Parse configuration values from files, the environment, and elsewhere all in one place.
Here is a full working example of using easy_config. First, write your configuration class:
# config.py
from easy_config import EasyConfig
class MyProgramConfig(EasyConfig):
FILES = ['myprogram.ini']
NAME = 'MyProgram' # the name for the .ini file section and the namespace prefix for environment variables
# define the options like you would a dataclass
number: int
name: str
check_bounds: bool = True # options with defaults must all come after non-default options
A sample configuration file:
# myprogram.ini
[MyProgram]
# section name matches `NAME` from the configuration class
number = 3
And a sample program to illustrate the usage:
# test_config.py
import sys
from config import MyProgramConfig
print(MyProgramConfig.load(name=sys.argv[1])
Running this program with various options:
$ python test_config.py Scott
MyProgramConfig(number=3, name='Scott', check_bounds=True)
$ env MYPROGRAM_CHECK_BOUNDS=False python test_config.py Scott
# environment variable names are the all-uppercase transformation of the NAME concatenated with the option name and an underscore
MyProgramConfig(number=3, name='Scott', check_bounds=False)
$ env MYPROGRAM_NUMBER=10 MYPROGRAM_NAME=Charlie python test_config.py Scott
MyProgramConfig(number=10, name='Scott', check_bounds=True)
As you can see, values are taken in precedence, with arguments passed to load
overriding values from the environment which, in turn, override values from
configuration files.
Once you have the MyProgramConfig
instance, you can use it just like any dataclass.