one-config 0.1.0

A universally accessible config object that only has to be constructed once

Config Object

Use

Create a .yaml file in an appropriate place and add some parameters:

# my_config.yaml
my:
  nested:
    - param1
    - param2

Then, at the entry-point(s) of your python package, initialize the CONFIG object with the path to the .yaml file:

# run.py
from config import CONFIG
CONFIG.construct_config('path/to/my_config.yaml')

In any other module, you can import the CONFIG object and the parameters from the yaml file will be present.

# my_module.py
from config import CONFIG
param1 = CONFIG.my.nested.param1

Notice how the nested parameters are accessed as nested attributes.

Motivation

It's common for ML projects to use a large configuration object with all parameters in one place. There are two broad requirements of a configuration object:

1. It should be able to easily represent the parameters of different runtime situations, such as testing and production.
2. It should be available for all modules

In order to achieve the first requirement, the object should be somehow constructed (and done so only once in the codebase).

In order to achieve the second requirement, we could have a config.py file with all configuration parameters as attributes. This could be imported into other modules and used ad hoc.

However, in order to achieve both requirements, we would seemingly have to construct the config object once and inject the constructed config into all other objects in the codebase. This clutters the codebase.

The CONFIG object in this module attempts to resolve this problem by using the (much ridiculed) singleton pattern.

The CONFIG object is constructed once and only once by a method parametrized with the path to a yaml file. Once constructed, the object will contain all parameters even if imported by another module.

Although the code in config.py may be opaque to many readers (and others might disagree about how "pythonic" it is), its implementation should be straightforward and it should be very useful for maintaining clean code in any project.