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Abstract Inverter Factory API

sweet_tea.abstract_inverter_factory.AbstractInverterFactory

class AbstractInverterFactory(Generic[T], InverterFactory):

A generic inverter factory that constrains class retrieval to subclasses of type T.

This factory combines the type constraints of AbstractFactory with the class-definition-returning behavior of InverterFactory. It allows retrieval of class definitions that are subclasses of a specified generic type, enabling type-safe factory patterns for lazy construction scenarios.

Usage: 

factory = AbstractInverterFactory[MyBaseClass]
class_def = factory.create('my_key')
# Only classes inheriting from MyBaseClass will be available
instance = class_def(**kwargs)  # Instantiate when ready

create(key, library='', label='') classmethod

Retrieve the class definition for a registered class that is a subclass of the generic type.

Parameters:

  • key (str): Name to reference the class from the registry.
  • library (str, default ''): Optional library filter for the class.
  • label (str, default ''): Optional label filter for the class.

Returns: Type[Any] - The class definition that can be instantiated by the caller.

Raises: SweetTeaError - When the key is not found or filters don't match.

Example: 

from sweet_tea import AbstractInverterFactory, Registry

class Service:
    def __init__(self, config=None):
        self.config = config

class DatabaseService(Service):
    pass

Registry.register("database", DatabaseService)

# Get class definition with type constraints
factory = AbstractInverterFactory[Service]
db_class = factory.create("database")

# Instantiate later
db = db_class(config={"host": "localhost"})

_get_generic_type() classmethod

Get the generic type parameter.

Returns: Type[T] - The generic type parameter.

__class_getitem__(item) classmethod

Create a parameterized generic subclass with the specified type.

Parameters:

  • item (Type[T]): The base class type to constrain to.

Returns: Type[AbstractInverterFactory[T]] - A parameterized factory class.