Error while Dockerizing a CRUD RESTful API with Go, MySQL - mysql

Question

I'm getting issue while running docker compose up , You can see my docker-compose.yaml file that I wrote for running the web API with MySQL db. I've also attached the error I'm facing currently. It'll be a great help if you can help me in this regard. thanks.
version: '3'
services:
app:
container_name: web_api
build: .
ports:
- 8080:5000
restart: on-failure
volumes:
- api:/usr/src/app/
depends_on:
- webapi-mysql
networks:
- webapi
webapi-mysql:
image: mysql:8.0.26
container_name: db_mysql
ports:
- 3308:3306
environment:
- MYSQL_ROOT_HOST=${DB_HOST}
- MYSQL_USER=${DB_USER}
- MYSQL_PASSWORD=${DB_PASSWORD}
- MYSQL_DATABASE=${DB_NAME}
- MYSQL_ROOT_PASSWORD=${DB_PASSWORD}
volumes:
- database_mysql:/var/lib/mysql
networks:
- webapi
volumes:
api:
database_mysql:
# Networks to be created to facilitate communication between containers
networks:
webapi:
driver: bridge
Error is coming up in my CLI, as follows
Attaching to db_mysql, web_api
db_mysql | 2021-11-08 13:20:28+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.26-1debian10 started.
db_mysql | 2021-11-08 13:20:28+00:00 [Note] [Entrypoint]: Switching to dedicated user 'mysql'
db_mysql | 2021-11-08 13:20:28+00:00 [Note] [Entrypoint]: Entrypoint script for MySQL Server 8.0.26-1debian10 started.
db_mysql | 2021-11-08 13:20:28+00:00 [ERROR] [Entrypoint]: MYSQL_USER="root", MYSQL_USER and MYSQL_PASSWORD are for configuring a regular user and cannot be used for the root user
db_mysql | Remove MYSQL_USER="root" and use one of the following to control the root user password:
db_mysql | - MYSQL_ROOT_PASSWORD
db_mysql | - MYSQL_ALLOW_EMPTY_PASSWORD
db_mysql | - MYSQL_RANDOM_ROOT_PASSWORD
web_api | 2021/11/08 13:20:31 dial tcp 127.0.0.1:3306: connect: connection refused
db_mysql exited with code 1
web_api exited with code 1

Answer 1

You should change the db configuration in your app to connect to webapi-mysql instead of 127.0.0.1. Every container gets its own unique address. Docker will create a fake DNS record for webapi-mysql that points to the correct IP address at that time.