Bash Script to backup all MySQL databases

mysql_backup.sh

#!/bin/bash
#==============================================================================
#TITLE:            mysql_backup.sh
#DESCRIPTION:      script for automating the daily mysql backups on development computer
#AUTHOR:           tleish
#DATE:             2013-12-20
#VERSION:          0.4
#USAGE:            ./mysql_backup.sh
#CRON:
  # example cron for daily db backup @ 9:15 am
  # min  hr mday month wday command
  # 15   9  *    *     *    /Users/[your user name]/scripts/mysql_backup.sh

#RESTORE FROM BACKUP
  #$ gunzip < [backupfile.sql.gz] | mysql -u [uname] -p[pass] [dbname]

#==============================================================================
# CUSTOM SETTINGS
#==============================================================================

# directory to put the backup files
BACKUP_DIR=/Users/[your user name]/backup

# MYSQL Parameters
MYSQL_UNAME=root
MYSQL_PWORD=

# Don't backup databases with these names 
# Example: starts with mysql (^mysql) or ends with _schema (_schema$)
IGNORE_DB="(^mysql|_schema$)"

# include mysql and mysqldump binaries for cron bash user
PATH=$PATH:/usr/local/mysql/bin

# Number of days to keep backups
KEEP_BACKUPS_FOR=30 #days

#==============================================================================
# METHODS
#==============================================================================

# YYYY-MM-DD
TIMESTAMP=$(date +%F)

function delete_old_backups()
{
  echo "Deleting $BACKUP_DIR/*.sql.gz older than $KEEP_BACKUPS_FOR days"
  find $BACKUP_DIR -type f -name "*.sql.gz" -mtime +$KEEP_BACKUPS_FOR -exec rm {} \;
}

function mysql_login() {
  local mysql_login="-u $MYSQL_UNAME" 
  if [ -n "$MYSQL_PWORD" ]; then
    local mysql_login+=" -p$MYSQL_PWORD" 
  fi
  echo $mysql_login
}

function database_list() {
  local show_databases_sql="SHOW DATABASES WHERE \`Database\` NOT REGEXP '$IGNORE_DB'"
  echo $(mysql $(mysql_login) -e "$show_databases_sql"|awk -F " " '{if (NR!=1) print $1}')
}

function echo_status(){
  printf '\r'; 
  printf ' %0.s' {0..100} 
  printf '\r'; 
  printf "$1"'\r'
}

function backup_database(){
    backup_file="$BACKUP_DIR/$TIMESTAMP.$database.sql.gz" 
    output+="$database => $backup_file\n"
    echo_status "...backing up $count of $total databases: $database"
    $(mysqldump $(mysql_login) $database | gzip -9 > $backup_file)
}

function backup_databases(){
  local databases=$(database_list)
  local total=$(echo $databases | wc -w | xargs)
  local output=""
  local count=1
  for database in $databases; do
    backup_database
    local count=$((count+1))
  done
  echo -ne $output | column -t
}

function hr(){
  printf '=%.0s' {1..100}
  printf "\n"
}

#==============================================================================
# RUN SCRIPT
#==============================================================================
delete_old_backups
hr
backup_databases
hr
printf "All backed up!\n\n"

How would I modify this so I could specify the host and port?

@uSlackr Try adding -h YOURHOSTNAME -P YOURPORT on line 75.
Something like: $(mysqldump $(mysql_login) -h YOURHOSTNAME -P YOURPORT $database | gzip -9 > $backup_file)

Thanks. I'd figured this out but forgot to post back.

Is possible to modify this script to only backup databases that have data, to avoid have files with 0kb from databases with no data?