#!/bin/bash

#
# For create user `GRANT LOCK TABLES, SELECT ON DATABASE.* TO 'BACKUPUSER'@'%' IDENTIFIED BY 'PASSWORD';`
#

#### MySQL CREDENTIAL ###

HOST='localhost'
USER='root'
PASSWD=''
DBS='db01 db02 db03'  # Databases separated by spaces
BACKUPDIRECTORY='/tmp/'  # Ex: /tmp/
EMAIL='pepito@mail.com'

#### MySQL CREDENTIAL ###

basesize=800 # Base size compare 785 normal to mysqldump
d=$(date +%Y-%m-%d_%H%M%S)

echo $(date +%Y-%m-%d' '%H:%M:%S)' Starting backup on '$HOST
echo $(date +%Y-%m-%d' '%H:%M:%S)' Starting backup on '$HOST >> backup_$d.log

echo $(date +%Y-%m-%d' '%H:%M:%S)' Saving on '$BACKUPDIRECTORY
echo $(date +%Y-%m-%d' '%H:%M:%S)' Saving on '$BACKUPDIRECTORY >> backup_$d.log

# create dump file by database with date
for DB in $DBS
do
    filename=$DB'_'$d'.sql.gz'
    path=$BACKUPDIRECTORY$filename

    echo $(date +%Y-%m-%d' '%H:%M:%S)" Init "$filename
    echo $(date +%Y-%m-%d' '%H:%M:%S)" Init "$filename >> backup_$d.log
    (mysqldump -h $HOST -u $USER --password=$PASSWD $DB | gzip > $path) 2> error_$d.log

    size=$(cat $path | wc -c)

    # check file dump is valid
    if [ $size -lt $basesize ]; then
        echo $(date +%Y-%m-%d' '%H:%M:%S)" * "$filename" failed *"
        echo $(date +%Y-%m-%d' '%H:%M:%S)" * "$filename" failed *" >> backup_$d.log
        rm -f $path
    else
        echo $(date +%Y-%m-%d' '%H:%M:%S)" - "$filename" ready"
        echo $(date +%Y-%m-%d' '%H:%M:%S)" - "$filename" ready" >> backup_$d.log
    fi
done

echo  $(date +%Y-%m-%d' '%H:%M:%S)' Finish backup'
echo  $(date +%Y-%m-%d' '%H:%M:%S)' Finish backup' >> backup_$d.log