### Description I need to start MySQL with `--character-set-server=utf8mb4 --collation-server=utf8mb4_unicode_ci` options. The docker image supports `my.cnf` options: ``` docker run --name some-mysql -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql:tag --character-set-server=utf8mb4 --collation-server=utf8mb4_unicode_ci ``` I didn't find any documentation on command line arguments for services, so I'm deducing that passing arguments to services is not supported at this time. Is there any way to pass `my.cnf` options, except building a custom image, in `gitlab-ci.yml` ? ### Proposal We have the [command](https://docs.docker.com/compose/compose-file/#command) option in `docker-compose` for this purpose. It would be nice to add a similar option under `services` for `gitlab-ci.yml`. ### Links / references * _Commandline arguments in docker-compose_ - StackOveflow, [link](http://stackoverflow.com/questions/36640750/commandline-arguments-in-docker-compose) * _Docker compose file reference_ - docker.com, [link](https://docs.docker.com/compose/compose-file/) * _MySQL docker hub_ - docker.com, [link](https://hub.docker.com/_/mysql/)