lco's Introduction

Light Config (lco)

Load a config file once and use it as you would use enviroment variables from anywhere in your code.

Somewhere:

import lco

lco.init("some_config.yml")

You can also set the enviroment variable LCO_CONFIG instead.

Somewhere else entirely, 10 layers deep in some object.

import lco

lco["some_value"]
lco["some_group"]["some_value"]

This works across threads and processes.

Installation

You can use pip install lco.

But this is such a small package, it might be best to just copy the code below into your own lco.py.

Show Code

import os
import sys
import yaml

class LCO(object):
  def __init__(self):
    global _lco_obj
    if "_lco_obj" not in globals():
      if "LCO_CONFIG" in os.environ:
        config = os.environ["LCO_CONFIG"]
        if os.path.exists(config):
          with open(config, "r") as f:
            _lco_obj = yaml.safe_load(f)
        else:
          raise ValueError("LCO_CONFIG is not a file: %s" % config)

  def init(self, config):
    global _lco_obj
    if "_lco_obj" not in globals():
      with open(config, "r") as f:
        _lco_obj = yaml.safe_load(f)
      os.environ["LCO_CONFIG"] = config

  def __getitem__(self, name):
    global _lco_obj
    if name not in _lco_obj:
      raise KeyError("No such key: %s" % name)
    return _lco_obj[name]

sys.modules["lco"] = LCO()

But why?

This is mostly useful for research code, MVPs or Prototypes, where one doesn't want to pass configuration variables from object to object or across scopes. I wouldn't recommend this for production code as you're essentially using global variables.