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@urigoren
Created May 1, 2021 19:41
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A simple cascading config reader
import os, sys, json
from pathlib import Path
class ConfigReader:
def __init__(self, default=None, **kwargs):
self.default=default
self.py_file = Path(os.path.join(os.getcwd(), sys.argv[0])).absolute()
p = self.py_file.parent
found_config_json = []
while p!=Path('/'):
if (p/"config.json").exists():
found_config_json.append(p/"config.json")
p=p.parent
found_config_json = reversed(found_config_json)
self.config_json = dict()
for cfile in found_config_json:
with cfile.open('r') as f:
new_config = json.load(f)
assert type(new_config)==dict
self.config_jdon=dict(self.config_json, **new_config)
self.config_args = dict()
key = None
for arg in sys.argv:
if arg.startswith("-"):
key=arg.strip("-")
elif key is not None:
self.config_args[key]=arg
key = None
self.config_hard_coded = kwargs
def __getitem__(self, key):
# Look for keys in this order:
# (1) key-word arguments for the reader
# (2) Command line argument
# (3) config.json files (in this folder or above - recursively)
# (4) Environment variables
return self.config_hard_coded.get(key, self.config_args.get(key, self.config_json.get(key, os.environ.get(key, self.default))))
config = ConfigReader()
from config_reader import config
print (config["some_value"])
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