zirconium 0.1.0

Excellent configuration management for Python

Zirconium

Zirconium is a powerful configuration tool for loading and using configuration in your application.

Key Features

• Out-of-the-box support for:
  • Database tables (with SQLAlchemy installed)
  • YAML (with pyyaml installed)
  • TOML (with toml installed)
  • JSON
  • Setuptools-like CFG files
  • INI files (following the defaults of the configparser module)
  • Environment variables
• Automatic replacement of ${ENVIRONMENT_VARIABLES} in strings
• Consistent type coercion for common data types: paths, ints, floats, decimals, dates, and datetimes
• Where dictionary-style declarations are not supported, instead use the dot syntax (e.g. "foo.bar")
• Supports multiple file encodings
• Extensible to other formats as needed
• Configuration is dict-like for ease-of-use in existing locations (e.g. Flask)
• Multiple files can be specified with different weights to control loading order
• Supports default vs. normal configuration file (defaults always loaded first)
• Supports thread-safe injection of the configuration into your application via autoinject

Example Usage

config = zirconium.ApplicationConfig()

# Direct load configuration from dict:
config.load_from_dict({
    "version": "0.0.1",
    "database": {
        # Load these from environment variables
        "username": "${MYAPP_DATABASE_USERNAME}",
        "password": "${MYAPP_DATABASE_PASSWORD}",
    },
    "escaped_environment_example": "$${NOT_AN_ENVIRONMENT VARIABLE",
    "preceding_dollar_sign": "$$${STOCK_PRICE_ENV_VARIABLE}",
})

# Default configuration, relative to this file, will override the above dict
base_file = pathlib.Path(__file__).parent / ".myapp.defaults.toml"
config.register_default_file(base_file) 

# File in user home directory, overrides the defaults
config.register_file("~/.myapp.toml")

# File in CWD, will override whatever is in home
config.register_file("./.myapp.toml")

# Load a file path from environment variable, will override ALL registered files
config.register_file_from_environ("MYAPP_CONFIG_FILE")

# Load values direct from the environment, will override ALL files including those specific in environment variables
# sets config["database"]["password"]
config.register_environ_var("MYAPP_DATABASE_PASSWORD", "database", "password")
# sets config["database"]["username"]
config.register_environ_var("MYAPP_DATABASE_USERNAME", "database", "username")

# Actually load the configuration file (executes the loads from register_* statements)
config.init()


# Injection example
class NeedsConfiguration:

    config: zirconium.ApplicationConfig = None

    @autoinjector.construct
    def __init__(self):
        # you have self.config available as of here
        pass