compose.db-proxy.yml

services:
    db:
        image: ubuntu:22.04
        volumes:
            - "${SSH_AUTH_SOCK:?SSH configuration is incomplete}:/ssh-agent"
        environment:
            SSH_AUTH_SOCK: '/ssh-agent'
            PROXY_SSH_SERVER: '${PROXY_SSH_SERVER:?SSH configuration is incomplete}'
            PROXY_SSH_USER: '${PROXY_SSH_USER:?SSH configuration is incomplete}'
            REMOTE_MYSQL_HOST: ${REMOTE_MYSQL_HOST:?Database configuration seems to be missing}
            REMOTE_MYSQL_PORT: ${REMOTE_MYSQL_PORT:?Database configuration seems to be missing}
        expose:
            - '3306'
        # ssh -o ExitOnForwardFailure=yes -f -N -L 0.0.0.0:3306:$$REMOTE_MYSQL_HOST:$$REMOTE_MYSQL_HOST $$PROXY_SSH_USER@$$PROXY_SSH_SERVER
        command:
            - bash
            - -c
            - >-
                apt-get update -y && apt-get install -y openssh-client mysql-client;
                mkdir -p ~/.ssh; chmod 700 ~/.ssh;
                ssh-keygen -R $$PROXY_SSH_SERVER; ssh-keyscan -H $$PROXY_SSH_SERVER >> ~/.ssh/known_hosts;
                ssh -o ExitOnForwardFailure=yes -N -L 0.0.0.0:3306:$$REMOTE_MYSQL_HOST:$$REMOTE_MYSQL_PORT $$PROXY_SSH_USER@$$PROXY_SSH_SERVER