PKonfig Concepts and Glossary

• Config

  • Base class you subclass to declare configuration. Contains field descriptors and optional nested Configs.

• Field

  • Descriptor that defines type, default, and validation. Examples: Str, Int, Bool, Choice, ListField, LogLevel.

• Storage

  • Source of values. Implementations flatten keys into tuples, e.g., ("db", "host"). Built-ins: Env, DotEnv, Yaml, Json, Toml, Ini, plus DictStorage for in-memory values.

• Precedence

  • Storages are checked left-to-right. The first storage holding a key wins.

• Aliases

  • Namespaces for nested Configs so you can have APP_DB_HOST map to cfg.db.host.

• Validation

  • Fields cast and validate values. Missing required values or failed casts raise clear exceptions.

• Fail-fast

  • By default, PKonfig validates at construction (fail_fast=True). Set fail_fast=False to defer, and call cfg.check() later.

• Type annotations

  • PKonfig embraces Python type hints for clean, dev-friendly configs. Always annotate your fields (e.g., host: str). Field descriptors still provide runtime casting/validation.

• Example putting it together

  from pkonfig.config import Config
  from pkonfig import storage
  
  class DB(Config):
      host: str
      port: int
  
  class App(Config):
      debug = False
      db: DB
  
  cfg = App(storage.Env(prefix="APP"))
  

• See also

  • Quickstart for minimal setup

  • Tutorials for deep dives

  • API for full reference