cliconfig 0.4.2

Merge your config files and set parameters from the command line in a simple way.

CLI Config

Lightweight library that provides routines to merge your configs (optionally nested) and set parameters from command line. It is also provide processing functions that can change the whole config before and after each config merge, before config saving and after config loading. It also contains many routines to manipulate the config as flatten or nested dicts.

Documentation :memo: here

Installation

In a new virtual environment, simply install the package with:

pip install cliconfig

This package is OS independent and supported on Linux, macOS and Windows.

Quick start

First create a default config that can be split in multiple files that will be merged (from left to right in make_config function). There is no limit of depth for the configuration parameters.

---  # default1.yaml
param1: 1
param2: 0
letters:
  letter1: a
  letter2: b

---  # default2.yaml
param1: 1
param2: 2  # will override param2 from default1.yaml
letters.letter3: c  # add a new parameter

Now you can set up your program to use the config:

# main.py
from cliconfig import make_config, show_config

config, _ = make_config('default1.yaml', 'default2.yaml')
show_config(config)

Then add one or multiple additional config files that will be passed on command line and that will override the default values.

---  # first.yaml
letters:
  letter3: C

---  # second.yaml
param1: -1
letters.letter1: A

Be careful, The additional config files cannot add new parameters that are not in default configs. It is intended to prevent typos in the config files that would not be detected. It also improves the readability of the config files and the retro-compatibility.

Now you can launch the program with additional configurations and parameters. The additional configuration paths are indicated with --config followed by a whitespace. If there are several paths, they should be separate with comma, without space. Then, you can set individual parameters with --<subconfig.param_name> (use dot for nested configs).

The default configuration will be merged to the default configs with the additional configurations (from left to right), then the parameters will be set. For example:

python main.py --config first.yaml,second.yaml --param2=-2 --letters.letter2='B'

Will show:

[CONFIG] Merge 2 default configs, 2 additional configs and 2 CLI parameter(s).

Config:
    param1: -1
    param2: -2
    letters:
        letter1: A
        letter2: B
        letter3: C

Note that the configurations are native python dicts at each step of the process.

Use tags

By default, the package provides some "tags" that are strings starting with @ and placed at the end of a key containing a parameter. It will change the way the configuration is processed.

The default tags are:

• @merge_add, @merge_before and @merge_after to merge the dict loaded from the value (should be a yaml path!) to the current configuration. @merge_add allow only new keys and is useful to split sub-configurations in multiple files. @merge_before will merge the current dict on the loaded one and @merge_after will merge the loaded dict on the current one. With theses tags, you can dynamically merge configurations depending on the paths you set as values.
• @copy Copy a parameter from another key. The value should be a string containing this flatten key
• @type:<my type> To check if the key is of the type <my type> at each update even if the tag is no longer present. It supports basic type (except tuple and sets that are not handled by yaml) as well as union (with "Union" or "|"), optional, lists and dicts.

The tags are applied in this order: @merge, @copy then @type.

Note that the tags are only used to trigger internal processing and will be automatically removed from the key after the processing.

You can also combine the tags, example:

---  # main.yaml
path_1@merge_add: sub1.yaml
path_2@merge_add: sub2.yaml
--- # sub1.yaml
config1:
  param@copy@type:int: config1.param2
  param2@type:int: 1
--- # sub2.yaml
config2.param@type:None|int: 2

Here main.yaml is interpreted like:

path_1: sub1.yaml
path_2: sub2.yaml
config1:
    param: 1
    param2: 1
config2:
    param: 2

and now, all the parameters have a forced type.

The point is that you can easily create your own processing associated to your own tags. They provide a large number of possibilities to customize the configuration process and are describe in the Processing section of the documentation.

Edge cases

Be careful, tuples and sets are not supported by YAML and cannot be used in yaml files. Use lists instead if possible.

None is not recognized as a None object by YAML but as a string, you may use null or Null instead if you want to set a None object.

Dicts are considered as sub-configs and so you may not be able to change the keys in the additional configs. If you want to modify or add dict keys, you should enclose it in a list.

For instance:

--- default.yaml
logging:
  metrics: ['train loss', 'val loss']
  styles: [{'train loss': 'red', 'val loss': 'blue'}]
--- experiment.yaml
logging:
  metrics: ['train loss', 'val loss', 'val acc']
  styles: [{'train loss': 'red', 'val loss': 'blue', 'val acc': 'cyan'}]

How to contribute

For development, install the package dynamically and dev requirements with:

pip install -e .
pip install -r requirements-dev.txt

Everyone can contribute to CLI Config, and we value everyone’s contributions. Please see our contributing guidelines for more information 🤗

Todo

Priority:

• allow passing new arguments by CLI (with warning and no actual merge)
• add a routine to check if a tag is in a key and robust to all other possible tags
• add an integration test with all built-in processing (and more)

Secondary:

• add make_processing_keep_status to make a processing that keep the status of a parameter across merged configs. The status is any python object returned by a function that takes the parameter as input
• add ProcessSelect (with tag "@select") to select a subconfig (or parameter) and delete the others configs at the same level (to cure the resulting config)
• allow nested types in ProcessTyping
• add DefaultProcessing that add default processing to list of processing

License

Copyright (C) 2023 Valentin Goldité

This program is free software: you can redistribute it and/or modify it under the terms of the MIT License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

This project is free to use for COMMERCIAL USE, MODIFICATION, DISTRIBUTION and PRIVATE USE as long as the original license is include as well as this copy right notice at the top of the modified files.