HOSTNAME-$(uuidgen)" . || return 2
}

# Take wakelock so we don't fall asleep
termux-wake-lock
START_TIME="$(date +%s)"

# Perform the backup
backup
RESULT=$?
DURATION="$(time_diff "$(date +%s)" "$START_TIME" )"

echo "Completed $(date +%F-%T)"
echo "Duration: $DURATION"

if (( RESULT == 0 )); then
  termux-notification --title "Backup completed successfully in $DURATION"
else
  termux-notification --title "Backup failed in $DURATION"
fi

# Remove our wakelock
termux-wake-unlock