Converting Docker-Compose files to Nix

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1

I’m looking for an easy or automatic way to convert a docker-compose.yml file for usage in my server’s configuration.nix. I tried to translate the docker-compose file of invidious, but I fail at translating the environment variables. Is there a way to convert a docker-compose description into a declarative container config? Or can somebody maybe help me out with translating this file?

2

I’m not aware of any way of doing so automatically and that’s probably not something you’d want anyways.
I guess you could convert the YAML to JSON or TOML and then use the appropriate from function to get a Nix attrset which you could turn into an oci container options set with some recursive mapAttrs and filterAttrs but that sounds hairy.

As for environment variables, you need this option: NixOS Search

The | in YAML functions similar to our ''; INVIDIOUS_CONFIG is just a literal string of YAML, declared inside docker-compose’s YAML.

In Nix it’d be:

 virtualisation.oci-containers.containers.<name>.environment = {
  INVIDIOUS_CONFIG = ''
    channel_threads: 1
    check_tables: true
    feed_threads: 1
    db:
      user: kemal
      password: kemal
      host: postgres
      port: 5432
      dbname: invidious
    full_refresh: false
    https_only: false
    domain:
  '';
}

If you want to get real fancy, you could even use lib.generators.toYAML to generate the config YAML from Nix attrsets:

virtualisation.oci-containers.containers.<name>.environment = {
  INVIDIOUS_CONFIG = lib.generators.toYAML {
    channel_threads = 1;
    check_tables = true;
    feed_threads = 1;
    db = {
      user = "kemal";
      password = "kemal":
      host = "postgres";
      port = 5432;
      dbname = "invidious";
    };
    full_refresh = false;
    https_only = false;
    domain = "";
  };
}

Welcome to Nix :wink:

(Note: None of the examples are tested; they may contain translation and/or syntax errors)

1 Like
3

Well, that solves my main problem. Thank you very much.