magnet

magnet

A library that makes it easy to load YAML config files in a hierarchical manner. Also loads YAML content from CONFIG environment variable.

Minimal Python version is Python 3.5.

Installation

pip install magnet

Usage

Consider the following yaml file config/default.yml:

app:
  url: https://www.example.com/app
  certs:
    pem: /path/to/cert.pem
    key: /path/to/cert.key
  clients:
    - a
    - b

And the following config/local.yml file:

app:
  url: https://app.example.com/

from magnet import Config

config = Config().read_all()

config['app.url']           # ==> "https://app.example.com"
config['app.certs.pem']     # ==> "/path/to/cert.pem"
config['non.existing.key']  # ==> raises KeyError

Additional options:

from magnet import Config

# Listed below are the default parameters 
config = Config(
    config={
        # set default configuration here
    },
    filenames=(
       'config/default.yml',
       'config/local.yml',
    ),
    env_variable='CONFIG',
    separator='.',
)

config.read_all(
  filename=None,  # string, can be set to load an additional file
)

This will load the configuration in the following order:

• ./config/default.yml - can be committed to the repository
• ./config/local.yml - should not be committed to allow custom config for devs
• An additional YAML config file (if filename argument is defined)
• YAML contents from the CONFIG environment variable (if env_variable is defined)

All of these files are optional, but the key lookups will result with KeyError if a key is missing. If filename is defined, but the file is not found, it will raise a FileNotFoundError.

Development

make ci            - Run the CI pipeline (deps, lint, test-coverage)
make lint          - Lint all project files
make test          - Run all tests
make test-watch    - Run all tests and re-run on file changes
make test-coverage - Run all tests and calculate test coverage
make deps          - Create a virtual environment and install dependencies
make freeze        - Freeze the requirements
make env           - Create a virtual environment