configen

Automatically generates Structured Configs that can be used with hydra.utils.instantiate()

This is optional at two levels:

1. Structured Configs are optional, one can use Hydra without them.
2. One can manually code these dataclasses. The advantage of this tool is that it does the work automatically.

Setup

Configen requires config file per project. The config indicates what classes to generate code for, where to put the generated code etc. Configen will suggest creating a config on the first run:

$ configen 
[2020-08-14 12:06:11,359][configen.configen][ERROR] - Use --config-dir DIR.
If you have no config dir yet use the following command to create an initial config in the `conf` dir:
        configen init_config_dir=conf
$ configen init_config_dir=conf
[2020-08-14 12:07:07,752][configen.configen][INFO] - Initializing config in 'conf'

This will generate a basic config similar to:

$ cat conf/configen.yaml 
configen:
  # output directory
  output_dir: ${hydra:runtime.cwd}/gen

  header: |
    # Generated by configen, do not edit.
    # See https://github.com/facebookresearch/hydra/tree/master/tools/configen

  # The directory of each module under output_dir
  module_dir: '{{module_path}}/conf'

  # list of modules to generate configs for
  modules:
    - name: configen.samples.user
      # for each module, a list of classes
      classes:
        - User

Configen comes with a few samples classes that are being processed by the default config. For example:

class User:
    def __init__(self, age: int, name: str):
        self.age = age
        self.name = name

Running configen with this config directory:

$ configen --config-dir conf
[2020-08-14 12:44:54,990][configen.configen][INFO] - configen.samples.user.User -> /home/omry/tmp/configen/gen/configen/samples/user/conf/User.py

Will result in a file gen/configen/samples/user/conf/User.py like:

# Generated by configen, do not edit.
# See https://github.com/facebookresearch/hydra/tree/master/tools/configen
# fmt: off
# isort:skip_file
# flake8: noqa

from dataclasses import dataclass
from typing import *

from omegaconf import MISSING


@dataclass
class UserConf:
    _target_: str = "configen.samples.user.User"
    age: int = MISSING
    name: str = MISSING

The generated code can be used by a Hydra application to instantiate the user object. See the example aplication.