setup

docker-compose up -d

config file

maxscale.cnf.d
├── example.cnf
└── masking_rules.json

access mysql

docker-compose exec mysql mysql -umaxuser -pmaxpwd -h localhost test

access mysql via maxscale

docker-compose exec mysql mysql -umaxuser -pmaxpwd -h maxscale test -P 4008

masking check

% docker-compose exec mysql mysql -umaxuser -pmaxpwd -h localhost test -e "select * from masking1;"
Warning: Using a password on the command line interface can be insecure.
+---------------------+
| card_number1        |
+---------------------+
| 1234-5678-9012-3456 |
| 1234-5678-9013-3456 |
| 1234-5678-9014-3456 |
+---------------------+

% docker-compose exec mysql mysql -umaxuser -pmaxpwd -h maxscale test -P 4008 -e "select * from masking1;"
Warning: Using a password on the command line interface can be insecure.
+---------------------+
| card_number1        |
+---------------------+
| ******************* |
| ******************* |
| ******************* |
+---------------------+