Create multiple buckets during docker compose setup

I want to create multiple buckets using a docker compose but I could not find any resource to accomplish this task. I’ve managed to create a single bucket, a new user with initial credentials and a new organization using a docker compose file. In version 1.x it was possible to use the influxd command to provide a configuration file but it seems that there is no equivalent command in version 2.x. I’ve also tried to use the setup command but that did only work for the initial values not a second bucket.
I’ve attached my docker-compose and the which worked for one initial bucket.