Coverage for src/configuraptor/loaders/register.py: 100%
27 statements
« prev ^ index » next coverage.py v7.2.7, created at 2023-07-21 10:19 +0200
« prev ^ index » next coverage.py v7.2.7, created at 2023-07-21 10:19 +0200
1"""
2Exposes `register_loader` to define loader for specific file types.
3"""
5import typing
6from pathlib import Path
8from ._types import T_config
10T_loader = typing.Callable[[typing.BinaryIO, Path], T_config]
11T_WrappedLoader = typing.Callable[[T_loader], T_loader]
13LOADERS: dict[str, T_loader] = {}
16@typing.overload
17def register_loader(*extension_args: str) -> T_WrappedLoader:
18 """
19 Overload for case with parens.
21 @register_loader("yaml", ".yml")
22 def load_yaml(...):
23 ...
25 # extension_args is a tuple of strings
26 # this will return a wrapper which takes `load_yaml` as input and output.
27 """
30@typing.overload
31def register_loader(*extension_args: T_loader) -> T_loader:
32 """
33 Overload for case without parens.
35 @register_loader
36 def json(...):
37 ...
39 # extension_args is a tuple of 1: `def json`
40 # this will simply return the `json` method itself.
41 """
44def register_loader(*extension_args: str | T_loader) -> T_loader | T_WrappedLoader:
45 """
46 Register a data loader for a new filetype.
48 Used as a decorator on a method that takes two arguments:
49 (BinaryIO, Path) - an open binary file stream to the config file and the pathlib.Path to the config file.
50 By default, the open file handler can be used.
51 However, some loaders (such as .ini) don't support binary file streams.
52 These can use the Path to open and read the file themselves however they please.
53 """
54 f_outer = None
55 extension_set = set()
57 for extension in extension_args:
58 if not isinstance(extension, str):
59 f_outer = extension
60 extension = extension.__name__
62 elif extension.startswith("."):
63 extension = extension.removeprefix(".")
65 extension_set.add(extension)
67 def wrapper(f_inner: T_loader) -> T_loader:
68 LOADERS.update({ext: f_inner for ext in extension_set})
69 return f_inner
71 if f_outer:
72 return wrapper(f_outer) # -> T_Loader
73 else:
74 return wrapper # -> T_WrappedLoader
77__all__ = ["register_loader", "LOADERS"]