MySQL Master Slave configuration using Docker-compose - mysql

Question

Okay so I wanted to make a master slave replication for mysql for my website hosted in nginx run by php. I've managed to connect to the master mysql however, there seems to have some error on my slave container. I was wondering if there is anything wrong or what I should add in order to solve this issue.
You need to specify one of MYSQL_ROOT_PASSWORD, MYSQL_ALLOW_EMPTY_PASSWORD and MYSQL_RANDOM_ROOT_PASSWORD
2020-10-15 09:09:44+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 1:10.5.6+maria~focal started.
2020-10-15 09:09:45+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
2020-10-15 09:09:45+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 1:10.5.6+maria~focal started.
2020-10-15 09:09:45+00:00 [ERROR] [Entrypoint]: Database is uninitialized and password option is not specified
You need to specify one of MYSQL_ROOT_PASSWORD, MYSQL_ALLOW_EMPTY_PASSWORD and MYSQL_RANDOM_ROOT_PASSWORD
My docker-compose.yml file
version: "3.3"
services:
mysql:
image: mariadb:latest
restart: always
ports:
- "3306"
environment:
MYSQL_REPLICATION_MODE: master
MYSQL_REPLICATION_USER: repl_user
MYSQL_REPLICATION_PASSWORD: repl_password
MYSQL_ROOT_PASSWORD: rootpw
MYSQL_DATABASE: database
MYSQL_USER: user
MYSQL_PASSWORD: mypw
networks:
- my-net
mysql-slave:
image: mariadb:latest
restart: always
ports:
- "3306"
depends_on:
- mysql
environment:
MYSQL_REPLICATION_MODE: slave
MYSQL_REPLICATION_USER: repl_user
MYSQL_REPLICATION_PASSWORD: repl_password
MYSQL_MASTER_HOST: mysql
MYSQL_MASTER_PORT_NUMBER: 3306
MYSQL_MASTER_ROOT_PASSWORD: rootpw
MYSQL_ROOT_PASSWORD: rootpw
networks:
- my-net
myphp:
build: ./src/php
restart: always
expose:
- "9000"
volumes:
- ./src:/var/www/html
depends_on:
- mysql
- mysql-slave
networks:
- my-net
mynginx:
image: nginx
restart: always
volumes:
- ./src/nginx.ini:/etc/nginx/conf.d/default.conf
- ./src/php-fpm.conf:/etc/php/7.4/fpm/php-fpm.conf
- ./src/www.conf:/etc/php/7.4/fpm/pool.d/www.conf
- ./src:/var/www/html/
ports:
- "8080:80"
depends_on:
- myphp
networks:
- my-net
networks:
my-net:
driver: bridge