hojichar.utils.load_compose

  1from __future__ import annotations
  2
  3import importlib.util
  4import logging
  5import sys
  6from os import PathLike
  7from pathlib import Path
  8from types import ModuleType
  9from typing import Any, Callable, Optional, Union
 10
 11import hojichar
 12
 13logger = logging.getLogger(__name__)
 14
 15
 16def _load_module(path: Union[str, PathLike]) -> ModuleType:
 17    # HACK type hint `os.PathLike[str]` is not allowed in Python 3.8 or older.
 18    # So I write Union[str, PathLike]
 19    path_obj = Path(path)
 20    module_name = path_obj.stem
 21    spec = importlib.util.spec_from_file_location(module_name, path_obj)
 22    if spec and spec.loader:
 23        module = importlib.util.module_from_spec(spec)
 24        sys.modules[module_name] = module
 25        spec.loader.exec_module(module)
 26    return module
 27
 28
 29def load_filter_from_file(
 30    profile_path: Union[str, PathLike],
 31) -> hojichar.Compose | hojichar.AsyncCompose:
 32    """
 33    Loading a profile which has `FILTER` variable.
 34    Given path is added to sys.path automaticaly.
 35
 36    Args:
 37        profile_path (str): Path to a Python file that implements custom filter
 38        hojichar.Compose must be defined as FILTER variable in the file.
 39
 40    Raises:
 41        NotImplementedError:
 42
 43    Returns:
 44        hojichar.Compose | hojichar.AsyncCompose:
 45    """
 46    sys.path.append(str(Path(profile_path).parent))
 47    module = _load_module(profile_path)
 48    if hasattr(module, "FILTER"):
 49        filter = getattr(module, "FILTER")
 50        if not isinstance(filter, (hojichar.Compose, hojichar.AsyncCompose)):
 51            raise TypeError("FILTER must be Compose or AsyncCompose object.")
 52        return filter
 53    else:
 54        raise NotImplementedError("FILTER is not defined in the profile.")
 55
 56
 57def load_factory_from_file(
 58    profile_path: Union[str, PathLike],
 59) -> Callable[[Optional[Any]], hojichar.Compose | hojichar.AsyncCompose]:
 60    """
 61    Loading a function by a profile which has `FACTORY` variable.
 62    Given path is added to sys.path automaticaly.
 63
 64    Args:
 65        profile_path (PathLike): Path to a Python file that implements custom filter
 66
 67    Raises:
 68        NotImplementedError:
 69
 70    Returns:
 71        Callable[[Optional[Any]], hojichar.Compose | hojichar.AsyncCompose]:
 72            An alias of the function which returns Compose or AsyncCompose.
 73    """
 74    sys.path.append(str(Path(profile_path).parent))
 75    module = _load_module(profile_path)
 76    if hasattr(module, "FACTORY"):
 77        factory: Callable[[Optional[Any]], hojichar.Compose | hojichar.AsyncCompose] = getattr(
 78            module, "FACTORY"
 79        )
 80        return factory
 81    else:
 82        raise NotImplementedError("FACTORY is not defined in the profile")
 83
 84
 85def load_parametrized_filter_from_file(
 86    profile_path: Union[str, PathLike], *factory_args: str
 87) -> hojichar.Compose | hojichar.AsyncCompose:
 88    factory = load_factory_from_file(profile_path)
 89    filter = factory(*factory_args)
 90    return filter
 91
 92
 93def load_compose(
 94    profile_path: Union[str, PathLike], *factory_args: str
 95) -> hojichar.Compose | hojichar.AsyncCompose:
 96    """
 97    Loading a Compose file from profile. Loading a Compose file from the profile.
 98    Both `FILTER` and `FACTORY` pattern of the profile is loaded.
 99
100    Args:
101        profile_path (PathLike):
102
103    Returns:
104        hojichar.Compose:
105    """
106    try:
107        filter = load_filter_from_file(profile_path)
108        _check_args_num_mismatch(len(factory_args))
109        return filter
110    except NotImplementedError:
111        return load_parametrized_filter_from_file(profile_path, *factory_args)
112
113
114def _check_args_num_mismatch(num_args: int) -> None:
115    if num_args > 0:
116        logger.warning(f"Warning: {num_args} arguments are ignored.")