Variables (locally defined) not defined when running bash script from cron on MacOS

Question

I have following script for backups creation:

#!/usr/bin/env bash
{
  declare -a directories=(
    "/Applications/Apache"
    "/Applications/Scripts"
  )

  function duplicateBackups()
  {
    from=`realpath $1`
    to=`realpath $2`
    echo [ `date +"%T"` ] Copying backups from $from to $to
    cp -r $1 $2/
    sleep 1
  }

  date=`date +"%Y-%m-%d"`

  destination1='/opt/Volumes/USB1'
  destination2='/opt/Volumes/USB2'
  destination3='/opt/Volumes/FireWire'
  destination4='/opt/Volumes/USB3'
  destinationFolder='MacMini-Backups'
  targetFolder=$destination1/$destinationFolder/$date

  mkdir $targetFolder
  targetPath=`realpath $targetFolder`

  echo [ `date +"%T"` ] Starting files backups

  for i in "${directories[@]}"
  do
    fileName="$(basename $i)"
    mkdir -p $targetFolder/Files/
    echo [ `date +"%T"` ] Backing up "$i" as "$targetPath/Files/$fileName.tgz"
    tar -Pczf $targetFolder/Files/$fileName.tgz -C $i .
    sleep 1
  done
  echo [ `date +"%T"` ] Files backups finished
  sleep 1
  echo [ `date +"%T"` ] Starting databases backup
  sleep 1

  mkdir -p $targetFolder/Databases/

  echo [ `date +"%T"` ] Backing up all databases into $targetPath/Databases/full-dump.sql.gz
  mysqldump --opt --all-databases --skip-lock-tables | gzip -c > $targetFolder/Databases/full-dump.sql.gz

  for db in `mysql -se "show databases;"`;
  do
    if [[ ${db} != *"schema"* ]]; then
      echo [ `date +"%T"` ] Backing up database $db into $targetPath/Databases/$db-dump.sql.gz
      mysqldump --skip-lock-tables --opt $db | gzip -c > $targetFolder/Databases/$db-dump.sql.gz
      sleep 1
    fi
  done;
  echo [ `date +"%T"` ] Databases backup finished
  sleep 1

  duplicateBackups $destination1/$destinationFolder/$date $destination2/$destinationFolder
  duplicateBackups $destination1/$destinationFolder/$date $destination3/$destinationFolder
  duplicateBackups $destination1/$destinationFolder/$date $destination4/$destinationFolder

} >> /Applications/Scripts/Logs/backups.log

This script works absolutely fine when I am running it manually, no matter if this is from shell, bash or ZSH.

This is how the log file looks like in that case:

[ 09:26:05 ] Starting files backups
[ 09:26:05 ] Backing up /Applications/Apache as /Volumes/USB1/MacMini-Backups/2020-12-31/Files/Apache.tgz
[ 09:27:14 ] Backing up /Applications/Scripts as /Volumes/USB1/MacMini-Backups/2020-12-31/Files/Scripts.tgz
[ 09:27:15 ] Files backups finished
[ 09:27:16 ] Starting databases backup
[ 09:27:17 ] Backing up all databases into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/full-dump.sql.gz
[ 09:27:35 ] Backing up database Cloud into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/Cloud-dump.sql.gz
[ 09:27:36 ] Backing up database mysql into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/mysql-dump.sql.gz
[ 09:27:38 ] Backing up database radek into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/site-dump.sql.gz
[ 09:27:41 ] Backing up database radek_j3 into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/site_j3-dump.sql.gz
[ 09:27:45 ] Backing up database test into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/test-dump.sql.gz
[ 09:27:46 ] Backing up database site_j3 into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/joomla_3-dump.sql.gz
[ 09:27:48 ] Backing up database joomla_dev into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/joomla_dev-dump.sql.gz
[ 09:27:49 ] Backing up database joomla_dev2 into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/joomla_dev2-dump.sql.gz
[ 09:27:51 ] Backing up database joomla_j4 into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/joomla_j4-dump.sql.gz
[ 09:27:53 ] Backing up database joomla_site into /Volumes/USB1/MacMini-Backups/2020-12-31/Databases/joomla_site-dump.sql.gz
[ 09:28:06 ] Databases backup finished
[ 09:28:07 ] Copying backups from /Volumes/USB1/MacMini-Backups/2020-12-31 to /Volumes/USB2/MacMini-Backups
[ 09:28:30 ] Copying backups from /Volumes/USB1/MacMini-Backups/2020-12-31 to /Volumes/FireWire/MacMini-Backups
[ 09:28:43 ] Copying backups from /Volumes/USB1/MacMini-Backups/2020-12-31 to /Volumes/USB3/MacMini-Backups

However if I would run it through cronjob, Automator or even Apple Calendar the log file looks like that:

[ 06:00:00 ] Starting files backups
[ 06:00:00 ] Backing up /Applications/Apache as /Files/Apache.tgz
[ 06:01:22 ] Backing up /Applications/Scripts as /Files/Scripts.tgz
[ 06:01:23 ] Files backups finished
[ 06:01:25 ] Starting databases backup
[ 06:01:26 ] Backing up all databases into /Databases/full-dump.sql.gz
[ 06:01:26 ] Databases backup finished
[ 06:01:27 ] Copying backups from to
[ 06:01:46 ] Copying backups from to
[ 06:01:58 ] Copying backups from to

I assume that these variables I defined in that script do not have any effect.

Does anyone know what the issue here may be?

Answer 1

Thanks a lot to bitinerant and Mark Wagner for their help. After I added the error output it turned out it was a mix between missing paths and lack of permissions to access directories and read list of databases from MySQL.

Thanks a lot