python-repositories/python_repositories/adapters/__init__.py

"""
Adapters for various backend repositories (e.g., Redis, Minio).

This module exposes concrete implementations for repository interfaces.
"""

from __future__ import annotations

import importlib
from typing import TYPE_CHECKING

# Adapters are imported only for static type checkers; runtime loading is deferred below.
if TYPE_CHECKING:
    from .file_backed_queue_adapter import FileBackedQueueAdapter
    from .memory_queue_adapter import MemoryQueueAdapter
    from .minio_adapter import MinioAdapter
    from .postgres_adapter import PostgresAdapter
    from .redis_adapter import RedisAdapter

# Map public adapter names to their defining module and class.
# Each adapter module fails fast with an install hint if its extra is missing.
# When adding a new adapter, update this dict and __all__ only.
_LAZY_EXPORTS = {
    "RedisAdapter": (".redis_adapter", "RedisAdapter"),
    "MinioAdapter": (".minio_adapter", "MinioAdapter"),
    "PostgresAdapter": (".postgres_adapter", "PostgresAdapter"),
    "MemoryQueueAdapter": (".memory_queue_adapter", "MemoryQueueAdapter"),
    "FileBackedQueueAdapter": (
        ".file_backed_queue_adapter",
        "FileBackedQueueAdapter",
    ),
}

__all__ = [
    "RedisAdapter",
    "MinioAdapter",
    "PostgresAdapter",
    "MemoryQueueAdapter",
    "FileBackedQueueAdapter",
]


def __getattr__(name: str) -> object:
    """Load an adapter on first access so the base package installs without backend clients."""
    if name in _LAZY_EXPORTS:
        module_path, attr = _LAZY_EXPORTS[name]
        module = importlib.import_module(module_path, __package__)
        return getattr(module, attr)
    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")


def __dir__() -> list[str]:
    """Expose lazy adapter names in tab completion and dir()."""
    return sorted(__all__)